grepcent / static financial knowledge base

NorthWestern Energy Group, Inc. (NWE)

CIK: 0001993004. SIC: 4931 Electric & Other Services Combined. Latest 10-K as of: 2026-02-12.

SIC breadcrumb: Transportation, Communications, Electric, Gas, And Sanitary Services > Electric, Gas, And Sanitary Services > SIC 4931 Electric & Other Services Combined

SEC company page: https://www.sec.gov/edgar/browse/?CIK=1993004. Latest filing source: 0001993004-26-000006.

Informational only - descriptive public-record data, not investment advice.

Business

Read NWE's verbatim Item 1 Business section from its latest 10-K: Business.

Risk Factors

Read NWE's verbatim Item 1A Risk Factors from its latest 10-K: Risk Factors.

Selected Fundamentals

MetricValueUnitFYFiled
Revenue1,610,559,000USD20252026-02-12
Net income181,092,000USD20252026-02-12
Assets8,459,691,000USD20252026-02-12

Financials

Annual standardized facts from SEC companyfacts as of latest extracted filing date 2026-02-12. Source: https://data.sec.gov/api/xbrl/companyfacts/CIK0001993004.json. Derived margins, ratios, and free cash flow are computed from the extracted annual SEC facts.

Download these verified figures (annual + quarterly, with per-value filing provenance): JSON · CSV

Flow metrics use full-year FY periods from 10-K/10-K/A filings; balance-sheet metrics use FY-end instants. Free cash flow = operating cash flow - capital expenditures. Missing metrics are omitted rather than fabricated.

Metric202020212022202320242025
Revenue1,372,316,0001,477,837,0001,422,143,0001,513,898,0001,610,559,000
Net income186,840,000183,008,000194,131,000224,111,000181,092,000
Operating income275,681,000263,079,000300,455,000323,321,000325,818,000
Diluted EPS3.603.253.223.652.94
Operating cash flow219,978,000307,242,000489,231,000406,741,000394,455,000
Capital expenditures434,328,000515,140,000566,889,000549,244,000524,456,000
Dividends paid128,483,000140,062,000154,050,000158,589,000161,389,000
Assets6,780,443,0007,317,783,0007,600,652,0007,997,524,0008,459,691,000
Liabilities4,652,600,0004,815,338,0005,139,824,0005,573,951,000
Stockholders' equity2,079,095,0002,339,713,0002,665,183,0002,785,314,0002,857,700,0002,885,740,000
Cash and cash equivalents2,820,0008,489,0009,164,0004,283,0008,781,000
Free cash flow-214,350,000-207,898,000-77,658,000-142,503,000-130,001,000

Ratios

ROE and ROA use period-end equity/assets. Liabilities / equity uses total liabilities divided by stockholders' equity. Current ratio uses current assets divided by current liabilities when both are reported.

Metric202020212022202320242025
Net margin13.61%12.38%13.65%14.80%11.24%
Operating margin20.09%17.80%21.13%21.36%20.23%
Return on equity7.99%6.87%6.97%7.84%6.28%
Return on assets2.76%2.50%2.55%2.80%2.14%
Liabilities / equity1.751.731.801.93
Current ratio0.870.760.520.72

Industry Peer Context

Each number-line places NWE against the min, median, and max of latest reported values among companies in the same SIC industry when at least three peers report that ratio.

Net margin peer context

NWE Net margin versus SIC peer range. Source: grepcent computed from latest SEC companyfacts ratios for SIC industry 4931; peer count 16.NWE Net margin versus SIC peer range. Source: grepcent computed from latest SEC companyfacts ratios for SIC industry 4931; peer count 16.16 SIC peersMin 4.8%Median 13.1%Max 18.6%NWE 11.2%

Operating margin peer context

NWE Operating margin versus SIC peer range. Source: grepcent computed from latest SEC companyfacts ratios for SIC industry 4931; peer count 16.NWE Operating margin versus SIC peer range. Source: grepcent computed from latest SEC companyfacts ratios for SIC industry 4931; peer count 16.16 SIC peersMin 5.5%Median 20.7%Max 27.6%NWE 20.2%

ROE peer context

NWE ROE versus SIC peer range. Source: grepcent computed from latest SEC companyfacts ratios for SIC industry 4931; peer count 16.NWE ROE versus SIC peer range. Source: grepcent computed from latest SEC companyfacts ratios for SIC industry 4931; peer count 16.16 SIC peersMin 6.3%Median 9.6%Max 12.4%NWE 6.3%

ROA peer context

NWE ROA versus SIC peer range. Source: grepcent computed from latest SEC companyfacts ratios for SIC industry 4931; peer count 16.NWE ROA versus SIC peer range. Source: grepcent computed from latest SEC companyfacts ratios for SIC industry 4931; peer count 16.16 SIC peersMin 1.9%Median 2.6%Max 6.2%NWE 2.1%

Financial Bridges

Waterfall figures reconcile reported SEC companyfacts components. Missing bridges are omitted when required components are not present for the same fiscal year.

Free cash flow = operating cash flow - capital expenditures

NWE FY2025 free cash flow bridge from reported figures.NWE FY2025 free cash flow bridge from reported figures.NWE free cash flow bridgeFY2025: operating cash flow less capital expendituresSource: SEC companyfacts FY2025.Free cash flow bridgeReported amount-$250.0M$0.0B$500.0M$394.5MOperating cash flow-$524.5MCapex-$130.0MFree cash flow

Figure provenance: SEC companyfacts FY 2025. Operating cash flow: accession 0001993004-26-000006; concept NetCashProvidedByUsedInOperatingActivities; source concepts us-gaap:NetCashProvidedByUsedInOperatingActivities | Capital expenditures: accession 0001993004-26-000006; concept PaymentsToAcquirePropertyPlantAndEquipment; source concepts us-gaap:PaymentsToAcquirePropertyPlantAndEquipment | Free cash flow: accession 0001993004-26-000006; concept NetCashProvidedByUsedInOperatingActivities - PaymentsToAcquirePropertyPlantAndEquipment; source concepts us-gaap:NetCashProvidedByUsedInOperatingActivities; us-gaap:PaymentsToAcquirePropertyPlantAndEquipment

Financial Charts

NWE revenue, last 5 periods. Source: SEC companyfacts FY2025.NWE revenue, last 5 periods. Source: SEC companyfacts FY2025.NWE RevenueLatest point: FY2025 = $1.6BSource: SEC companyfacts FY2025.Fiscal yearReported revenue$0.0B$1.0B$2.0BFY2021FY2022FY2023FY2024FY2025

Figure provenance: SEC companyfacts. Latest point: FY 2025 ended 2025-12-31; accession 0001993004-26-000006; filed 2026-02-12. Concept: Revenues. Source concepts: us-gaap:Revenues.

NWE net income, last 5 periods. Source: SEC companyfacts FY2025.NWE net income, last 5 periods. Source: SEC companyfacts FY2025.NWE Net incomeLatest point: FY2025 = $181.1MSource: SEC companyfacts FY2025.Fiscal yearNet income$0.0B$125.0M$250.0MFY2021FY2022FY2023FY2024FY2025

Figure provenance: SEC companyfacts. Latest point: FY 2025 ended 2025-12-31; accession 0001993004-26-000006; filed 2026-02-12. Concept: NetIncomeLoss. Source concepts: us-gaap:NetIncomeLoss.

NWE operating income, last 5 periods. Source: SEC companyfacts FY2025.NWE operating income, last 5 periods. Source: SEC companyfacts FY2025.NWE Operating incomeLatest point: FY2025 = $325.8MSource: SEC companyfacts FY2025.Fiscal yearOperating income$0.0B$250.0M$500.0MFY2021FY2022FY2023FY2024FY2025

Figure provenance: SEC companyfacts. Latest point: FY 2025 ended 2025-12-31; accession 0001993004-26-000006; filed 2026-02-12. Concept: OperatingIncomeLoss. Source concepts: us-gaap:OperatingIncomeLoss.

NWE diluted eps, last 5 periods. Source: SEC companyfacts FY2025.NWE diluted eps, last 5 periods. Source: SEC companyfacts FY2025.NWE Diluted EPSLatest point: FY2025 = $2.94/shareSource: SEC companyfacts FY2025.Fiscal yearDiluted EPS (USD/share)$0.00/share$3.00/share$6.00/shareFY2021FY2022FY2023FY2024FY2025

Figure provenance: SEC companyfacts. Latest point: FY 2025 ended 2025-12-31; accession 0001993004-26-000006; filed 2026-02-12. Concept: EarningsPerShareDiluted. Source concepts: us-gaap:EarningsPerShareDiluted.

NWE operating cash flow, last 5 periods. Source: SEC companyfacts FY2025.NWE operating cash flow, last 5 periods. Source: SEC companyfacts FY2025.NWE Operating cash flowLatest point: FY2025 = $394.5MSource: SEC companyfacts FY2025.Fiscal yearOperating cash flow$0.0B$250.0M$500.0MFY2021FY2022FY2023FY2024FY2025

Figure provenance: SEC companyfacts. Latest point: FY 2025 ended 2025-12-31; accession 0001993004-26-000006; filed 2026-02-12. Concept: NetCashProvidedByUsedInOperatingActivities. Source concepts: us-gaap:NetCashProvidedByUsedInOperatingActivities.

NWE capital expenditures, last 5 periods. Source: SEC companyfacts FY2025.NWE capital expenditures, last 5 periods. Source: SEC companyfacts FY2025.NWE Capital expendituresLatest point: FY2025 = $524.5MSource: SEC companyfacts FY2025.Fiscal yearCapital expenditures$0.0B$375.0M$750.0MFY2021FY2022FY2023FY2024FY2025

Figure provenance: SEC companyfacts. Latest point: FY 2025 ended 2025-12-31; accession 0001993004-26-000006; filed 2026-02-12. Concept: PaymentsToAcquirePropertyPlantAndEquipment. Source concepts: us-gaap:PaymentsToAcquirePropertyPlantAndEquipment.

NWE dividends paid, last 5 periods. Source: SEC companyfacts FY2025.NWE dividends paid, last 5 periods. Source: SEC companyfacts FY2025.NWE Dividends paidLatest point: FY2025 = $161.4MSource: SEC companyfacts FY2025.Fiscal yearDividends paid$0.0B$125.0M$250.0MFY2021FY2022FY2023FY2024FY2025

Figure provenance: SEC companyfacts. Latest point: FY 2025 ended 2025-12-31; accession 0001993004-26-000006; filed 2026-02-12. Concept: PaymentsOfDividendsCommonStock. Source concepts: us-gaap:PaymentsOfDividendsCommonStock.

NWE assets, last 5 periods. Source: SEC companyfacts FY2025.NWE assets, last 5 periods. Source: SEC companyfacts FY2025.NWE AssetsLatest point: FY2025 = $8.5BSource: SEC companyfacts FY2025.Fiscal yearAssets$0.0B$5.0B$10.0BFY2021FY2022FY2023FY2024FY2025

Figure provenance: SEC companyfacts. Latest point: FY 2025 ended 2025-12-31; accession 0001993004-26-000006; filed 2026-02-12. Concept: Assets. Source concepts: us-gaap:Assets.

NWE liabilities, last 4 periods. Source: SEC companyfacts FY2025.NWE liabilities, last 4 periods. Source: SEC companyfacts FY2025.NWE LiabilitiesLatest point: FY2025 = $5.6BSource: SEC companyfacts FY2025.Fiscal yearLiabilities$0.0B$3.0B$6.0B$4.7BFY2022$4.8BFY2023$5.1BFY2024$5.6BFY2025

Figure provenance: SEC companyfacts. Latest point: FY 2025 ended 2025-12-31; accession 0001993004-26-000006; filed 2026-02-12. Concept: Liabilities. Source concepts: us-gaap:Liabilities.

NWE stockholders' equity, last 5 periods. Source: SEC companyfacts FY2025.NWE stockholders' equity, last 5 periods. Source: SEC companyfacts FY2025.NWE Stockholders' equityLatest point: FY2025 = $2.9BSource: SEC companyfacts FY2025.Fiscal yearStockholders' equity$0.0B$2.0B$4.0BFY2021FY2022FY2023FY2024FY2025

Figure provenance: SEC companyfacts. Latest point: FY 2025 ended 2025-12-31; accession 0001993004-26-000006; filed 2026-02-12. Concept: StockholdersEquity. Source concepts: us-gaap:StockholdersEquity.

NWE cash and cash equivalents, last 5 periods. Source: SEC companyfacts FY2025.NWE cash and cash equivalents, last 5 periods. Source: SEC companyfacts FY2025.NWE Cash and cash equivalentsLatest point: FY2025 = $8.8MSource: SEC companyfacts FY2025.Fiscal yearCash and cash equivalents$0.0B$125.0M$250.0MFY2021FY2022FY2023FY2024FY2025

Figure provenance: SEC companyfacts. Latest point: FY 2025 ended 2025-12-31; accession 0001993004-26-000006; filed 2026-02-12. Concept: CashAndCashEquivalentsAtCarryingValue. Source concepts: us-gaap:CashAndCashEquivalentsAtCarryingValue.

NWE free cash flow, last 5 periods. Source: SEC companyfacts FY2025.NWE free cash flow, last 5 periods. Source: SEC companyfacts FY2025.NWE Free cash flowLatest point: FY2025 = -$130.0MSource: SEC companyfacts FY2025.Fiscal yearFree cash flow-$250.0M-$125.0M$0.0BFY2021FY2022FY2023FY2024FY2025

Figure provenance: SEC companyfacts. Latest point: FY 2025 ended 2025-12-31; accession 0001993004-26-000006; filed 2026-02-12. Concept: NetCashProvidedByUsedInOperatingActivities - PaymentsToAcquirePropertyPlantAndEquipment. Source concepts: us-gaap:NetCashProvidedByUsedInOperatingActivities; us-gaap:PaymentsToAcquirePropertyPlantAndEquipment.

Quarterly

Quarterly standardized facts from SEC companyfacts as of latest extracted filing date 2026-04-30. Source: https://data.sec.gov/api/xbrl/companyfacts/CIK0001993004.json.

Flow metrics use discrete quarter-length periods from 10-Q/10-Q/A filings. Q4 revenue and net income are derived only when annual FY and nine-month YTD facts exist for the same fiscal year; derived Q4 values are labeled. EPS Q4 is not derived.

QuarterEnd DateRevenueNet IncomeDiluted EPSMethod
2023-Q32023-09-30321,090,00029,335,0000.48reported discrete quarter
2023-Q42023-12-31356,009,00083,142,000derived Q4 = FY annual - nine-month YTD
2024-Q12024-03-31475,342,00065,086,0001.06reported discrete quarter
2024-Q22024-06-30319,929,00031,654,0000.52reported discrete quarter
2024-Q32024-09-30345,161,00046,819,0000.76reported discrete quarter
2024-Q42024-12-31373,466,00080,552,000derived Q4 = FY annual - nine-month YTD
2025-Q12025-03-31466,630,00076,940,0001.25reported discrete quarter
2025-Q22025-06-30342,713,00021,228,0000.35reported discrete quarter
2025-Q32025-09-30386,952,00038,233,0000.62reported discrete quarter
2025-Q42025-12-31414,264,00044,691,000derived Q4 = FY annual - nine-month YTD
2026-Q12026-03-31497,570,00063,456,0001.03reported discrete quarter

Quarterly Charts

NWE quarterly revenue, last 11 periods. Source: SEC companyfacts 2026-Q1.NWE quarterly revenue, last 11 periods. Source: SEC companyfacts 2026-Q1.NWE Quarterly RevenueLatest point: 2026-Q1 = $497.6MSource: SEC companyfacts 2026-Q1.Fiscal quarterQuarterly Revenue$0.0B$250.0M$500.0M2023-Q32023-Q42024-Q12024-Q22024-Q32024-Q42025-Q12025-Q22025-Q32025-Q42026-Q1

Figure provenance: SEC companyfacts. Latest point: FY 2026 ended 2026-03-31; accession 0001993004-26-000029; filed 2026-04-30. Concept: Revenues. Source concepts: us-gaap:Revenues.

NWE quarterly net income, last 11 periods. Source: SEC companyfacts 2026-Q1.NWE quarterly net income, last 11 periods. Source: SEC companyfacts 2026-Q1.NWE Quarterly Net incomeLatest point: 2026-Q1 = $63.5MSource: SEC companyfacts 2026-Q1.Fiscal quarterQuarterly Net income$0.0B$125.0M$250.0M2023-Q32023-Q42024-Q12024-Q22024-Q32024-Q42025-Q12025-Q22025-Q32025-Q42026-Q1

Figure provenance: SEC companyfacts. Latest point: FY 2026 ended 2026-03-31; accession 0001993004-26-000029; filed 2026-04-30. Concept: NetIncomeLoss. Source concepts: us-gaap:NetIncomeLoss.

NWE quarterly diluted eps, last 8 periods. Source: SEC companyfacts 2026-Q1.NWE quarterly diluted eps, last 8 periods. Source: SEC companyfacts 2026-Q1.NWE Quarterly Diluted EPSLatest point: 2026-Q1 = $1.03/shareSource: SEC companyfacts 2026-Q1.Fiscal quarterQuarterly Diluted EPS (USD/share)$0.00/share$0.75/share$1.50/share2023-Q32024-Q12024-Q22024-Q32025-Q12025-Q22025-Q32026-Q1

Figure provenance: SEC companyfacts. Latest point: FY 2026 ended 2026-03-31; accession 0001993004-26-000029; filed 2026-04-30. Concept: EarningsPerShareDiluted. Source concepts: us-gaap:EarningsPerShareDiluted.

Macro Cross-References

Latest quarter (10-Q)

Latest 10-Q source: 0001993004-26-000029.

Extracted structurally from real Item 2 body heading to real Item 3/4 boundary. Confidence: high. Filing date: 2026-04-30. Report date: 2026-03-31.

ITEM 2.MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

Non-GAAP Financial Measure

The following discussion includes financial information prepared in accordance with GAAP, as well as another financial measure, Utility Margin, that is considered a “non-GAAP financial measure.” Generally, a non-GAAP financial measure is a numerical measure of a company’s financial performance, financial position or cash flows that excludes (or includes) amounts that are included in (or excluded from) the most directly comparable measure calculated and presented in accordance with GAAP. We define Utility Margin as Operating Revenues less fuel, purchased supply and direct transmission expense (exclusive of depreciation and depletion) as presented in our Condensed Consolidated Statements of Income. This measure differs from the GAAP definition of Gross Margin due to the exclusion of Operating and maintenance, Property and other taxes, and Depreciation and depletion expenses, which are presented separately in our Condensed Consolidated Statements of Income. The following discussion includes a reconciliation of Utility Margin to Gross Margin, the most directly comparable GAAP measure.

We believe that Utility Margin provides a useful measure for investors and other financial statement users to analyze our financial performance in that it excludes the effect on total revenues caused by volatility in energy costs and associated regulatory mechanisms. This information is intended to enhance an investor's overall understanding of results. Under our various state regulatory mechanisms, as detailed below, our supply costs are generally collected from customers. In addition, Utility Margin is used by us to determine whether we are collecting the appropriate amount of energy costs from customers to allow for recovery of operating costs, as well as to analyze how changes in loads (due to weather, economic or other conditions), rates and other factors impact our results of operations. Our Utility Margin measure may not be comparable to that of other companies' presentations or more useful than the GAAP information provided elsewhere in this report.

OVERVIEW

NorthWestern Energy Group, doing business as NorthWestern Energy, provides electricity and/or natural gas to approximately 850,300 customers in Montana, South Dakota, Nebraska and Yellowstone National Park. Our operations in Montana and Yellowstone National Park are conducted through our subsidiary, NW Corp, and our operations in South Dakota and Nebraska are conducted through our subsidiary, NWE Public Service. For a discussion of NorthWestern’s business strategy, see Management’s Discussion and Analysis of Financial Condition and Results of Operations in the NorthWestern Energy Group Annual Report on Form 10-K for the year ended December 31, 2025.

On August 18, 2025, we entered into the Merger Agreement with Black Hills and Merger Sub that provides for an all-stock merger of equals between NorthWestern and Black Hills. The Merger Agreement provides for Merger Sub to merge with and into NorthWestern, with NorthWestern continuing as the surviving entity and a direct wholly owned subsidiary of Black Hills, which would assume a new corporate name of Bright Horizon Energy as the resulting parent company of the combined corporate group. The Merger will combine the strengths of both companies, resulting in an organization with greater scale, financial stability, and operational expertise. It is designed to create a stronger, more resilient energy company focused on delivering safe, reliable, and affordable energy solutions to customers. Under the provisions of Accounting Standards Codification Topic 805, which requires the identification of an acquirer in a business combination, Black Hills is the accounting acquirer. Pursuant to the Merger Agreement, at the effective time of the Merger, each share of common stock of NorthWestern issued and outstanding as of immediately prior to closing will be converted into the right to receive 0.98 validly issued, fully paid and non-assessable shares of Black Hills Common Stock. See Note 2 - Pending Merger with Black Hills Corporation to the Condensed Consolidated Financial Statements included herein for additional information regarding this pending Merger.

We work to deliver safe, reliable, and innovative energy solutions that create value for customers, communities, employees, and investors. We do this by providing low-cost and reliable service performed by highly-adaptable and skilled employees. We are focused on delivering long-term shareholder value through:

•Infrastructure investment focused on a stronger and smarter grid to improve the customer experience, while enhancing grid reliability and safety. This includes automation in customer meters, distribution and substations that enables the use of proven new technologies.

•Investing in and integrating supply resources that balance reliability, cost, capacity, and sustainability considerations with more predictable long-term commodity prices.

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•Continually improving our operating efficiency. Financial discipline is essential to earning our authorized return on invested capital and maintaining a strong balance sheet, stable cash flows, and quality credit ratings to continue to attract cost-effective capital for future investment.

We expect to pursue these investment opportunities and manage our business in a manner that allows us to be flexible in adjusting to changing economic conditions by adjusting the timing and scale of the projects.

We are committed to providing customers with reliable and affordable electric and natural gas services while also being good stewards of the environment. Towards this end, our efforts towards a carbon-free future are outlined through our goal to achieve net zero carbon emissions by 2050.

As you read this discussion and analysis, refer to our Condensed Consolidated Statements of Income, which present the results of our operations for the three months ended March 31, 2026 and 2025.

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HOW WE PERFORMED AGAINST OUR FIRST QUARTER 2025 RESULTS

Three Months Ended March 31, 2026 vs. 2025
Income Before Income TaxesIncome Tax (Expense) Benefit(3)Net Income
(in millions)
First Quarter, 2025$92.1$(15.2)$76.9
Variance in revenue and fuel, purchased supply, and direct transmission expense(1) items impacting net income:
Rates23.7(6.0)17.7
Electric margin from the acquisition of the Colstrip Puget Interests5.5(1.4)4.1
Production tax credits, offset within income tax expense2.6(2.6)
Electric transmission revenue2.2(0.6)1.6
Non-recoverable Montana electric supply costs2.0(0.5)1.5
Electric retail volumes(12.2)3.1(9.1)
Natural gas retail volumes(6.2)1.6(4.6)
Montana property tax tracker collections(3.3)0.8(2.5)
Natural gas production step down(0.7)0.2(0.5)
Other4.0(1.0)3.0
Variance in expense items(2) impacting net income:
Operating, maintenance, and administrative, excluding merger-related costs(20.0)5.1(14.9)
Depreciation(4.4)1.1(3.3)
Interest expense(3.4)0.9(2.5)
Property and other taxes not recoverable within trackers(2.0)0.5(1.5)
Merger-related costs(3.4)0.5(2.9)
Other0.8(0.3)0.5
First Quarter, 2026$77.3$(13.8)$63.5
Change in Net Income$(13.4)

(1) Exclusive of depreciation and depletion shown separately below

(2) Excluding fuel, purchased supply, and direct transmission expense

(3) Income tax expense calculation on reconciling items assumes a blended federal plus state effective tax rate of 25.3 percent.

Consolidated net income for the three months ended March 31, 2026 was $63.5 million as compared with $76.9 million for the same period in 2025. This decrease was primarily due to retail volumes, operating, administrative, and general costs, including merger-related costs and costs associated with our additional ownership interests in Colstrip Units 3 and 4, depreciation expense, and interest expense. These were offset in part by new rates, transmission revenues, and lower non-recoverable Montana electric supply costs.

SIGNIFICANT TRENDS AND REGULATION

Refer to the NorthWestern Energy Group Annual Report on the Form 10-K for the year ended December 31, 2025 for disclosure of the significant trends and regulations that could have a significant impact on our business. These significant trends and regulations have not changed materially since such disclosure, except as follows:

Montana Rate Review

In December 2025, the MPSC issued a final order approving our partial electric settlement agreement. The final order also suspended the 90/10 cost sharing mechanism of the Power Cost and Credit Adjustment Mechanism (PCCAM) on a temporary basis pending further review by the MPSC. Within this final order, the MPSC disallowed a portion of the capital costs related to

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the construction of Yellowstone County Generating Station (YCGS). As a result, in the fourth quarter of 2025 we recorded a $30.9 million non-cash charge for the regulatory disallowance.

In January 2026, we filed a Motion for Reconsideration (Motion) as it relates to this final order. Among other things, our Motion requests that the MPSC reconsider their prudence conclusions regarding the capital costs associated with the construction of YCGS and clarification as to the effective date of the PCCAM sharing mechanism suspension, for which we have requested an effective date of July 1, 2025, to align with the PCCAM tracker year. Any subsequent modifications by the MPSC to their final order will be reflected in our 2026 results.

Montana Large New Load Tariff Rule

In March 2026, we filed an application with the MPSC requesting approval of a Large New Load tariff rule (LNL Rule) to establish requirements and contract terms for providing electric service to bundled customers with new or expanded loads of five megawatts or greater, including data centers and other energy-intensive operations. This filing establishes a framework governing agreements between us and large new load customers and is intended to address the costs and operational considerations associated with serving those loads while protecting existing customers from cost shifting and other adverse impacts. Under this proposed framework, for the largest commitments, 50 megawatts or greater, we would file the executed Electric Service Agreement with the MPSC for review and approval before service begins. For customers with loads between 5 and 49 megawatts, the tariff's standardized process and mandatory protections apply, but individual agreements do not require case-specific MPSC approval filings. This application initiates a public regulatory proceeding that will include opportunities for review and public comment consistent with MPSC procedures.

Data Center Development

As previously disclosed, we have signed development agreements with both Sabey Data Centers and Atlas Power Holdings LLC to provide electric supply services for data centers being developed in Montana. In April 2026, we signed a development agreement with Quantica Infrastructure to evaluate the transmission infrastructure and generation resources needed to support their proposed need. The combined energy service requirement associated with these development agreements is currently expected to be 150 megawatts beginning in late 2027, with growth of up to approximately 1

[Excerpt truncated for page length; source filing is linked above.]

Latest 10-K MD&A

Extracted structurally from real Item 7 body heading to real Item 7A/8 boundary. Confidence: high. Filing date: 2026-02-12. Report date: 2025-12-31.

ITEM 7. MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

The following includes a discussion of our results of operations and cash flows for the year ended December 31, 2025 compared to the year ended December 31, 2024, on both a consolidated basis and on a segment basis. For a discussion of our financial results and cash flows for the year ended December 31, 2024 compared with the year ended December 31, 2023, see Management's Discussion and Analysis of Financial Condition and Results of Operations in our Annual Report on Form 10-K for the year ended December 31, 2024.

This discussion should be read in conjunction with our Consolidated Financial Statements and related notes contained elsewhere in this Annual Report on Form 10-K. For additional information related to our segments, see Note 22 - Segment and Related Information, to the Consolidated Financial Statements.

Non-GAAP Financial Measure

The following discussion includes financial information prepared in accordance with GAAP, as well as another financial measure, Utility Margin, that is considered a “non-GAAP financial measure.” Generally, a non-GAAP financial measure is a numerical measure of a company’s financial performance, financial position or cash flows that excludes (or includes) amounts that are included in (or excluded from) the most directly comparable measure calculated and presented in accordance with GAAP. We define Utility Margin as Operating Revenues less fuel, purchased supply and direct transmission expense (exclusive of depreciation and depletion) as presented in our Consolidated Statements of Income. This measure differs from the GAAP definition of Gross Margin due to the exclusion of Operating and maintenance, Property and other taxes, and Depreciation and depletion expenses, which are presented separately in our Consolidated Statements of Income. The following discussion includes a reconciliation of Utility Margin to Gross Margin, the most directly comparable GAAP measure.

We believe that Utility Margin provides a useful measure for investors and other financial statement users to analyze our financial performance in that it excludes the effect on total revenues caused by volatility in energy costs and associated regulatory mechanisms. This information is intended to enhance an investor's overall understanding of results. Under our various state regulatory mechanisms, as detailed below, our supply costs are generally collected from customers. In addition, Utility Margin is used by us to determine whether we are collecting the appropriate amount of energy costs from customers to allow for recovery of operating costs, as well as to analyze how changes in loads (due to weather, economic or other conditions), rates and other factors impact our results of operations. Our Utility Margin measure may not be comparable to that of other companies' presentations or more useful than the GAAP information provided elsewhere in this report.

OVERVIEW

NorthWestern Energy Group, doing business as NorthWestern Energy, provides electricity and/or natural gas to approximately 850,300 customers in Montana, South Dakota, Nebraska, and Yellowstone National Park. Our operations in Montana and Yellowstone National Park are conducted through our subsidiary, NW Corp, and our operations in South Dakota and Nebraska are conducted through our subsidiary, NWE Public Service. As you read this discussion and analysis, refer to our Consolidated Statements of Income, which present the results of our operations for 2025, 2024 and 2023. Following is a discussion of our strategy and significant trends.

On August 18, 2025, we entered into the Merger Agreement with Black Hills and Merger Sub that provides for an all-stock merger of equals between NorthWestern and Black Hills. The Merger Agreement provides for Merger Sub to merge with and into NorthWestern, with NorthWestern continuing as the surviving entity and a direct wholly owned subsidiary of Black Hills, which would assume the new corporate name of Bright Horizon Energy as the resulting parent company of the combined corporate group. The Merger will combine the strengths of both companies, resulting in an organization with greater scale, financial stability, and operational expertise. It is designed to create a stronger, more resilient energy company focused on delivering safe, reliable, and affordable energy solutions to customers. Under the provisions of ASC Topic 805, which requires the identification of an acquirer in a business combination, Black Hills is the accounting acquirer. Pursuant to the Merger Agreement, at the effective time of the Merger, each share of common stock of NorthWestern issued and outstanding as of immediately prior to closing will be converted into the right to receive 0.98 validly issued, fully paid and non-assessable shares of Black Hills Common Stock. See Note 3 - Pending Merger with Black Hills Corporation to the Consolidated Financial Statements included herein for additional information regarding this pending Merger.

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We work to deliver safe, reliable and innovative energy solutions that create value for customers, communities, employees, and investors. We do this by providing low-cost and reliable service performed by highly-adaptable and skilled employees. We are focused on delivering long-term shareholder value through:

•Infrastructure investment focused on a stronger and smarter grid to improve the customer experience, while enhancing grid reliability and safety. This includes automation in customer meters, distribution and substations that enables the use of proven new technologies.

•Investing in and integrating supply resources that balance reliability, cost, capacity, and sustainability considerations with more predictable long-term commodity prices.

•Continually improving our operating efficiency. Financial discipline is essential to earning our authorized return on invested capital and maintaining a strong balance sheet, stable cash flows, and quality credit ratings to continue to attract cost-effective capital for future investment.

We expect to pursue these investment opportunities and manage our business in a manner that allows us to be flexible in adjusting to changing economic conditions by adjusting the timing and scale of the projects.

In 2025, approximately 52 percent of our owned and long-term contracted resources originated from carbon-free resources, compared to approximately 41 percent for the total U.S. electric power industry. We are committed to providing customers with reliable and affordable electric and natural gas services while also being good stewards of the environment. Towards this end, our efforts towards a carbon-free future are outlined through our goal to achieve net zero carbon emissions by 2050. Our vision for the future builds on the progress we have made, including our hydroelectric system in Montana, which is 100 percent carbon free and is readily available capacity. For us, wind generation is a close second and continues to grow. While utility-scale solar energy has not been a significant portion of our energy mix to date, we expect solar to further evolve along with advances in energy storage. We are committed to working with our customers and communities to help them achieve their sustainability goals and add new technology on our system.

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HOW WE PERFORMED IN 2025 COMPARED TO OUR 2024 RESULTS

Year Ended December 31, 2025 vs. 2024
Income Before Income TaxesIncome Tax Benefit (Expense)Net Income
(in millions)
December 31, 2024$214.7$9.4$224.1
Variance in revenue and fuel, purchased supply, and direct transmission expense(1) items impacting net income:
Base Rates93.3(23.6)69.7
Electric transmission revenue14.0(3.5)10.5
Production tax credits, offset within income tax benefit (expense)6.6(6.6)
Montana natural gas transportation4.8(1.2)3.6
Electric retail volumes4.3(1.1)3.2
Natural gas retail volumes2.0(0.5)1.5
Montana property tax tracker collections(14.2)3.6(10.6)
Non-recoverable Montana electric supply costs(7.3)1.8(5.5)
Other0.10.00.1
Variance in expense items(2) impacting net income:
Operating, maintenance, and administrative(37.7)9.5(28.2)
Non-cash regulatory disallowance of certain YCGS capital costs(30.9)7.8(23.1)
Depreciation(21.9)5.5(16.4)
Interest expense(18.7)4.7(14.0)
Merger-related costs(9.3)(9.3)
Property and other taxes not recoverable within trackers(2.1)0.5(1.6)
Release of unrecognized tax benefits - current year7.47.4
Release of unrecognized tax benefits - prior year(16.9)(16.9)
Prior year Gas repairs safe harbor method change(7.0)(7.0)
Other(10.1)3.7(6.4)
December 31, 2025$187.6$(6.5)$181.1
Change in Net Income$(43.0)

(1) Exclusive of depreciation and depletion shown separately below.

(2) Excluding fuel, purchased supply, and direct transmission expense.

Consolidated net income in 2025 was $181.1 million as compared with $224.1 million in 2024. This decrease was primarily due to higher operating expenses, including a non-cash charge for the regulatory disallowance of certain YCGS capital costs resulting from the MPSC's final order on our rate review, merger-related costs, and depreciation, interest expense, Montana property tax tracker collections, non-recoverable Montana electric supply costs, and higher income tax expense due to a less favorable uncertain tax position release and a prior year income tax benefit from a gas repairs safe harbor method change. These were partly offset by higher rates, electric transmission revenue, natural gas transportation revenues, and retail volumes.

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SIGNIFICANT TRENDS AND REGULATION

Montana Rate Review

In July 2024, we filed a Montana electric and natural gas rate review with the MPSC requesting an annual increase to electric and natural gas utility rates. In December 2025, the MPSC issued a final order approving the natural gas settlement agreement and partial electric settlement agreement. Among other things, the approved partial electric settlement agreement provides for the deferral and annual recovery of incremental operating costs related to wildfire mitigation and insurance expenses through the Wildfire Mitigation Balancing Account.

The details of this final order are set forth below:

Returns, Capital Structure & Revenue Increase Resulting From Final Order ($ in millions)
ElectricNatural Gas
Return on Equity (ROE)9.65%9.60%
Equity Capital Structure47.84%47.84%
Base Rates$105.5$18.0
PCCAM(1)(2)(94.5)n/a
Property Tax (tracker base adjustment)(1)(1.8)0.1
Total Revenue Increase Through Final Order$9.2$18.1

(1) These items are flow-through costs. PCCAM reflects our fuel and purchased power costs.

(2) This PCCAM reduction of $94.5 million represents the reduction in revenue at the previously approved 2021 PCCAM base of $208.3 million using the 2023 Montana rate review test period loads.

The final order provides for an update to the PCCAM by adjusting the base costs from $208.3 million to $119.0 million. It also suspended the 90/10 cost sharing mechanism of the PCCAM on a temporary basis pending further review by the MPSC. Within this final order, the MPSC disallowed a portion of the capital costs related to the construction of YCGS. As a result, in the fourth quarter of 2025 we recorded a $30.9 million non-cash charge for the regulatory disallowance within Operating and maintenance on the Consolidated Statements of Income and a corresponding reduction to Property, plant, and equipment, net on the Consolidated Balance Sheets. As of December 31, 2025, we have deferred $7.7 million of base rate revenues collected that will be refunded to customers.

In January 2026, we filed a Motion for Reconsideration (Motion) as it relates to this final order. Among other things, our Motion requests that the MPSC reconsider their prudence conclusions regarding the capital costs associated with the construction of YCGS and clarification as to the effective date of the PCCAM sharing mechanism suspension, of which we have requested an effective date of July 1, 2025, to align with the PCCAM tracker year.

Montana Large-Load Tariff

The MPSC requested information on our plan to serve potential large-load customers and related resource adequacy issues. We responded in March 2025, outlining our policy and legal positions, emphasizing the importance of economic development for Montana and our commitment to serving our existing customers. We expect to submit a filing with the MPSC during the first half of 2026 to address data center development discussed below, incorporating rate design that prevents cost shifting of infrastructure upgrades needed to serve large-load customers to other retail customers.

Data Center Development

In July 2025, we entered into a nonbinding letter of intent with Quantica Infrastructure to evaluate the transmission infrastructure and generation resources needed to support their proposed need. We had previously disclosed, in December 2024, two separate nonbinding letters of intent with Sabey Data Centers (Sabey) and Atlas Power Holdings LLC (Atlas) to provide electric supply services for data centers being developed in Montana. The combined energy service requirement associated with these letters of intent is currently expected to be 175 megawatts beginning in late 2027, or earlier, with growth of up to 1,100 megawatts or more by 2030. We have signed development agreements with both Sabey and Atlas and are working with each of these parties to execute electric service agreements.

Resources and regulatory mechanisms to be utilized for serving these requests are pending further evaluation and regulatory considerations.

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Colstrip Acquisitions and Requests for Cost Recovery

As previously disclosed, we entered into definitive agreements with Avista and Puget to acquire their respective interests in Colstrip Units 3 and 4 for $0 and completed these acquisitions on January 1, 2026. Accordingly, we are responsible for the associated operating costs beginning on January 1, 2026, which we will not collect through utility base rates until requested in a future Montana rate review. Puget and Avista will remain responsible for their respective pre-closing share of environmental and pension liabilities attributed to events or conditions existing prior to the closing of the transaction and for any future decommissioning and demolition costs associated with the existing facilities that comprise their interests.

Avista Interests - The 222 megawatts of generation capacity from Colstrip Units 3 and 4 acquired from Avista (Avista Interests) on January 1, 2026, was identified as a key element in our strategy to achieve resource adequacy for customers, as outlined in our 2023 Montana Integrated Resource Plan. Noting the costs associated with operating this resource are not currently reflected in utility customer rates, in August 2025, we filed a temporary PCCAM tariff waiver request with the MPSC that would provide a near-term cost-recovery mechanism expected to largely offset approximately $18.0 million in annual incremental operating and maintenance costs associated with the Avista Interests. This waiver requested that the MPSC allow us to keep 100 percent of the net revenue associated with certain designated power sales contracts up to the amount of the operating and maintenance expenses we incur associated with our Avista Interests. Furthermore, the waiver request indicated that any net revenues from the designated contracts exceeding the operating and maintenance expenses associated with our Avista Interests would continue to flow back to retail customers. In January 2026, the MPSC approved our PCCAM tariff waiver request on an interim basis with final approval or denial subject to the ongoing PCCAM docket process.

Puget Interests - The 370 megawatts of generation capacity from Colstrip Units 3 and 4 acquired from Puget (Puget Interests) on January 1, 2026, increases our ownership share of the facility to 55 percent and provides an increase in voting share in determining strategic direction and investment decisions at the facility. While we expect our future opportunity to serve growing customer demand, including large-load customers, may be supported by this resource, in October 2025, we signed a contract to sell the dispatchable capacity and associated energy from the Puget Interests beginning January 1, 2026, through late 2027. Revenues from this agreement are expected to largely offset the estimated $30.0 million of annual incremental operating and maintenance costs associated with the Puget Interests. In addition, in October 2025, we submitted a request to the FERC for approval of cost-based rates for our subsidiary that will own the Puget Interests. We expect this rate approval to be effective in the first quarter of 2026. If our request for rates effective January 1, 2026 is not approved, we could incur refund liability for contract revenues received during the unauthorized period.

Generation Capacity in South Dakota

The SPP has recently updated its resource accreditation and PRM requirements in response to growing reliability concerns. As a result, SPP is requiring additional accredited capacity by 2030 to meet the updated PRM targets. In October 2025, we submitted a project with the SPP under their Expedited Resource Adequacy Study program for the construction of a 131 MW natural gas generating facility located in Aberdeen, South Dakota, to meet regional capacity needs by 2030. Anticipated costs for this project are approximately $300.0 million.

Regional Transmission Development Activities

In December 2024, we signed a nonbinding memorandum of understanding (MOU) with North Plains Connector LLC, a wholly owned subsidiary of Grid United, to own 10 percent (300 megawatts) of the NPC Consortium project. The project is entering the permitting phase. Currently, construction is planned to commence in 2028, subject to receipt of regulatory approvals, with the project expected to be operational by 2032. Under the terms of the MOU, Grid United will continue to fund the development of the NPC and we will make our investment decision when the regulatory approvals and permits are in place. The project is a critical infrastructure investment that aligns with our commitment to providing reliable and affordable energy to our customers while also supporting broader grid resilience efforts in the region.

We have also entered into a nonbinding letter of intent with Grid United to continue transmission development to further enhance the grid through the southwest corridor of Montana. Development to expand the southwest corridor of Montana through grid build out would represent a significant step in enhancing connectivity between Montana and the broader Western energy market - bolstering grid reliability, allowing for critical import capability, and enabling customers to access and benefit from emerging energy markets in the West.

Montana Wildfire Risk Mitigation

The Montana Legislature approved House Bill 490 in April 2025. It precludes common law strict liability claims for damages related to wildfire and electric activities or wildfire mitigation activities; establishes a statutory standard of care,

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supplanting common law causes of action and other theories of recovery; and creates a rebuttable presumption that an electric facilities provider acted reasonably if it substantially followed an approved wildfire mitigation plan. The legislation also defines the availability of damages by allowing noneconomic personal injury damages only when there is bodily injury and punitive damages only when an injured party proves by clear and convincing evidence that an electric facilities provider's actions were grossly negligent or intentional. The MPSC approved our wildfire mitigation plan in November 2025. The wildfire mitigation plan for the Colstrip transmission system was submitted to the MPSC on November 7, 2025, and we anticipate a decision in the first quarter of 2026.

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SIGNIFICANT INFRASTRUCTURE INVESTMENTS AND INITIATIVES

Our estimated capital expenditures for the next five years, including our electric and natural gas transmission and distribution and electric generation infrastructure investment plan, are as follows (in millions):

Electric Supply Resource Plans - Our energy resource plans identify portfolio resource requirements including potential investments. For additional information related to our electric supply resource plans, see Item 1. Business, where we discuss electric resource planning for our Montana and South Dakota jurisdictions.

Distribution and Transmission Modernization and Maintenance - The primary goals of our infrastructure investments are to reverse the trend in aging infrastructure, maintain reliability, proactively manage safety, build capacity into the system, and prepare our network for the adoption of new technologies. We are taking a proactive and pragmatic approach to replacing these assets while also evaluating the implementation of additional technologies to prepare the overall system for smart grid applications. Approximately $2.3 billion, or 70 percent, of our capital forecast above is projected to be spent on our distribution and transmission system. In 2025, we completed the installation, which began in 2021, of automated metering infrastructure in Montana.

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RESULTS OF OPERATIONS

Our consolidated results include the results of our divisions and subsidiaries constituting each of our business segments. The overall consolidated discussion is followed by a detailed discussion of utility margin by segment.

Factors Affecting Results of Operations

Our revenues may fluctuate substantially with changes in supply costs, which are generally collected in rates from customers. In addition, various regulatory agencies approve the prices for electric and natural gas utility service within their respective jurisdictions and regulate our ability to recover costs from customers.

Revenues are also impacted by customer growth and usage, the latter of which is primarily affected by weather and the impact of energy efficiency initiatives and investment. Very cold winters increase demand for natural gas and to a lesser extent, electricity, while warmer than normal summers increase demand for electricity, especially among our residential customers. We measure this effect based on the number of customers, temperature variances, and the amount of electricity or natural gas historically used per degree of temperature. Degree-day, which is the difference between the average daily actual temperature and a baseline temperature of 65 degrees, is used to estimate the amount of energy required to maintain comfortable indoor temperature levels based on each day's average temperature. Heating degree-days result when the average daily temperature is less than the baseline. Cooling degree-days result when the average daily temperature is greater than the baseline. The statistical weather information in our regulated segments represents a comparison of this data.

Fuel, purchased supply and direct transmission expenses are costs directly associated with the generation and procurement of electricity and natural gas. These costs are generally collected in rates from customers and may fluctuate substantially with market prices and customer usage.

Operating and maintenance expenses are costs associated with the ongoing operation of our vertically-integrated utility facilities which provide electric and natural gas utility products and services to our customers. Among the most significant of these costs are those associated with direct labor and supervision, repair and maintenance expenses, and contract services. These costs are normally fairly stable across broad volume ranges and therefore do not normally increase or decrease significantly in the short term with increases or decreases in volumes.

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OVERALL CONSOLIDATED RESULTS

Year Ended December 31, 2025 Compared with Year Ended December 31, 2024

Consolidated net income in 2025 was $181.1 million as compared with $224.1 million in 2024, a decrease of $43.0 million. This decrease was primarily due to higher operating expenses, including a non-cash charge for the regulatory disallowance of certain YCGS capital costs resulting from the MPSC's final order on our rate review, merger-related costs, and depreciation, interest expense, Montana property tax tracker collections, non-recoverable Montana electric supply costs, and higher income tax expense due to a less favorable uncertain tax position release and a prior year income tax benefit from a gas repairs safe harbor method change. These were partly offset by higher rates, electric transmission revenue, natural gas transportation revenues, and retail volumes.

Consolidated gross margin in 2025 was $484.3 million as compared with $460.8 million in 2024, an increase of $23.5 million or 5.1 percent. This increase was primarily due to higher rates, electric transmission revenue, natural gas transportation revenues, and retail volumes. These were partly offset by higher operating expenses, including a non-cash charge for the regulatory disallowance of certain YCGS capital costs resulting from the MPSC's final order on our rate review and depreciation, Montana property tax tracker collections, and non-recoverable Montana electric supply costs.

ElectricNatural GasTotal
202520242025202420252024
(in millions)
Reconciliation of gross margin to utility margin:
Operating Revenues$1,270.0$1,200.7$340.6$313.2$1,610.6$1,513.9
Less: Fuel, purchased supply and direct transmission expense (exclusive of depreciation and depletion shown separately below)306.6329.6103.2104.2409.8433.8
Less: Operating and maintenance224.4171.760.556.1284.9227.8
Less: Property and other taxes140.9126.541.237.4182.1163.9
Less: Depreciation and depletion208.6190.040.937.6249.5227.6
Gross Margin389.5382.994.877.9484.3460.8
Operating and maintenance224.4171.760.556.1284.9227.8
Property and other taxes140.9126.541.237.4182.1163.9
Depreciation and depletion208.6190.040.937.6249.5227.6
Utility Margin(1)$963.4$871.1$237.4$209.0$1,200.8$1,080.1

(1) Non-GAAP financial measure. See "Non-GAAP Financial Measure" above.

Year Ended December 31,
20252024Change% Change
(in millions)
Utility Margin
Electric$963.4$871.1$92.310.6%
Natural Gas237.4209.028.413.6
Total Utility Margin(1)$1,200.8$1,080.1$120.711.2%

(1) Non-GAAP financial measure. See "Non-GAAP Financial Measure" above.

Consolidated utility margin in 2025 was $1,200.8 million as compared with $1,080.1 million in 2024, an increase of $120.7 million, or 11.2 percent.

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Primary components of the change in utility margin include the following (in millions):

Utility Margin2025 vs. 2024
Utility Margin Items Impacting Net Income
Base Rates$93.3
Electric transmission revenue due to market conditions and rates14.0
Montana natural gas transportation4.8
Electric retail volumes4.3
Natural gas retail volumes ($4.2 million due to acquisition of Energy West Operations)2.0
Montana property tax tracker collections(14.2)
Non-recoverable Montana electric supply costs(7.3)
Other0.1
Change in Utility Margin Impacting Net Income97.0
Utility Margin Items Offset Within Net Income
Property and other taxes recovered in revenue, offset in property and other taxes16.3
Production tax credits, offset in income tax expense6.6
Operating expenses recovered in revenue, offset in operating and maintenance expense0.8
Change in Items Offset Within Net Income23.7
Increase in Consolidated Utility Margin(1)$120.7

(1) Non-GAAP financial measure. See "Non-GAAP Financial Measure" above.

Electric retail volumes were driven by favorable weather in South Dakota impacting residential demand, higher Montana commercial demand, and customer growth in all jurisdictions, partly offset by unfavorable weather in Montana, lower commercial demand in South Dakota, and lower industrial demand. Natural gas retail volumes were driven by the acquisition of Energy West, favorable weather in South Dakota and Nebraska, higher commercial demand, and customer growth in all jurisdictions, partly offset by unfavorable weather in Montana.

Under the PCCAM, net supply costs higher or lower than the PCCAM base rate (PCCAM Base) (excluding QF costs) were allocated 90 percent to Montana customers and 10 percent to shareholders. For the twelve months ended December 31, 2025, we under-collected supply costs of $73.9 million resulting in an increase to our under collection of costs, and recorded a decrease in pre-tax earnings of $8.2 million (10 percent of the PCCAM Base cost variance). For the twelve months ended December 31, 2024, we under-collected supply costs of $8.0 million resulting in an increase to our under collection of costs, and recorded a decrease in pre-tax earnings of $0.9 million (10 percent of the PCCAM Base cost variance). As part of the MPSC's final order on our Montana electric rate review they suspended the 90/10 cost sharing mechanism of the PCCAM on a temporary basis pending further review by the MPSC.

Year Ended December 31,
20252024Change% Change
(in millions)
Operating Expenses (excluding fuel, purchased supply and direct transmission expense)
Operating and maintenance$284.9$227.8$57.125.1%
Administrative and general158.2137.420.815.1
Property and other taxes182.3163.918.411.2
Depreciation and depletion249.5227.621.99.6
Total Operating Expenses (excluding fuel, purchased supply and direct transmission expense)$874.9$756.7$118.215.6%

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Consolidated operating expenses, excluding fuel, purchased supply and direct transmission expense, were $874.9 million in 2025, as compared with $756.7 million in 2024. Primary components of the change include the following (in millions):

Operating Expenses
2025 vs. 2024
Operating Expenses (excluding fuel, purchased supply and direct transmission expense) Impacting Net Income
Non-cash regulatory disallowance of certain YCGS capital costs$30.9
Depreciation expense due to plant additions and higher depreciation rates21.9
Electric generation maintenance9.9
Merger-related costs, primarily including consulting and legal fees9.3
Wildfire mitigation expense, partly offset by higher base revenues8.9
Insurance expense, primarily due to increased wildfire risk premiums7.8
Labor and benefits(1)7.6
Technology implementation and maintenance3.5
Property and other taxes not recoverable within trackers2.1
Uncollectible accounts1.1
Litigation outcome (Pacific Northwest Solar)(2.4)
Non-cash impairment of alternative energy storage investment(1.7)
Other3.0
Change in Items Impacting Net Income101.9
Operating Expenses Offset Within Net Income
Property and other taxes recovered in trackers, offset in revenue16.3
Deferred compensation, offset in other income2.1
Operating and maintenance expenses recovered in trackers, offset in revenue0.8
Pension and other postretirement benefits, offset in other income(1)(2.9)
Change in Items Offset Within Net Income16.3
Increase in Operating Expenses (excluding fuel, purchased supply and direct transmission expense)$118.2

(1) In order to present the total change in labor and benefits, we have included the change in the non-service cost component of our pension and other postretirement benefits, which is recorded within other income on our Condensed Consolidated Statements of Income. This change is offset within this table as it does not affect our operating expenses.

Consolidated operating income in 2025 was $325.8 million as compared with $323.3 million in 2024. This increase was primarily due to new rates, electric transmission revenue, natural gas transportation revenues, and retail volumes. These were partly offset by higher operating, administrative, and general costs, including a non-cash charge for the regulatory disallowance of certain YCGS capital costs resulting from the MPSC's final order on our rate review and merger-related costs, depreciation, Montana property tax tracker collections, and non-recoverable Montana electric supply costs.

Consolidated interest expense in 2025 was $150.4 million, as compared with $131.7 million in 2024. This increase was due to higher borrowings and interest rates, partly offset by lower capitalization of AFUDC.

Consolidated other income in 2025 was $12.1 million, as compared with $23.0 million in 2024. This decrease was primarily due to lower capitalization of AFUDC, a prior year reversal of $2.3 million from a previously disclosed CREP penalty due to a favorable legal ruling, and a $1.3 million expense current year accrual related to an estimated penalty for the CREP informed by a recent MPSC ruling, partly offset by an increase of $2.5 million driven by a prior year non-cash impairment of an alternative energy storage equity investment.

Consolidated income tax expense in 2025 was $6.5 million, as compared to an income tax benefit of $9.4 million in 2024. Our effective tax rate for the twelve months ended December 31, 2025 was 3.5 percent as compared with (4.4)

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percent for the same period of 2024. As further discussed in Note 14 - Income Taxes, income tax expense for the twelve months ended December 31, 2025, includes a $10.4 million benefit related to a reduction in our unrecognized tax benefits, inclusive of $3.0 million of previously accrued interest ($7.4 million net of interest). Income tax benefit for the twelve months ended December 31, 2024, includes a $21.0 million benefit related to a reduction in our unrecognized tax benefits, inclusive of $4.1 million of previously accrued interest ($16.9 million net of interest). Additionally, during the twelve months ended December 31, 2024, we filed a tax accounting method change with the IRS consistent with the guidance for natural gas transmission and distribution property. This resulted in an income tax benefit of $7.0 million during 2024, related to repair costs that were previously capitalized for tax purposes in the 2022 and prior tax years.

We currently estimate our effective tax rate will range between 14.0 percent to 18.0 percent in 2026. Based on the significant NOL income tax position we have, we anticipate paying minimal cash for income taxes into 2029.

The following table summarizes the differences between our effective tax rate and the federal statutory rate (in millions):

Year Ended December 31,
20252024
(in dollars)(in percent)(in dollars)(in percent)
Income before income taxes$187.6$214.7
Income tax calculated at federal statutory rate39.421.0%45.121.0%
State income tax, net of federal provision(1.5)(0.8)0.40.2
Tax Credits
Production tax credits(5.9)(3.2)(11.1)(5.2)
Other0.70.40.70.3
Impact of utility ratemaking on income taxes
Flow-through repairs deductions(31.0)(16.5)(23.1)(10.8)
Amortization of excess deferred income taxes(3.2)(1.7)(2.9)(1.4)
AFUDC, net(1.3)(0.7)(2.6)(1.2)
Plant and depreciation of flow through items16.89.09.44.4
Gas repairs safe harbor method change(7.0)(3.3)
Changes in Unrecognized Tax Benefits
Release of unrecognized tax benefits(7.4)(4.0)(16.9)(7.9)
Interest and penalties(3.0)(1.6)(1.5)(0.7)
Nontaxable and nondeductible items2.91.50.40.2
Other0.00.1(0.3)0.0
(32.9)(17.5)%(54.5)(25.4)%
Income Tax Expense (Benefit) and Effective Tax Rate$6.53.5%$(9.4)(4.4)%

Our effective tax rate typically differs from the federal statutory tax rate primarily due to the regulatory impact of flowing through federal and state tax benefits of repairs deductions, state tax benefit of accelerated tax depreciation deductions (including bonus depreciation when applicable) and production tax credits.

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ELECTRIC OPERATIONS

We have various classifications of electric revenues, defined as follows:

•Retail: Sales of electricity to residential, commercial and industrial customers, and the impact of regulatory mechanisms.

•Regulatory amortization: Primarily represents timing differences for electric supply costs and property taxes between when we incur these costs and when we recover these costs in rates from our customers, which is also reflected in fuel, purchased supply and direct transmission expense and therefore has minimal impact on utility margin. The amortization of these amounts are offset in retail revenue.

•Transmission: Reflects transmission revenues regulated by the FERC.

•Wholesale and other are largely utility margin neutral as they are offset by changes in fuel, purchased supply and direct transmission expense.

Year Ended December 31, 2025 Compared with Year Ended December 31, 2024

RevenuesChangeMWHsAvg. Customer Counts
20252024$%2025202420252024
(in thousands)
Montana$406,643$398,790$7,8532.0%2,8342,804334,011328,420
South Dakota77,89470,0127,88211.358355751,78751,467
Residential484,537468,80215,7353.43,4173,361385,798379,887
Montana408,530408,977(447)(0.1)3,2163,19777,30575,878
South Dakota120,108111,8138,2957.41,0611,09313,19013,084
Commercial528,638520,7907,8481.54,2774,29090,49588,962
Industrial43,12846,637(3,509)(7.5)2,7892,9248080
Other(1)34,51032,8111,6995.214714628,56428,608
Total Retail Electric$1,090,813$1,069,040$21,7732.0%10,63010,721504,937497,537
Regulatory amortization58,26524,90833,357133.9
Transmission111,02497,05213,97214.4
Wholesale and Other9,8549,7011531.6
Total Revenues$1,269,956$1,200,701$69,2555.8%
Fuel, purchased supply and direct transmission expense(2)306,569329,578(23,009)(7.0)
Utility Margin(3)$963,387$871,123$92,26410.6%

(1) Included within this line is our lighting customer class, which we have historically counted each lighting district as one customer. We have retrospectively modified our customer counts to now reflect each lighting service as a customer as that better aligns with the MWH usage of this customer class.

(2) Exclusive of depreciation and depletion.

(3) Non-GAAP financial measure. See “Non-GAAP Financial Measure” above. Also see "Overall Consolidated Results" above for reconciliation of gross margin to utility margin.

Cooling Degree Days2025 as compared with:
20252024Historic Average2024Historic Average
Montana39248546019% cooler15% cooler
South Dakota93877875121% warmer25% warmer

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Heating Degree Days2025 as compared with:
20252024Historic Average2024Historic Average
Montana(1)7,0447,0337,486remained flat6% warmer
South Dakota6,9436,5017,6967% colder10% warmer

(1) Montana electric and natural gas heating degree days may differ due to differences in service territory.

The following summarizes the components of the changes in electric utility margin for the years ended December 31, 2025 and 2024 (in millions):

Utility Margin2025 vs. 2024
Utility Margin Items Impacting Net Income
Base rates$71.8
Electric transmission revenue due to market conditions and rates14.0
Retail volumes4.3
Montana property tax tracker collections(10.8)
Non-recoverable Montana electric supply costs(7.3)
Other(0.1)
Change in Utility Margin Items Impacting Net Income71.9
Utility Margin Items Offset Within Net Income
Property and other taxes recovered in revenue, offset in property and other taxes12.7
Production tax credits, offset in income tax expense6.6
Operating expenses recovered in revenue, offset in operating and maintenance expense1.1
Change in Items Offset Within Net Income20.4
Increase in Utility Margin(1)$92.3

(1) Non-GAAP financial measure. See "Non-GAAP Financial Measure" above. Also see "Overall Consolidated Results" above for reconciliation of gross margin to utility margin.

Electric retail volumes were driven by favorable weather in South Dakota impacting residential demand, higher Montana commercial demand, and customer growth in all jurisdictions, partly offset by unfavorable weather in Montana, lower commercial demand in South Dakota, and lower industrial demand.

For the twelve months ended December 31, 2025, we under-collected supply costs of $73.9 million resulting in an increase to our under collection of costs, and recorded a decrease in pre-tax earnings of $8.2 million (10 percent of the PCCAM Base cost variance). For the twelve months ended December 31, 2024, we under-collected supply costs of $8.0 million resulting in an increase to our under collection of costs, and recorded a decrease in pre-tax earnings of $0.9 million (10 percent of the PCCAM Base cost variance). As part of the MPSC's final order on our Montana electric rate review they suspended the 90/10 cost sharing mechanism of the PCCAM on a temporary basis pending further review by the MPSC.

The change in regulatory amortization revenue is due to timing differences between when we incur electric supply costs and when we recover these costs in rates from our customers, which has a minimal impact on utility margin. Our wholesale and other revenues are largely utility margin neutral as they are offset by changes in fuel, purchased supply and direct transmission expenses.

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NATURAL GAS OPERATIONS

We have various classifications of natural gas revenues, defined as follows:

•Retail: Sales of natural gas to residential, commercial and industrial customers, and the impact of regulatory mechanisms.

•Regulatory amortization: Primarily represents timing differences for natural gas supply costs and property taxes between when we incur these costs and when we recover these costs in rates from our customers, which is also reflected in fuel, purchased supply and direct transmission expenses and therefore has minimal impact on utility margin. The amortization of these amounts are offset in retail revenue.

•Wholesale: Primarily represents transportation and storage for others.

Year Ended December 31, 2025 Compared with Year Ended December 31, 2024

RevenuesChangeDekathermsAvg. Customer Counts
20252024$%2025202420252024
(in thousands)
Montana$120,830$110,21510,6159.6%14,33913,749201,728185,644
South Dakota28,94826,8842,0647.73,0322,70942,95242,577
Nebraska25,73321,2054,52821.42,4142,29437,97037,958
Residential175,511158,30417,20710.919,78518,752282,650266,179
Montana68,72259,9258,79714.78,6917,78228,38026,164
South Dakota21,57418,0693,50519.43,3032,7917,5867,383
Nebraska13,78411,4322,35220.61,7381,6645,1145,056
Commercial104,08089,42614,65416.413,73212,23741,08038,603
Industrial2,4391,0411,398134.32,140147241237
Other1,3501,352(2)(0.1)197207218197
Total Retail Gas$283,380$250,123$33,25713.3%35,85431,343324,189305,216
Regulatory amortization(305)19,017(19,322)(101.6)
Transportation, wholesale and other57,52844,05713,47130.6
Total Revenues$340,603$313,197$27,4068.8%
Fuel, purchased supply and direct transmission expense(1)103,186104,238(1,052)(1.0)
Utility Margin(2)$237,417$208,959$28,45813.6%

(1) Exclusive of depreciation and depletion.

(2) Non-GAAP financial measure. See “Non-GAAP Financial Measure” above. Also see "Overall Consolidated Results" above for reconciliation of gross margin to utility margin.

Heating Degree Days2025 as compared with:
20252024Historic Average2024Historic Average
Montana(1)7,2077,2657,6971% warmer6% warmer
South Dakota6,9436,5017,6967% colder10% warmer
Nebraska5,7195,2416,0619% colder6% warmer

(1) Montana electric and natural gas heating degree days may differ due to differences in service territory.

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The following summarizes the components of the changes in natural gas utility margin for the years ended December 31, 2025 and 2024 (in millions):

Utility Margin2025 vs. 2024
Utility Margin Items Impacting Net Income
Base rates$21.5
Montana natural gas transportation4.8
Retail volumes ($4.2 million due to acquisition of Energy West Operations)2.0
Montana property tax tracker collections(3.4)
Other0.2
Change in Utility Margin Impacting Net Income25.1
Utility Margin Items Offset Within Net Income
Property and other taxes recovered in revenue, offset in property and other taxes3.6
Operating expenses recovered in revenue, offset in operating and maintenance expense(0.3)
Change in Items Offset Within Net Income3.3
Increase in Utility Margin(1)$28.4

(1) Non-GAAP financial measure. See "Non-GAAP Financial Measure" above. Also see "Overall Consolidated Results" above for reconciliation of gross margin to utility margin.

Natural gas retail volumes were driven by the acquisition of Energy West, favorable weather in South Dakota and Nebraska, higher commercial demand, and customer growth in all jurisdictions, partly offset by unfavorable weather in Montana.

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LIQUIDITY AND CAPITAL RESOURCES

Liquidity

We require liquidity to support and grow our business, and use our liquidity for working capital needs, capital expenditures, investments in or acquisitions of assets, and to repay debt. For NorthWestern Energy Group, liquidity is primarily provided through its revolving credit facility and dividends from its utility operating subsidiaries, NW Corp and NWE Public Service. These subsidiaries are subject to certain restrictions that may limit the amount of their dividend distributions. See Note 18 - Common Stock to the Consolidated Financial Statements for more information regarding these dividend restrictions.

We believe our cash flows from operations, existing borrowing capacity, debt and equity issuances and future utility rate increases should be sufficient to fund our operations, service existing debt, pay dividends, and fund capital expenditures. We plan to maintain a 50 - 55 percent debt to total capital ratio excluding finance leases, and expect to continue targeting a long-term dividend payout ratio of 60 - 70 percent of earnings per share; however, there can be no assurance that we will be able to meet these targets.

As of December 31, 2025, our total consolidated net liquidity was approximately $229.8 million, including $8.8 million of cash and $221.0 million of revolving credit facility availability with no letters of credit outstanding.

Cash Flows

The following table summarizes our consolidated cash flows (in millions):

Year Ended December 31,
20252024
Operating Activities
Net income$181.1$224.1
Non-cash adjustments to net income289.0213.5
Changes in working capital(61.4)(18.9)
Other noncurrent assets and liabilities(14.2)(11.9)
Cash Provided by Operating Activities394.5406.8
Investing Activities
Property, plant and equipment additions(524.5)(549.3)
Acquisition of Energy West Operations(35.9)
Other investing activity(10.3)(5.2)
Cash Used in Investing Activities(570.7)(554.5)
Financing Activities
Issuance of long-term debt602.1215.0
Issuance of short-term borrowings50.0100.0
Repayments on long-term debt(300.0)(100.0)
Dividends on common stock(161.4)(158.6)
Line of credit (repayments) borrowings , net(9.0)95.0
Financing costs(4.5)(1.1)
Treasury stock activity0.71.2
Cash Provided by Financing Activities177.9151.5
Net Increase in Cash, Cash Equivalents, and Restricted Cash$1.7$3.8
Cash, Cash Equivalents, and Restricted Cash, beginning of period$29.0$25.2
Cash, Cash Equivalents, and Restricted Cash, end of period$30.7$29.0

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Operating Activities

As of December 31, 2025, cash, cash equivalents, and restricted cash were $30.7 million as compared with $29.0 million as of December 31, 2024. Cash provided by operating activities totaled $394.5 million for the year ended December 31, 2025 as compared with $406.8 million for the year ended December 31, 2024. The changes in cash flows from operating activities generally follow the results of operations, as discussed above in the consolidated results of operations for the year ended December 31, 2025, and are affected by changes in working capital. The decrease in cash provided by operating activities is primarily due to merger transaction costs, lower collections of accounts receivable balances due to timing of colder weather, and an increase in our net cash outflows for energy supply costs, as shown in the table below, partly offset by the proceeds from production tax credits transferred.

Net under-collected energy supply costs (in millions)
Beginning of yearEnd of yearNet cash inflows (outflows)
2024$7.8$5.9$1.9
2025$5.9$44.8$(38.9)
Increase in net cash outflows$(40.8)

Investing Activities

Cash used in investing activities totaled $570.7 million during the year ended December 31, 2025, as compared with $554.5 million during 2024. Plant additions during 2025 include capital maintenance additions of approximately $372.7 million and capacity related capital expenditures of approximately $151.8 million. Plant additions during 2024 included capital maintenance additions of approximately $324.0 million and capacity related capital expenditures of approximately $225.3 million. During the year ended December 31, 2025, we completed the acquisition of the Energy West Operations for $35.9 million. See Note 4 - Acquisition of Energy West Operations to the Consolidated Financial Statements included herein for additional information regarding this acquisition. As discussed above in the “Significant Infrastructure Investments and Initiatives” section, our capital expenditures are forecasted to be $683.0 million in 2026.

Financing Activities

Cash provided by financing activities totaled $177.9 million during the year ended December 31, 2025 as compared with $151.5 million during the year ended December 31, 2024. During the year ended December 31, 2025, cash provided by financing activities reflects proceeds from the issuance of long-term debt of $602.1 million and short-term borrowings of $50.0 million, partly offset by repayment of $300.0 million of Montana and South Dakota First Mortgage bonds, payment of dividends of $161.4 million, and net repayments under our revolving lines of credit of $9.0 million. During the year ended December 31, 2024, cash provided by financing activities reflects proceeds from the issuance of long-term debt of $215.0 million, short-term borrowings of $100.0 million, and net issuances under our revolving lines of credit of $95.0 million, partly offset by payment of dividends of $158.6 million and repayment of $100.0 million of Montana First Mortgage Bonds.

Cash Requirements and Capital Resources

We believe our cash flows from operations, existing borrowing capacity, debt and equity issuances and future rate increases should be sufficient to satisfy our material cash requirements over the short-term and the long-term. As a rate-regulated utility our customer rates are generally structured to recover expected operating costs, with an opportunity to earn a return on our invested capital. This structure supports recovery for many of our operating expenses, although there are situations where the timing of our cash outlays results in increased working capital requirements. Due to the seasonality of our utility business, our short-term working capital requirements typically peak during the coldest winter months and warmest summer months when we cover the lag between when purchasing energy supplies and when customers pay for these costs. Our credit facilities may also be utilized for funding cash requirements during seasonally active construction periods, with peak activity during warmer months. Our cash requirements also include a variety of contractual obligations as outlined below in the “Contractual Obligations and Other Commitments” section.

Our material cash requirements are also related to investment in our business through our capital expenditure program, which is discussed above in the “Significant Infrastructure Investments and Initiatives” section. Our capital expenditures are forecasted to be $683 million in 2026, $643 million in 2027, and $667 million in 2028. We anticipate funding capital expenditures through cash flows from operations, available credit sources, debt issuances and future rate increases. In order to fund South Dakota generation investment equity issuances are expected beginning in 2027. The actual amount of capital

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expenditures is subject to certain factors including the impact that a material change in operations, available financing, supply chain issues, or inflation could impact our current liquidity and ability to fund capital resource requirements. Events such as these could cause us to defer a portion of our planned capital expenditures, as necessary. To fund our strategic growth opportunities, we evaluate the additional capital need in balance with debt capacity and equity issuances that would be intended to allow us to maintain investment grade ratings.

Short-term Borrowings

For further information on our short-term borrowings, see Note 12 - Short-Term Borrowings and Credit Arrangements to the Consolidated Financial Statements included herein. NorthWestern Energy Group has $150.0 million of short-term borrowings maturing in 2026, which we intend to refinance.

Credit Facilities

Liquidity is generally provided by internal operating cash flows and the use of our unsecured revolving credit facilities. We utilize availability under our revolving credit facilities to manage our cash flows due to the seasonality of our business and to fund capital investment. Cash on hand in excess of current operating requirements is generally used to invest in our business and reduce borrowings.

For further information on our credit facilities, see Note 12 - Short-Term Borrowings and Credit Arrangements to the Consolidated Financial Statements included herein.

The following table presents additional information about borrowings under our revolving credit facilities during the year ended December 31, 2025 (in millions):

Amount outstanding at year end$404.0
Daily average amount outstanding$291.0
Maximum amount outstanding$415.0
Minimum amount outstanding$36.0

As of February 6, 2026, availability under our revolving credit facilities was approximately $229.0 million, and there were no letters of credit outstanding.

Long-term Debt and Equity

We generally issue long-term debt to refinance other long-term debt maturities and borrowings under our revolving credit facilities, as well as to fund long-term capital investments and strategic opportunities. We have $105.0 million of long-term debt maturing in 2026, which we intend to refinance.

For further information on our long-term debt, see Note 13 - Long-Term Debt and Finance Leases to the Consolidated Financial Statements included herein.

We generally issue equity securities to fund long-term investment in our business. We evaluate our equity issuance needs to support our plan to maintain a 50 - 55 percent debt to total capital ratio excluding finance leases.

For further information regarding equity, see Note 18 - Common Stock to the Consolidated Financial Statements included herein.

Credit Ratings

In general, less favorable credit ratings make debt financing more costly and more difficult to obtain on terms that are favorable to us and our customers, may impact our trade credit availability, and could result in the need to issue additional equity securities. Fitch Ratings (Fitch), Moody's Investors Service (Moody's), and S&P Global Ratings (S&P) are independent credit-rating agencies that rate our debt securities. These ratings indicate the agencies’ assessment of our ability to pay interest and principal when due on our debt. As of February 6, 2026, our current ratings with these agencies are as follows:

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Issuer RatingSenior Secured RatingSenior Unsecured RatingOutlook
NorthWestern Energy Group
Fitch(1)BBB-BBBStable
Moody’s----
S&PBBB--Positive
NW Corp
Fitch(1)BBBA-BBB+Stable
Moody’sBaa2A3Baa2Stable
S&PBBBA--Positive
NWE Public Service
Fitch(1)BBBA-BBB+Stable
Moody’sBaa2A3-Stable
S&PBBBA--Stable

(1) This Fitch Issuer Rating represents the Issuer Default Rating.

A security rating is not a recommendation to buy, sell or hold securities. Such rating may be subject to revision or withdrawal at any time by the credit rating agency and each rating should be evaluated independently of any other rating.

Contractual Obligations and Other Commitments

We have a variety of contractual obligations and other commitments that require payment of cash at certain specified periods. With the exception of maturities of long-term debt, we anticipate funding these obligations through cash flows from operations. The following table summarizes our contractual cash obligations and commitments as of December 31, 2025. See additional discussion in Note 20 - Commitments and Contingencies to the Consolidated Financial Statements.

Total20262027202820292030Thereafter
(in thousands)
Long-term debt(1)$3,298,660$105,000$$583,660$33,000$650,000$1,927,000
Finance leases1,8651,865
Short-term borrowings150,000150,000
Estimated pension and other postretirement obligations(2)51,06712,64310,2069,8069,3069,106N/A
QF liability(3)168,59255,39356,66542,40014,134
Supply and capacity contracts(4)3,883,865424,471343,663340,135341,470316,6672,117,459
Contractual interest payments on debt(5)1,515,754142,813137,144140,276109,17296,182890,167
Commitments for significant capital projects(6)51,11151,111$
Total Commitments(7)$9,120,914$943,296$547,678$1,116,277$507,082$1,071,955$4,934,626

(1) Represents cash payments for long-term debt and excludes $12.7 million of debt discounts and debt issuance costs, net.

(2) We have estimated cash obligations related to our pension and other postretirement benefit programs for five years, as it is not practicable to estimate thereafter. The pension and other postretirement benefit estimates reflect our expected cash contributions, which may be in excess of minimum funding requirements.

(3) Certain QFs require us to purchase minimum amounts of energy at prices ranging from $124 to $130 per MWH through 2029. Our estimated gross contractual obligation related to these QFs is approximately $168.6 million. A portion of the costs incurred to purchase this energy is recoverable through rates authorized by the MPSC, totaling approximately $152.8 million.

(4) We have entered into various purchase commitments, largely purchased power, electric transmission, coal and natural gas supply and natural gas transportation contracts (exclusive of the qualifying facilities liability discussed above). These commitments range from one to 24 years.

The majority of our energy supply costs incurred under these contracts are recoverable through rate mechanisms, as further described in Note 6 - Regulatory Assets and Liabilities.

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(5) Contractual interest payments include our revolving credit facilities, which have a variable interest rate. We have assumed an average interest rate of 5.07 percent on the outstanding balance through maturity of the credit facilities.

(6) Represents significant firm purchase commitments for construction of planned capital projects.

(7) The table above excludes potential tax payments related to unrecognized tax benefits as they are not practicable to estimate. Additionally, the table above excludes reserves for environmental remediation (See Note 20 - Commitments and Contingencies) and AROs (see Note 8 - Asset Retirement Obligations) as the amount and timing of cash payments may be uncertain.

Other Obligations - As a co-owner of Colstrip, we provided surety bonds of approximately $13.5 million and $15.8 million as of December 31, 2025 and 2024, respectively, to ensure the operation and maintenance of remedial and closure actions are carried out related to the Administrative Order on Consent Regarding Impacts Related to Wastewater Facilities Comprising the Closed-Loop System at Colstrip Steam Electric Stations, Colstrip Montana (the AOC) as required by the MDEQ. As costs are incurred under the AOC, the surety bonds will be reduced.

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CRITICAL ACCOUNTING ESTIMATES

Management's discussion and analysis of financial condition and results of operations is based on our Consolidated Financial Statements, which have been prepared in accordance with GAAP. The preparation of these Consolidated Financial Statements requires us to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses, and related disclosure of contingent assets and liabilities. We base our estimates on historical experience and other assumptions that are believed to be proper and reasonable under the circumstances. We continually evaluate the appropriateness of our estimates and assumptions. Actual results could differ from those estimates.

We have identified the policies and related procedures below that contain accounting estimates that involve a significant level of estimation uncertainty and have had or are reasonably likely to have a material impact on our financial condition or results of operations.

Regulatory Assets and Liabilities

Our operations are subject to the provisions of ASC 980, Regulated Operations (ASC 980). Our regulatory assets are the probable future revenues associated with certain costs to be recovered from customers through the ratemaking process, including our estimate of amounts recoverable for natural gas and electric supply purchases. Regulatory liabilities are the probable future reductions in revenues associated with amounts to be credited to customers through the ratemaking process. We determine which costs are recoverable by consulting previous rulings by state regulatory authorities in jurisdictions where we operate or other factors that lead us to believe that cost recovery is probable. This accounting treatment is impacted by the uncertainties of our regulatory environment, anticipated future regulatory decisions and their impact. If any part of our operations becomes no longer subject to the provisions of ASC 980, or facts and circumstances lead us to conclude that a recorded regulatory asset is no longer probable of recovery, we would record a charge to earnings, which could be material. In addition, we would need to determine if there was any impairment to the carrying costs of the associated plant and inventory assets.

While we believe that our assumptions regarding future regulatory actions are reasonable, different assumptions could materially affect our results. See Note 6 - Regulatory Assets and Liabilities to the Consolidated Financial Statements for further discussion.

Pension and Postretirement Benefit Plans

We sponsor and/or contribute to pension, postretirement health care and life insurance benefits for eligible employees. Our reported costs of providing pension and other postretirement benefits, as described in Note 16 - Employee Benefit Plans to the Consolidated Financial Statements, are dependent upon numerous factors including the provisions of the plans, changing employee demographics, rate of return on plan assets and other economic conditions, and various actuarial calculations, assumptions, and accounting mechanisms. As a result of these factors, significant portions of pension and other postretirement benefit costs recorded in any period do not reflect (and are generally greater than) the actual benefits provided to plan participants. Due to the complexity of these calculations, the long-term nature of the obligations, and the importance of the assumptions utilized, the determination of these costs is considered a critical accounting estimate.

Assumptions

Key actuarial assumptions utilized in determining these costs include:

•Discount rates used in determining the future benefit obligations;

•Expected long-term rate of return on plan assets; and

•Mortality assumptions.

We review these assumptions on an annual basis and adjust them as necessary. The assumptions are based upon market interest rates, past experience and management's best estimate of future economic conditions.

We set the discount rate using a yield curve analysis, which projects benefit cash flows into the future and then discounts those cash flows to the measurement date using a yield curve. This is done by constructing a hypothetical bond portfolio whose cash flow from coupons and maturities matches the year-by-year projected benefit cash flow from our plans. Based on this analysis as of December 31, 2025, our discount rate for both NorthWestern Energy SD/NE Pension Plan and NorthWestern Energy MT Pension Plan is 5.20 percent and 5.65 percent, respectively.

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In determining the expected long-term rate of return on plan assets, we review historical returns, the future expectations for returns for each asset class weighted by the target asset allocation of the pension and postretirement portfolios, and long-term inflation assumptions. Our expected long-term rate of return on assets assumptions are 4.96% percent and 6.3% percent on the NorthWestern Energy SD/NE Pension Plan and NorthWestern Energy MT Pension Plan, respectively, for 2026.

Cost Sensitivity

The following table reflects the sensitivity of pension costs to changes in certain actuarial assumptions (in thousands):

Actuarial AssumptionChange in AssumptionImpact on Pension CostImpact on Projected Benefit Obligation
Discount rate increase0.25%$127$(6,446)
Discount rate decrease(0.25)%256,787
Rate of return on plan assets increase0.25%(798)N/A
Rate of return on plan assets decrease(0.25)%798N/A

Accounting Treatment

We recognize the funded status of each plan as an asset or liability in the Consolidated Balance Sheets. Differences between actuarial assumptions and actual plan results are deferred and are recognized into earnings only when the accumulated differences exceed 10 percent of the greater of the projected benefit obligation or the market-related value of plan assets, which reduces the volatility of reported pension costs. If necessary, the excess is amortized over the average remaining service period of active employees.

Due to the various regulatory treatments of the plans, our Consolidated Financial Statements reflect the effects of the different rate making principles followed by the jurisdictions regulating us. Pension costs in Montana and other postretirement benefit costs in South Dakota are included in rates on a pay as you go basis for regulatory purposes. Pension costs in South Dakota and other postretirement benefit costs in Montana are included in rates on an accrual basis for regulatory purposes. Regulatory assets have been recognized for the obligations that will be included in future cost of service.

Income Taxes

Judgment and the use of estimates are required in developing the provision for income taxes and reporting of tax-related assets and liabilities. Deferred income tax assets and liabilities represent the future effects on income taxes from temporary differences between the bases of assets and liabilities for financial reporting and tax purposes. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to reverse. The probability of realizing deferred tax assets is based on forecasts of future taxable income and the availability of tax planning strategies that can be implemented, if necessary, to realize deferred tax assets. We establish a valuation allowance when it is more likely than not that all, or a portion of, a deferred tax asset will not be realized. Exposures exist related to various tax filing positions, which may require an extended period of time to resolve and may result in income tax adjustments by taxing authorities. We have reduced deferred tax assets or established liabilities based on our best estimate of future probable adjustments related to these exposures. On a quarterly basis, we evaluate exposures in light of any additional information and make adjustments as necessary to reflect the best estimate of the future outcomes. We believe our deferred tax assets and established liabilities are appropriate for estimated exposures; however, actual results may differ significantly from these estimates.

The interpretation of tax laws involves uncertainty. Ultimate resolution of income tax matters may result in favorable or unfavorable impacts to net income and cash flows and adjustments to tax-related assets and liabilities could be material. The uncertainty and judgment involved in the determination and filing of income taxes is accounted for by prescribing a minimum recognition threshold that a tax position is required to meet before being recognized in the Consolidated Financial Statements. We recognize tax positions that meet the more-likely-than-not threshold as the largest amount of tax benefit that is greater than 50 percent likely of being realized upon ultimate settlement with a taxing authority that has full knowledge of all relevant information. As of December 31, 2025, we have not recorded any unrecognized tax benefits. The resolution of tax matters in a particular future period could have a material impact on our provision for income taxes, results of operations and our cash flows. See Note 14 - Income Taxes to the Consolidated Financial Statements for further discussion.

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NEW ACCOUNTING STANDARDS

See Note 2 - Significant Accounting Policies, to the Consolidated Financial Statements, included in Item 8 herein for a discussion of new accounting standards.

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MD&A history

Prior-year 10-K MD&A spans are extracted from SEC filings with the same bounded parser used for the latest filing. The latest 10-K appears above; prior years are below.

FY 2024 10-K MD&A

SEC filing source: 0001993004-25-000021.

Extracted structurally from real Item 7 body heading to real Item 7A/8 boundary. Confidence: high. Filing date: 2025-02-13. Report date: 2024-12-31.

ITEM 7. MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

The following includes a discussion of our results of operations and cash flows for the year ended December 31, 2024 compared to the year ended December 31, 2023, on both a consolidated basis and on a segment basis. For a discussion of our financial results and cash flows for the year ended December 31, 2023 compared with the year ended December 31, 2022, see Management's Discussion and Analysis of Financial Condition and Results of Operations in our Annual Report on Form 10-K for the year ended December 31, 2023.

This discussion should be read in conjunction with our Consolidated Financial Statements and related notes contained elsewhere in this Annual Report on Form 10-K. For additional information related to our segments, see Note 20 - Segment and Related Information, to the Consolidated Financial Statements.

Non-GAAP Financial Measure

The following discussion includes financial information prepared in accordance with GAAP, as well as another financial measure, Utility Margin, that is considered a “non-GAAP financial measure.” Generally, a non-GAAP financial measure is a numerical measure of a company’s financial performance, financial position or cash flows that excludes (or includes) amounts that are included in (or excluded from) the most directly comparable measure calculated and presented in accordance with GAAP. We define Utility Margin as Operating Revenues less fuel, purchased supply and direct transmission expense (exclusive of depreciation and depletion) as presented in our Consolidated Statements of Income. This measure differs from the GAAP definition of Gross Margin due to the exclusion of Operating and maintenance, Property and other taxes, and Depreciation and depletion expenses, which are presented separately in our Consolidated Statements of Income. The following discussion includes a reconciliation of Utility Margin to Gross Margin, the most directly comparable GAAP measure.

We believe that Utility Margin provides a useful measure for investors and other financial statement users to analyze our financial performance in that it excludes the effect on total revenues caused by volatility in energy costs and associated regulatory mechanisms. This information is intended to enhance an investor's overall understanding of results. Under our various state regulatory mechanisms, as detailed below, our supply costs are generally collected from customers. In addition, Utility Margin is used by us to determine whether we are collecting the appropriate amount of energy costs from customers to allow for recovery of operating costs, as well as to analyze how changes in loads (due to weather, economic or other conditions), rates and other factors impact our results of operations. Our Utility Margin measure may not be comparable to that of other companies' presentations or more useful than the GAAP information provided elsewhere in this report.

OVERVIEW

NorthWestern Energy Group, doing business as NorthWestern Energy, provides electricity and/or natural gas to approximately 787,000 customers in Montana, South Dakota, Nebraska, and Yellowstone National Park. Our operations in Montana and Yellowstone National Park are conducted through our subsidiary, NW Corp, and our operations in South Dakota and Nebraska are conducted through our subsidiary, NWE Public Service. As you read this discussion and analysis, refer to our Consolidated Statements of Income, which present the results of our operations for 2024, 2023 and 2022. Following is a discussion of our strategy and significant trends.

We work to deliver safe, reliable and innovative energy solutions that create value for customers, communities, employees and investors. We do this by providing low-cost and reliable service performed by highly-adaptable and skilled employees. We are focused on delivering long-term shareholder value through:

•Infrastructure investment focused on a stronger and smarter grid to improve the customer experience, while enhancing grid reliability and safety. This includes automation in customer meters, distribution and substations that enables the use of proven new technologies.

•Investing in and integrating supply resources that balance reliability, cost, capacity, and sustainability considerations with more predictable long-term commodity prices.

•Continually improving our operating efficiency. Financial discipline is essential to earning our authorized return on invested capital and maintaining a strong balance sheet, stable cash flows, and quality credit ratings to continue to attract cost-effective capital for future investment.

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We expect to pursue these investment opportunities and manage our business in a manner that allows us to be flexible in adjusting to changing economic conditions by adjusting the timing and scale of the projects.

In 2024, approximately 58 percent of our owned and long-term contracted resources originated from carbon-free resources, compared to approximately 41 percent for the total U.S. electric power industry. We are committed to providing customers with reliable and affordable electric and natural gas services while also being good stewards of the environment. Towards this end, our efforts towards a carbon-free future are outlined through our goal to achieve net zero carbon emissions by 2050. Our vision for the future builds on the progress we have made, including our hydroelectric system in Montana, which is 100 percent carbon free and is readily available capacity. For us, wind generation is a close second and continues to grow. While utility-scale solar energy has not been a significant portion of our energy mix to date, we recently entered into power purchase agreements with two solar projects totaling 160-megawatts that began delivering energy to our Montana customers in 2023. We expect solar to further evolve along with advances in energy storage. We are committed to working with our customers and communities to help them achieve their sustainability goals and add new technology on our system.

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HOW WE PERFORMED IN 2024 COMPARED TO OUR 2023 RESULTS

Year Ended December 31, 2024 vs. 2023
Income Before Income TaxesIncome Tax Benefit (Expense)Net Income
(in millions)
December 31, 2023$201.6$(7.5)$194.1
Variance in revenue and fuel, purchased supply, and direct transmission expense(1) items impacting net income:
Base rates62.4(15.8)46.6
Electric transmission revenue18.6(4.7)13.9
Montana interim rates (subject to refund)4.8(1.2)3.6
Montana natural gas transportation2.3(0.6)1.7
Montana property tax tracker collections1.1(0.3)0.8
Production tax credits, offset within income tax benefit (expense)0.2(0.2)
Non-recoverable Montana electric supply costs(7.9)2.0(5.9)
QF liability adjustment(4.2)1.1(3.1)
Natural gas retail volumes(4.0)1.0(3.0)
Electric retail volumes(0.9)0.2(0.7)
Other(3.2)0.8(2.4)
Variance in expense items(2) impacting net income:
Operating, maintenance, and administrative(19.4)4.9(14.5)
Depreciation(17.1)4.3(12.8)
Interest expense(17.1)4.3(12.8)
Property and other taxes not recoverable within trackers(4.4)1.1(3.3)
Release of unrecognized tax benefits (inclusive of related interest previously accrued)17.817.8
Gas repairs safe harbor method change7.07.0
Other1.9(4.8)(2.9)
December 31, 2024$214.7$9.4$224.1
Change in Net Income$30.0

(1) Exclusive of depreciation and depletion shown separately below.

(2) Excluding fuel, purchased supply, and direct transmission expense.

Consolidated net income in 2024 was $224.1 million as compared with $194.1 million in 2023. This increase was primarily due to new base rates in Montana and South Dakota, electric transmission revenue, and income tax benefits from a change to the gas repairs safe harbor method and a reduction to our unrecognized tax benefits. These were offset in part by non-recoverable Montana electric supply costs, a less favorable QF liability adjustment, electric and natural gas retail volumes, depreciation, operating, administrative and general costs, and interest expense.

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SIGNIFICANT TRENDS AND REGULATION

Regulatory Update

Rate reviews are necessary to recover the cost of providing safe, reliable service, while contributing to earnings growth and achieving our financial objectives. We regularly review the need for electric and natural gas rate relief in each state in which we provide service. Our ongoing rate review activity includes the following:

Montana Rate Review - In July 2024, we filed a Montana electric and natural gas rate review (2023 test year) with the MPSC. The filing requests a base rate annual revenue increase of $156.5 million ($69.4 million net with Property Tax and PCCAM tracker adjustments) for electric and $28.6 million for natural gas. Our request is based on a return on equity of 10.80 percent with a capital structure including 46.81 percent equity, and forecasted 2024 electric and natural gas rate base of $3.45 billion and $731.9 million, respectively. The electric rate base investment includes the 175-megawatt natural gas-fired Yellowstone County Generating Station, which was placed in service in October 2024.

In November 2024, the MPSC partially approved our requested interim rates, which are subject to refund, increasing electric and natural gas base rates by $18.4 million and $17.4 million, respectively, and decreasing our PCCAM base costs by $88.0 million, effective December 1, 2024.

In January 2025, intervenor testimony was filed and we anticipate filing our rebuttal testimony in March 2025. Based on the procedural schedule developed by the MPSC, a hearing on our rate review request is scheduled to commence on April 22, 2025. If a final order is not received by May 23, 2025, which is 270 days from acceptance of our filing, we intend to implement our requested rates as permitted by the MPSC regulations, which will be subject to refund until a final order is received.

South Dakota Natural Gas Rate Review - In June 2024, we filed a natural gas rate review (2023 test year) with the SDPUC for an annual increase to natural gas rates totaling approximately $6.0 million. Our request was based on a rate of return of 7.75 percent and rate base of $95.6 million. In December 2024, the SDPUC issued a final order approving the settlement agreement between NorthWestern and SDPUC Staff for an annual increase in base rates of approximately $4.6 million and an authorized rate of return of 6.91 percent. The approved settlement is based on a rate base of $96.2 million. Final rates were effective December 19, 2024.

Nebraska Natural Gas Rate Review - In June 2024, we filed a natural gas rate review (2023 test year) with the NPSC. The filing requests a base rate annual revenue increase of $3.6 million. Our request is based on a return on equity of 10.70 percent, a capital structure including 53.13 percent equity, and rate base of $47.4 million. Interim rates, which increased base natural gas rates $2.3 million, were implemented on October 1, 2024. Interim rates will remain in effect on a refundable basis until the NPSC issues a final order.

Electric Resource Planning - Montana

Yellowstone County 175 MW plant - Construction of the generation facility was substantially completed and the plant placed in service in October 2024. As of December 31, 2024, we have incurred $305.5 million of generation plant costs and $12.1 million of non-generation plant costs related to YCGS. The lawsuit challenging the YCGS air quality permit, which required us to suspend construction activities for a period of time, as well as additional related legal and construction challenges, delayed the project timing and increased costs. On January 3, 2025, the Montana Supreme Court ordered that the YCGS air quality permit be reinstated. See Note 18 - Commitments and Contingencies to the Consolidated Financial Statements included herein for additional information regarding legal challenges impacting YCGS.

Acquisition of Colstrip Interests - As previously disclosed, in January 2023 and in July 2024, we entered into definitive agreements, the first with Avista Corporation (Avista) and the second with Puget Sound Energy (Puget), to acquire their respective interests in Colstrip Units 3 & 4 for $0. In particular, we agreed to acquire a 15% (222 megawatts) interest from Avista and a 25% (370 megawatts) interest from Puget. These agreements are substantially similar and are both scheduled to close December 31, 2025, subject to the satisfaction of customary closing conditions and approvals contained within the agreements. Under the terms of the agreements, we will be responsible for operating costs starting on January 1, 2026; while Puget and Avista will remain responsible for their respective pre-closing share of environmental and pension liabilities attributed to events or conditions existing prior to the closing of the transaction and for any future decommission and demolition costs associated with the existing facilities that comprise their interests.

Acquisition of Avista and Puget's interests would result in our ownership of 55 percent of the facility with the ability to guide operating and maintenance investments. This would provide capacity to help us meet our obligation to provide reliable and cost effective power to our customers in Montana, while allowing opportunity for us to identify and plan for newer lower or no-carbon technologies in the future.

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EPA Rules

In April 2024, the EPA released GHG Rules for existing coal-fired facilities and new coal and natural gas-fired facilities as well as MATS Rules. Compliance with the rules will require expensive upgrades at Colstrip Units 3 and 4 with proposed compliance dates that may not be achievable and / or require technology that is unproven, resulting in significant impacts to costs of the facilities. The final MATS and GHG Rules require compliance as early as 2027 and 2032, respectively. However, the Trump Administration is evaluating energy related regulations impacting reliability and affordability. See Note 18 - Commitments and Contingencies to the Consolidated Financial Statements included herein for additional information regarding these rules.

Acquisition of Energy West Montana Assets

In July 2024, we entered into an Asset Purchase Agreement with Hope Utilities to acquire its Energy West natural gas utility distribution system and operations serving approximately 33,000 customers located near Great Falls, Cut Bank, and West Yellowstone, Montana for approximately $39.0 million, subject to certain working capital and other agreed upon closing adjustments. The transaction is subject to a number of customary closing conditions, including MPSC approval, and we expect the acquisition to be completed in the first half of 2025.

Regional Transmission Development Activities

In August 2024, the U.S. Department of Energy awarded a $700.0 million grant through the Grid Resilience and Innovation Partnership (GRIP) program to advance the NPC Consortium project. The 415-mile, high-voltage direct-current transmission line is intended to connect Montana's Colstrip substation, of which we are the operator and a joint owner, to central North Dakota, bridging the eastern and western U.S. energy grids. The NPC Consortium includes potential upgrades to our jointly owned Colstrip Transmission System and $70.0 million of the award is earmarked for the Colstrip Transmission System Upgrade. The NPC project, estimated to be a $3.6 billion investment, aims to enhance grid reliability, support renewable energy integration, and provide additional capacity across multiple states. We collaborated with Grid United, the Montana Department of Commerce, and other regional utilities on the successful GRIP grant application.

In addition to the Colstrip Transmission System Upgrade, in December 2024, we signed a nonbinding memorandum of understanding (MOU) with North Plains Connector LLC, a wholly owned subsidiary of Grid United, to own 10 percent (300 megawatts) of the NPC Consortium project. The project is entering the permitting phase and initiating regulatory filings with approvals targeted in 2026. Construction is expected to commence in 2028, with the project expected to be operational by 2032. Under the terms of the MOU, Grid United will continue to fund the development of the NPC and we will invest when the regulatory approvals and permits are in place. The project is a critical infrastructure investment that aligns with our commitment to providing reliable and affordable energy to our customers while also supporting broader grid resilience efforts in the region.

President Trump issued an Executive Order on January 20, 2025, "Unleashing American Energy," directing all federal executive agency heads to review all agency actions implicating energy reliability and affordability or potentially burdening the development of domestic energy resources. This Executive Order has delayed, for up to 90 days, the disbursement of the funds granted by the U.S. Department of Energy for the NPC Consortium project.

We have also entered into a nonbinding letter of intent with Grid United to continue transmission development to further enhance the grid through the southwest corridor of Montana. Development to expand the southwest corridor of Montana through grid build out would represent a significant step in enhancing connectivity between Montana and the broader Western energy market - bolstering grid reliability, allowing for critical import capability, and enabling customers to access and benefit from emerging energy markets in the West.

Montana Data Centers

In December 2024, we announced two separate nonbinding letters of intent to provide electric supply services for data centers being developed in Montana. The combined energy service requirement is expected to be 75 megawatts beginning in early 2026 with growth of up to 400 megawatts or more by 2030. Our strategic acquisition of additional interest in Colstrip Units 3 & 4 beginning in 2026, the construction of the YCGS, and our balanced energy portfolio have enabled us to serve new large energy supply customers while continuing to provide our current customers with affordable and reliable energy.

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SIGNIFICANT INFRASTRUCTURE INVESTMENTS AND INITIATIVES

Our estimated capital expenditures for the next five years, including our electric and natural gas transmission and distribution and electric generation infrastructure investment plan, are as follows (in millions):

Electric Supply Resource Plans - Our energy resource plans identify portfolio resource requirements including potential investments. For additional information related to our electric supply resource plans, see Item 1. Business, where we discuss electric resource planning for our Montana and South Dakota jurisdictions.

Distribution and Transmission Modernization and Maintenance - The primary goals of our infrastructure investments are to reverse the trend in aging infrastructure, maintain reliability, proactively manage safety, build capacity into the system, and prepare our network for the adoption of new technologies. We are taking a proactive and pragmatic approach to replacing these assets while also evaluating the implementation of additional technologies to prepare the overall system for smart grid applications. Over $2.2 billion or 82 percent of our capital forecast above is projected to be spent on our distribution and transmission system. Beginning in 2021, we began installing automated metering infrastructure in Montana. We expect this project to be substantially complete in 2025, with a total cost of approximately $105.0 million, of which approximately $10.0 million remains and is reflected in the five year capital forecast above.

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RESULTS OF OPERATIONS

Our consolidated results include the results of our divisions and subsidiaries constituting each of our business segments. The overall consolidated discussion is followed by a detailed discussion of utility margin by segment.

Factors Affecting Results of Operations

Our revenues may fluctuate substantially with changes in supply costs, which are generally collected in rates from customers. In addition, various regulatory agencies approve the prices for electric and natural gas utility service within their respective jurisdictions and regulate our ability to recover costs from customers.

Revenues are also impacted by customer growth and usage, the latter of which is primarily affected by weather and the impact of energy efficiency initiatives and investment. Very cold winters increase demand for natural gas and to a lesser extent, electricity, while warmer than normal summers increase demand for electricity, especially among our residential customers. We measure this effect using degree-days, which is the difference between the average daily actual temperature and a baseline temperature of 65 degrees. Heating degree-days result when the average daily temperature is less than the baseline. Cooling degree-days result when the average daily temperature is greater than the baseline. The statistical weather information in our regulated segments represents a comparison of this data.

Fuel, purchased supply and direct transmission expenses are costs directly associated with the generation and procurement of electricity and natural gas. These costs are generally collected in rates from customers and may fluctuate substantially with market prices and customer usage.

Operating and maintenance expenses are costs associated with the ongoing operation of our vertically-integrated utility facilities which provide electric and natural gas utility products and services to our customers. Among the most significant of these costs are those associated with direct labor and supervision, repair and maintenance expenses, and contract services. These costs are normally fairly stable across broad volume ranges and therefore do not normally increase or decrease significantly in the short term with increases or decreases in volumes.

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OVERALL CONSOLIDATED RESULTS

Year Ended December 31, 2024 Compared with Year Ended December 31, 2023

Consolidated net income in 2024 was $224.1 million as compared with $194.1 million in 2023, an increase of $30.0 million. This increase was primarily due to new base rates in Montana and South Dakota, electric transmission revenue, and income tax benefits related to the gas repairs safe harbor method and a reduction in our unrecognized tax benefits. These were offset in part by non-recoverable Montana electric supply costs, a less favorable QF liability adjustment, electric and natural gas retail volumes, depreciation, operating, administrative and general costs, and interest expense.

Consolidated gross margin in 2024 was $460.8 million as compared with $416.3 million in 2023, an increase of $44.5 million or 10.7 percent. This increase was primarily due to new base rates in Montana and South Dakota, electric transmission revenue, Montana interim rates, subject to refund, and Montana property tax tracker collections. These were offset in party by non-recoverable Montana electric supply costs, a less favorable QF liability adjustment, electric and natural gas retail volumes, and depreciation.

ElectricNatural GasTotal
202420232024202320242023
(in millions)
Reconciliation of gross margin to utility margin:
Operating Revenues$1,200.7$1,068.8$313.2$353.3$1,513.9$1,422.1
Less: Fuel, purchased supply and direct transmission expense (exclusive of depreciation and depletion shown separately below)329.6262.7104.2157.5433.8420.2
Less: Operating and maintenance171.7166.056.154.5227.8220.5
Less: Property and other taxes126.5120.337.434.3163.9154.6
Less: Depreciation and depletion190.0174.137.636.4227.6210.5
Gross Margin382.9345.777.970.6460.8416.3
Operating and maintenance171.7166.056.154.5227.8220.5
Property and other taxes126.5120.337.434.3163.9154.6
Depreciation and depletion190.0174.137.636.4227.6210.5
Utility Margin(1)$871.1$806.1$209.0$195.8$1,080.1$1,001.9

(1) Non-GAAP financial measure. See "Non-GAAP Financial Measure" above.

Year Ended December 31,
20242023Change% Change
(in millions)
Utility Margin
Electric$871.1$806.1$65.08.1%
Natural Gas209.0195.813.26.7
Total Utility Margin(1)$1,080.1$1,001.9$78.27.8%

(1) Non-GAAP financial measure. See "Non-GAAP Financial Measure" above.

Consolidated utility margin in 2024 was $1,080.1 million as compared with $1,001.9 million in 2023, an increase of $78.2 million, or 7.8 percent.

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Primary components of the change in utility margin include the following (in millions):

Utility Margin2024 vs. 2023
Utility Margin Items Impacting Net Income
Base rates$62.4
Electric transmission revenue due to market conditions and rates18.6
Montana interim rates (subject to refund)4.8
Montana natural gas transportation2.3
Montana property tax tracker collections1.1
Non-recoverable Montana electric supply costs(7.9)
QF liability adjustment(4.2)
Natural gas retail volumes(4.0)
Electric retail volumes(0.9)
Other(3.0)
Change in Utility Margin Impacting Net Income69.2
Utility Margin Items Offset Within Net Income
Property and other taxes recovered in revenue, offset in property and other taxes6.4
Operating expenses recovered in revenue, offset in operating and maintenance expense2.4
Production tax credits, offset in income tax expense0.2
Change in Items Offset Within Net Income9.0
Increase in Consolidated Utility Margin(1)$78.2

(1) Non-GAAP financial measure. See "Non-GAAP Financial Measure" above.

Lower electric residential and commercial retail volumes were driven by unfavorable weather in South Dakota impacting residential demand and lower commercial demand in all jurisdictions as compared to the prior year, partly offset by higher industrial demand and customer growth. Lower natural gas retail volumes were driven by unfavorable weather in all jurisdictions partly offset by customer growth.

Under the PCCAM, net supply costs higher or lower than the PCCAM base rate (PCCAM Base) (excluding qualifying facility (QF) costs) are allocated 90 percent to Montana customers and 10 percent to shareholders. For the twelve months ended December 31, 2024, we under-collected supply costs of $8.0 million resulting in an increase to our under collection of costs, and recorded a decrease in pre-tax earnings of $0.9 million (10 percent of the PCCAM Base cost variance). For the twelve months ended December 31, 2023, we over collected supply costs of $32.9 million resulting in a reduction to our under collection of costs, and recorded an increase in pre-tax earnings of $7.0 million, which was inclusive of a $3.2 million increase in pre-tax earnings related to the retroactive application of higher PCCAM Base rates to July 1, 2022.

The less favorable adjustment to our electric QF liability (unrecoverable costs associated with contracts covered by the Public Utility Regulatory Policies Act of 1978 (PURPA) as part of a 2002 stipulation with the MPSC and other parties) reflects a $0.8 million gain in 2024, as compared with a $5.0 million gain for the same period in 2023, due to a favorable adjustment in the prior year, decreasing the QF liability by $4.2 million, reflecting annual actual contract price escalation for the 2023-2024 contract year, which was less than previously estimated. The 2023-2024 contract year was the last year of the contract that contains variable pricing terms.

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Year Ended December 31,
20242023Change% Change
(in millions)
Operating Expenses (excluding fuel, purchased supply and direct transmission expense)
Operating and maintenance$227.8$220.5$7.33.3%
Administrative and general137.4117.320.117.1
Property and other taxes163.9153.110.87.1
Depreciation and depletion227.6210.517.18.1
Total Operating Expenses (excluding fuel, purchased supply and direct transmission expense)$756.7$701.4$55.37.9%

Consolidated operating expenses, excluding fuel, purchased supply and direct transmission expense, were $756.7 million in 2024, as compared with $701.4 million in 2023. Primary components of the change include the following (in millions):

Operating Expenses
2024 vs. 2023
Operating Expenses (excluding fuel, purchased supply and direct transmission expense) Impacting Net Income
Depreciation expense due to plant additions and higher depreciation rates$17.1
Labor and benefits(1)7.9
Insurance expense, primarily due to increased wildfire risk premiums7.7
Property and other taxes not recoverable within trackers4.4
Litigation outcome (Pacific Northwest Solar)2.4
Electric generation maintenance2.0
Non-cash impairment of alternative energy storage investment1.7
Technology implementation and maintenance1.5
Uncollectible accounts(1.4)
Other(2.3)
Change in Items Impacting Net Income41.0
Operating Expenses Offset Within Net Income
Property and other taxes recovered in trackers, offset in revenue6.4
Pension and other postretirement benefits, offset in other income(1)4.8
Operating and maintenance expenses recovered in trackers, offset in revenue2.4
Deferred compensation, offset in other income0.7
Change in Items Offset Within Net Income14.3
Increase in Operating Expenses (excluding fuel, purchased supply and direct transmission expense)$55.3

(1) In order to present the total change in labor and benefits, we have included the change in the non-service cost component of our pension and other postretirement benefits, which is recorded within other income on our Condensed Consolidated Statements of Income. This change is offset within this table as it does not affect our operating expenses.

Consolidated operating income in 2024 was $323.3 million as compared with $300.5 million in 2023. This increase was primarily due to new base rates in Montana and South Dakota, electric transmission revenue, Montana interim rates, subject to refund, and Montana property tax tracker collections. These were offset in part by non-recoverable Montana electric supply costs, a less favorable QF liability adjustment, electric and natural gas retail volumes, depreciation, operating, and administrative and general costs.

Consolidated interest expense in 2024 was $131.7 million, as compared with $114.6 million in 2023. This increase was due to higher borrowings and interest rates, partly offset by higher capitalization of AFUDC.

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Consolidated other income in 2024 was $23.0 million, as compared with $15.8 million in 2023. This increase was primarily due to a $2.3 million reversal of a previously expensed Community Renewable Energy Project penalty due to a favorable legal ruling, higher capitalization of AFUDC, a decrease in the non-service cost component of pension expense, and an increase in the value of deferred shares held in trust for deferred compensation, offset in part by a $2.5 million non-cash impairment of an alternative energy storage equity investment.

Consolidated income tax benefit in 2024 was $9.4 million, as compared to an income tax expense of $7.5 million in 2023. Our effective tax rate for the twelve months ended December 31, 2024 was (4.4) percent as compared with 3.7 percent for the same period of 2023. As further discussed in Note 12 - Income Taxes, income tax benefit for the twelve months ended December 31, 2024, includes a $21.0 million benefit related to a reduction in our unrecognized tax benefits, inclusive of $4.1 million of previously accrued interest ($16.9 million net of interest). Additionally, during the twelve months ended December 31, 2024, we filed a tax accounting method change with the IRS consistent with the guidance for natural gas transmission and distribution property. This resulted in an income tax benefit of $7.0 million during 2024, related to repair costs that were previously capitalized for tax purposes in the 2022 and prior tax years. Income tax expense for the twelve months ended December 31, 2023, includes a one-time $3.2 million expense for the reduction of previously claimed alternative minimum tax credits as well as a $3.2 million benefit related to a reduction in our unrecognized tax benefits.

We currently estimate our effective tax rate will range between 13.0 percent to 17.0 percent in 2025. Based on the significant NOL income tax position we have, we anticipate paying minimal cash for income taxes into 2028.

The following table summarizes the differences between our effective tax rate and the federal statutory rate (in millions):

Year Ended December 31,
20242023
Income Before Income Taxes$214.7$201.6
Income tax calculated at federal statutory rate45.121.0%42.421.0%
Permanent or flow through adjustments:
State income taxes, net of federal provisions0.40.20.60.3
Flow-through repairs deductions(23.1)(10.8)(25.9)(12.9)
Release of unrecognized tax benefits (2024 is inclusive of $4.1 million of related interest previously accrued)(21.0)(9.8)(3.2)(1.6)
Production tax credits(11.1)(5.2)(10.3)(5.1)
Gas repairs safe harbor method change(7.0)(3.3)
Amortization of excess deferred income taxes(2.9)(1.4)(2.2)(1.1)
Prior year permanent return to accrual adjustments(0.4)(0.2)
Plant and depreciation of flow through items9.44.46.63.3
Unregulated Tax Cuts and Jobs Act excess deferred income taxes(3.4)(1.7)
Reduction to previously claimed alternative minimum tax credit3.21.6
Other, net1.20.7(0.3)(0.1)
(54.5)(25.4)(34.9)(17.3)
Income Tax (Benefit) Expense$(9.4)(4.4)%$7.53.7%

Our effective tax rate typically differs from the federal statutory tax rate primarily due to the regulatory impact of flowing through federal and state tax benefits of repairs deductions, state tax benefit of accelerated tax depreciation deductions (including bonus depreciation when applicable) and production tax credits.

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ELECTRIC OPERATIONS

We have various classifications of electric revenues, defined as follows:

•Retail: Sales of electricity to residential, commercial and industrial customers, and the impact of regulatory mechanisms.

•Regulatory amortization: Primarily represents timing differences for electric supply costs and property taxes between when we incur these costs and when we recover these costs in rates from our customers, which is also reflected in fuel, purchased supply and direct transmission expense and therefore has minimal impact on utility margin. The amortization of these amounts are offset in retail revenue.

•Transmission: Reflects transmission revenues regulated by the FERC.

•Wholesale and other are largely utility margin neutral as they are offset by changes in fuel, purchased supply and direct transmission expense.

Year Ended December 31, 2024 Compared with Year Ended December 31, 2023

RevenuesChangeMWHsAvg. Customer Counts
20242023$%2024202320242023
(in thousands)
Montana$398,790$408,341$(9,551)(2.3)%2,8042,795328,420322,489
South Dakota70,01267,8882,1243.155760351,46751,261
Residential468,802476,229(7,427)(1.6)3,3613,398379,887373,750
Montana408,977431,357(22,380)(5.2)3,1973,23875,87874,438
South Dakota111,813103,1948,6198.41,0931,10113,08412,973
Commercial520,790534,551(13,761)(2.6)4,2904,33988,96287,411
Industrial46,63745,9586791.52,9242,6608079
Other32,81132,756550.21461346,5446,443
Total Retail Electric$1,069,040$1,089,494$(20,454)(1.9)%10,72110,531475,473467,683
Regulatory amortization24,908(105,608)130,516(123.6)
Transmission97,05278,43618,61623.7
Wholesale and Other9,7016,5113,19049.0
Total Revenues$1,200,701$1,068,833$131,86812.3%
Fuel, purchased supply and direct transmission expense(1)329,578262,75566,82325.4
Utility Margin(2)$871,123$806,078$65,0458.1%

(1) Exclusive of depreciation and depletion.

(2) Non-GAAP financial measure. See “Non-GAAP Financial Measure” above. Also see "Overall Consolidated Results" above for reconciliation of gross margin to utility margin.

Cooling Degree Days2024 as compared with:
20242023Historic Average2023Historic Average
Montana48544144810% warmer8% warmer
South Dakota7781,03575225% cooler3% warmer
Heating Degree Days2024 as compared with:
20242023Historic Average2023Historic Average
Montana(1)7,0337,2377,5543% warmer7% warmer
South Dakota6,5017,6657,72415% warmer16% warmer

(1) Montana electric and natural gas heating degree days may differ due to differences in service territory.

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The following summarizes the components of the changes in electric utility margin for the years ended December 31, 2024 and 2023 (in millions):

Utility Margin2024 vs. 2023
Utility Margin Items Impacting Net Income
Base rates$51.0
Electric transmission revenue due to market conditions and rates18.6
Montana interim rates (subject to refund)2.8
Montana property tax tracker collections1.2
Non-recoverable Montana electric supply costs(7.9)
QF liability adjustment(4.2)
Retail volumes(0.9)
Other(0.9)
Change in Utility Margin Items Impacting Net Income59.7
Utility Margin Items Offset Within Net Income
Property and other taxes recovered in revenue, offset in property and other taxes3.4
Operating expenses recovered in revenue, offset in operating and maintenance expense1.7
Production tax credits, offset in income tax expense0.2
Change in Items Offset Within Net Income5.3
Increase in Utility Margin(1)$65.0

(1) Non-GAAP financial measure. See "Non-GAAP Financial Measure" above. Also see "Overall Consolidated Results" above for reconciliation of gross margin to utility margin.

Lower electric residential and commercial retail volumes were driven by unfavorable weather in South Dakota impacting residential demand and lower commercial demand in all jurisdictions as compared to the prior year, partly offset by higher industrial demand and customer growth.

Under the PCCAM, net supply costs higher or lower than the PCCAM base rate (PCCAM Base) (excluding qualifying facility (QF) costs) are allocated 90 percent to Montana customers and 10 percent to shareholders. For the twelve months ended December 31, 2024, we under-collected supply costs of $8.0 million resulting in an increase to our under collection of costs, and recorded a decrease in pre-tax earnings of $0.9 million (10 percent of the PCCAM Base cost variance). For the twelve months ended December 31, 2023, we over collected supply costs of $32.9 million resulting in a reduction to our under collection of costs, and recorded an increase in pre-tax earnings of $7.0 million, which was inclusive of a $3.2 million increase in pre-tax earnings related to the retroactive application of higher PCCAM Base rates to July 1, 2022.

The less favorable adjustment to our electric QF liability (unrecoverable costs associated with contracts covered by the Public Utility Regulatory Policies Act of 1978 (PURPA) as part of a 2002 stipulation with the MPSC and other parties) reflects a $0.8 million gain in 2024, as compared with a $5.0 million gain for the same period in 2023, as further explained above in the consolidated results of operations for the twelve months ended December 31, 2024.

The change in regulatory amortization revenue is due to timing differences between when we incur electric supply costs and when we recover these costs in rates from our customers, which has a minimal impact on utility margin. Our wholesale and other revenues are largely utility margin neutral as they are offset by changes in fuel, purchased supply and direct transmission expenses.

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NATURAL GAS OPERATIONS

We have various classifications of natural gas revenues, defined as follows:

•Retail: Sales of natural gas to residential, commercial and industrial customers, and the impact of regulatory mechanisms.

•Regulatory amortization: Primarily represents timing differences for natural gas supply costs and property taxes between when we incur these costs and when we recover these costs in rates from our customers, which is also reflected in fuel, purchased supply and direct transmission expenses and therefore has minimal impact on utility margin. The amortization of these amounts are offset in retail revenue.

•Wholesale: Primarily represents transportation and storage for others.

Year Ended December 31, 2024 Compared with Year Ended December 31, 2023

RevenuesChangeDekathermsAvg. Customer Counts
20242023$%2024202320242023
(in thousands)
Montana$110,215$136,097(25,882)(19.0)%13,74914,008185,644183,810
South Dakota26,88436,638(9,754)(26.6)2,7093,17942,57742,053
Nebraska21,20535,539(14,334)(40.3)2,2942,58137,95837,793
Residential158,304208,274(49,970)(24.0)18,75219,768266,179263,656
Montana59,92573,721(13,796)(18.7)7,7828,03626,16425,725
South Dakota18,06925,869(7,800)(30.2)2,7913,1697,3837,232
Nebraska11,43222,114(10,682)(48.3)1,6641,9165,0565,023
Commercial89,426121,704(32,278)(26.5)12,23713,12138,60337,980
Industrial1,0411,392(351)(25.2)147157237232
Other1,3521,681(329)(19.6)207209197190
Total Retail Gas$250,123$333,051$(82,928)(24.9)%31,34333,255305,216302,058
Regulatory amortization19,017(25,012)44,029(176.0)
Wholesale and other44,05745,271(1,214)(2.7)
Total Revenues$313,197$353,310$(40,113)(11.4)%
Fuel, purchased supply and direct transmission expense(1)104,238157,507(53,269)(33.8)
Utility Margin(2)$208,959$195,803$13,1566.7%

(1) Exclusive of depreciation and depletion.

(2) Non-GAAP financial measure. See “Non-GAAP Financial Measure” above. Also see "Overall Consolidated Results" above for reconciliation of gross margin to utility margin.

Heating Degree Days2024 as compared with:
20242023Historic Average2023Historic Average
Montana(1)7,2657,4787,7913% warmer7% warmer
South Dakota6,5017,6657,72415% warmer16% warmer
Nebraska5,2415,8936,08511% warmer14% warmer

(1) Montana electric and natural gas heating degree days may differ due to differences in service territory.

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The following summarizes the components of the changes in natural gas utility margin for the years ended December 31, 2024 and 2023 (in millions):

Utility Margin2024 vs. 2023
Utility Margin Items Impacting Net Income
Base rates11.4
Montana natural gas transportation2.3
Montana interim rates (subject to refund)2.0
Retail volumes(4.0)
Montana property tax tracker collections(0.1)
Other(2.1)
Change in Utility Margin Impacting Net Income9.5
Utility Margin Items Offset Within Net Income
Property and other taxes recovered in revenue, offset in property and other taxes3.0
Operating expenses recovered in revenue, offset in operating and maintenance expense0.7
Change in Items Offset Within Net Income3.7
Increase in Utility Margin(1)$13.2

(1) Non-GAAP financial measure. See "Non-GAAP Financial Measure" above. Also see "Overall Consolidated Results" above for reconciliation of gross margin to utility margin.

Lower retail volumes were driven by unfavorable weather in all jurisdictions partly offset by customer growth.

Our wholesale and other revenues are largely utility margin neutral as they are offset by changes in fuel, purchased supply and direct transmission expenses.

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LIQUIDITY AND CAPITAL RESOURCES

Liquidity

We require liquidity to support and grow our business, and use our liquidity for working capital needs, capital expenditures, investments in or acquisitions of assets, and to repay debt. For NorthWestern Energy Group, liquidity is primarily provided through its revolving credit facility and dividends from its utility operating subsidiaries, NW Corp and NWE Public Service. These subsidiaries are subject to certain restrictions that may limit the amount of their dividend distributions. See Note 16 - Common Stock to the Consolidated Financial Statements for more information regarding these dividend restrictions.

We believe our cash flows from operations, existing borrowing capacity, debt and equity issuances and future utility rate increases should be sufficient to fund our operations, service existing debt, pay dividends, and fund capital expenditures. We plan to maintain a 50 - 55 percent debt to total capital ratio excluding finance leases, and expect to continue targeting a long-term dividend payout ratio of 60 - 70 percent of earnings per share; however, there can be no assurance that we will be able to meet these targets.

As of December 31, 2024, our total consolidated net liquidity was approximately $191.3 million, including $4.3 million of cash and $187.0 million of revolving credit facility availability with no letters of credit outstanding.

Cash Flows

The following table summarizes our consolidated cash flows (in millions):

Year Ended December 31,
20242023
Operating Activities
Net income$224.1$194.1
Non-cash adjustments to net income213.5210.1
Changes in working capital(18.9)115.6
Other noncurrent assets and liabilities(11.9)(30.6)
Cash Provided by Operating Activities406.8489.2
Investing Activities
Property, plant and equipment additions(549.3)(566.9)
Other investing activity(5.2)(3.9)
Cash Used in Investing Activities(554.5)(570.8)
Financing Activities
Proceeds from issuance of common stock, net73.6
Issuance of long-term debt215.0300.0
Dividends on common stock(158.6)(154.1)
Line of credit borrowings (repayments), net95.0(132.0)
Financing costs(1.1)(4.3)
Treasury stock activity1.21.1
Cash Provided by Financing Activities151.584.3
Net Increase in Cash, Cash Equivalents, and Restricted Cash$3.8$2.7
Cash, Cash Equivalents, and Restricted Cash, beginning of period$25.2$22.5
Cash, Cash Equivalents, and Restricted Cash, end of period$29.0$25.2

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Operating Activities

As of December 31, 2024, cash, cash equivalents, and restricted cash were $29.0 million as compared with $25.2 million as of December 31, 2023. Cash provided by operating activities totaled $406.8 million for the year ended December 31, 2024 as compared with $489.2 million for the year ended December 31, 2023. As shown in the table below, this decrease in operating cash flows is primarily due to minimal net cash inflows for energy supply costs in the current period due to the timely recovery of energy supply costs compared to significant net cash inflows in 2023 from the recovery of previously under-collected energy supply costs.

Net under-collected supply costs (in millions)
Beginning of yearEnd of yearNet cash inflows
2023$115.4$7.8$107.6
2024$7.8$5.9$1.9
Improvement in annual net cash inflows$(105.7)

Investing Activities

Cash used in investing activities totaled $554.5 million during the year ended December 31, 2024, as compared with $570.8 million during 2023. Plant additions during 2024 include capital maintenance additions of approximately $324.0 million and capacity related capital expenditures of approximately $225.3 million. Plant additions during 2023 included capital maintenance additions of approximately $321.9 million and capacity related capital expenditures of approximately $245.0 million. As discussed above in the “Significant Infrastructure Investments and Initiatives” section, our capital expenditures are forecasted to be $531.0 million in 2024. Additionally, as discussed above in the "Significant Trends and Regulation" section, we anticipate investing $39.0 million for the acquisition of the Energy West Montana Assets in 2025.

Financing Activities

Cash provided by financing activities totaled $151.5 million during the year ended December 31, 2024 as compared with $84.3 million during the year ended December 31, 2023. During the year ended December 31, 2024, cash provided by financing activities reflects proceeds from the issuance of long-term debt of $215.0 million, short-term borrowings of $100.0 million, and net issuances under our revolving lines of credit of $95.0 million, partly offset by payment of dividends of $158.6 million and repayment of 1.00 percent, $100.0 million of Montana First Mortgage Bonds. During the year ended December 31, 2023, cash provided by financing activities reflects net proceeds from the issuance of long-term debt of $300.0 million and proceeds received from the issuance of common stock of $73.6 million, partly offset by payment of dividends of $154.1 million and net repayments under our revolving lines of credit of $132.0 million.

Cash Requirements and Capital Resources

We believe our cash flows from operations, existing borrowing capacity, debt and equity issuances and future rate increases should be sufficient to satisfy our material cash requirements over the short-term and the long-term. As a rate-regulated utility our customer rates are generally structured to recover expected operating costs, with an opportunity to earn a return on our invested capital. This structure supports recovery for many of our operating expenses, although there are situations where the timing of our cash outlays results in increased working capital requirements. Due to the seasonality of our utility business, our short-term working capital requirements typically peak during the coldest winter months and warmest summer months when we cover the lag between when purchasing energy supplies and when customers pay for these costs. Our credit facilities may also be utilized for funding cash requirements during seasonally active construction periods, with peak activity during warmer months. Our cash requirements also include a variety of contractual obligations as outlined below in the “Contractual Obligations and Other Commitments” section.

Our material cash requirements are also related to investment in our business through our capital expenditure program, which is discussed above in the “Significant Infrastructure Investments and Initiatives” section. Our capital expenditures are forecasted to be $531 million in 2025, $549 million in 2026, and $557 million in 2027. We anticipate funding capital expenditures through cash flows from operations, available credit sources, debt issuances and future rate increases. The actual amount of capital expenditures is subject to certain factors including the impact that a material change in operations, available financing, supply chain issues, or inflation could impact our current liquidity and ability to fund capital resource requirements. Events such as these could cause us to defer a portion of our planned capital expenditures, as necessary. To fund our strategic

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growth opportunities, we evaluate the additional capital need in balance with debt capacity and equity issuances that would be intended to allow us to maintain investment grade ratings.

Short-term Borrowings

For further information on our short-term borrowings, see Note 10 - Short-Term Borrowings and Credit Arrangements to the Consolidated Financial Statements included herein. NorthWestern Energy Group has $100.0 million of short-term borrowings maturing in 2025, which we intend to refinance.

Credit Facilities

Liquidity is generally provided by internal operating cash flows and the use of our unsecured revolving credit facilities. We utilize availability under our revolving credit facilities to manage our cash flows due to the seasonality of our business and to fund capital investment. Cash on hand in excess of current operating requirements is generally used to invest in our business and reduce borrowings.

For further information on our credit facilities, see Note 10 - Short-Term Borrowings and Credit Arrangements to the Consolidated Financial Statements included herein.

The following table presents additional information about borrowings under our revolving credit facilities during the year ended December 31, 2024 (in millions):

Amount outstanding at year end$413.0
Daily average amount outstanding$237.1
Maximum amount outstanding$413.0
Minimum amount outstanding$69.0

As of February 7, 2025, availability under our revolving credit facilities was approximately $233.0 million, and there were no letters of credit outstanding.

Long-term Debt and Equity

We generally issue long-term debt to refinance other long-term debt maturities and borrowings under our revolving credit facilities, as well as to fund long-term capital investments and strategic opportunities. We have $300.0 million of long-term debt maturing in 2025, which we intend to refinance.

For further information on our long-term debt, see Note 11 - Long-Term Debt and Finance Leases to the Consolidated Financial Statements included herein.

We generally issue equity securities to fund long-term investment in our business. We evaluate our equity issuance needs to support our plan to maintain a 50 - 55 percent debt to total capital ratio excluding finance leases.

For further information regarding equity, see Note 16 - Common Stock to the Consolidated Financial Statements included herein.

Credit Ratings

In general, less favorable credit ratings make debt financing more costly and more difficult to obtain on terms that are favorable to us and our customers, may impact our trade credit availability, and could result in the need to issue additional equity securities. Fitch Ratings (Fitch), Moody's Investors Service (Moody's), and S&P Global Ratings (S&P) are independent credit-rating agencies that rate our debt securities. These ratings indicate the agencies’ assessment of our ability to pay interest and principal when due on our debt. As of February 7, 2025, our current ratings with these agencies are as follows:

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Issuer RatingSenior Secured RatingSenior Unsecured RatingOutlook
NorthWestern Energy Group
Fitch(1)BBB-BBBStable
Moody’s----
S&PBBB--Stable
NW Corp
Fitch(1)BBBA-BBB+Stable
Moody’sBaa2A3Baa2Stable
S&PBBBA--Stable
NWE Public Service
Fitch(1)BBBA-BBB+Stable
Moody’sBaa2A3-Stable
S&PBBBA--Stable

(1) This Fitch Issuer Rating represents the Issuer Default Rating.

A security rating is not a recommendation to buy, sell or hold securities. Such rating may be subject to revision or withdrawal at any time by the credit rating agency and each rating should be evaluated independently of any other rating.

Contractual Obligations and Other Commitments

We have a variety of contractual obligations and other commitments that require payment of cash at certain specified periods. With the exception of maturities of long-term debt, we anticipate funding these obligations through cash flows from operations. The following table summarizes our contractual cash obligations and commitments as of December 31, 2024. See additional discussion in Note 18 - Commitments and Contingencies to the Consolidated Financial Statements.

Total20252026202720282029Thereafter
(in thousands)
Long-term debt(1)$3,007,660$300,000$105,000$$592,660$33,000$1,977,000
Finance leases5,4613,5961,865
Short-term borrowings100,000100,000
Estimated pension and other postretirement obligations(2)50,31011,3109,7509,7509,7509,750N/A
QF liability(3)228,95260,36055,39356,66542,40014,134
Supply and capacity contracts(4)4,228,637345,821365,202350,381349,347350,2012,467,685
Contractual interest payments on debt(5)1,650,442133,927122,884120,847118,78089,3591,064,645
Commitments for significant capital projects(6)66,83757,9758,862$
Total Commitments(7)$9,338,299$1,012,989$668,956$537,643$1,112,937$496,444$5,509,330

(1) Represents cash payments for long-term debt and excludes $12.4 million of debt discounts and debt issuance costs, net.

(2) We have estimated cash obligations related to our pension and other postretirement benefit programs for five years, as it is not practicable to estimate thereafter. The pension and other postretirement benefit estimates reflect our expected cash contributions, which may be in excess of minimum funding requirements.

(3) Certain QFs require us to purchase minimum amounts of energy at prices ranging from $118 to $130 per MWH through 2029. Our estimated gross contractual obligation related to these QFs is approximately $229.0 million. A portion of the costs incurred to purchase this energy is recoverable through rates authorized by the MPSC, totaling approximately $205.8 million.

(4) We have entered into various purchase commitments, largely purchased power, electric transmission, coal and natural gas supply and natural gas transportation contracts (exclusive of the qualifying facilities liability discussed above). These commitments range from one to 24 years.

The energy supply costs incurred under these contracts are generally recoverable through rate mechanisms approved by the MPSC, as further described in Note 3 - Regulatory Matters.

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(5) Contractual interest payments include our revolving credit facilities, which have a variable interest rate. We have assumed an average interest rate of 5.71 percent on the outstanding balance through maturity of the credit facilities.

(6) Represents significant firm purchase commitments for construction of planned capital projects.

(7) The table above excludes potential tax payments related to unrecognized tax benefits as they are not practicable to estimate. Additionally, the table above excludes reserves for environmental remediation (See Note 18 - Commitments and Contingencies) and AROs (see Note 6 - Asset Retirement Obligations) as the amount and timing of cash payments may be uncertain.

Other Obligations - As a co-owner of Colstrip, we provided surety bonds of approximately $15.8 million and $15.7 million as of December 31, 2024 and 2023, respectively, to ensure the operation and maintenance of remedial and closure actions are carried out related to the Administrative Order on Consent Regarding Impacts Related to Wastewater Facilities Comprising the Closed-Loop System at Colstrip Steam Electric Stations, Colstrip Montana (the AOC) as required by the MDEQ. As costs are incurred under the AOC, the surety bonds will be reduced.

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CRITICAL ACCOUNTING ESTIMATES

Management's discussion and analysis of financial condition and results of operations is based on our Consolidated Financial Statements, which have been prepared in accordance with GAAP. The preparation of these Consolidated Financial Statements requires us to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses, and related disclosure of contingent assets and liabilities. We base our estimates on historical experience and other assumptions that are believed to be proper and reasonable under the circumstances. We continually evaluate the appropriateness of our estimates and assumptions. Actual results could differ from those estimates.

We have identified the policies and related procedures below that contain accounting estimates that involve a significant level of estimation uncertainty and have had or are reasonably likely to have a material impact on our financial condition or results of operations.

Regulatory Assets and Liabilities

Our operations are subject to the provisions of ASC 980, Regulated Operations (ASC 980). Our regulatory assets are the probable future revenues associated with certain costs to be recovered from customers through the ratemaking process, including our estimate of amounts recoverable for natural gas and electric supply purchases. Regulatory liabilities are the probable future reductions in revenues associated with amounts to be credited to customers through the ratemaking process. We determine which costs are recoverable by consulting previous rulings by state regulatory authorities in jurisdictions where we operate or other factors that lead us to believe that cost recovery is probable. This accounting treatment is impacted by the uncertainties of our regulatory environment, anticipated future regulatory decisions and their impact. If any part of our operations becomes no longer subject to the provisions of ASC 980, or facts and circumstances lead us to conclude that a recorded regulatory asset is no longer probable of recovery, we would record a charge to earnings, which could be material. In addition, we would need to determine if there was any impairment to the carrying costs of the associated plant and inventory assets.

While we believe that our assumptions regarding future regulatory actions are reasonable, different assumptions could materially affect our results. See Note 4 - Regulatory Assets and Liabilities to the Consolidated Financial Statements for further discussion.

Pension and Postretirement Benefit Plans

We sponsor and/or contribute to pension, postretirement health care and life insurance benefits for eligible employees. Our reported costs of providing pension and other postretirement benefits, as described in Note 14 - Employee Benefit Plans to the Consolidated Financial Statements, are dependent upon numerous factors including the provisions of the plans, changing employee demographics, rate of return on plan assets and other economic conditions, and various actuarial calculations, assumptions, and accounting mechanisms. As a result of these factors, significant portions of pension and other postretirement benefit costs recorded in any period do not reflect (and are generally greater than) the actual benefits provided to plan participants. Due to the complexity of these calculations, the long-term nature of the obligations, and the importance of the assumptions utilized, the determination of these costs is considered a critical accounting estimate.

Assumptions

Key actuarial assumptions utilized in determining these costs include:

•Discount rates used in determining the future benefit obligations;

•Expected long-term rate of return on plan assets; and

•Mortality assumptions.

We review these assumptions on an annual basis and adjust them as necessary. The assumptions are based upon market interest rates, past experience and management's best estimate of future economic conditions.

We set the discount rate using a yield curve analysis, which projects benefit cash flows into the future and then discounts those cash flows to the measurement date using a yield curve. This is done by constructing a hypothetical bond portfolio whose cash flow from coupons and maturities matches the year-by-year projected benefit cash flow from our plans. Based on this analysis as of December 31, 2024, our discount rate for both NorthWestern Energy SD/NE Pension Plan and NorthWestern Energy MT Pension Plan is 5.50 percent and 5.60 percent, respectively.

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In determining the expected long-term rate of return on plan assets, we review historical returns, the future expectations for returns for each asset class weighted by the target asset allocation of the pension and postretirement portfolios, and long-term inflation assumptions. Our expected long-term rate of return on assets assumptions are 4.58% percent and 6.17% percent on the NorthWestern Energy SD/NE Pension Plan and NorthWestern Energy MT Pension Plan, respectively, for 2025.

Cost Sensitivity

The following table reflects the sensitivity of pension costs to changes in certain actuarial assumptions (in thousands):

Actuarial AssumptionChange in AssumptionImpact on Pension CostImpact on Projected Benefit Obligation
Discount rate increase0.25%$195$(11,443)
Discount rate decrease(0.25)%1,17111,973
Rate of return on plan assets increase0.25%(982)N/A
Rate of return on plan assets decrease(0.25)%982N/A

Accounting Treatment

We recognize the funded status of each plan as an asset or liability in the Consolidated Balance Sheets. Differences between actuarial assumptions and actual plan results are deferred and are recognized into earnings only when the accumulated differences exceed 10 percent of the greater of the projected benefit obligation or the market-related value of plan assets, which reduces the volatility of reported pension costs. If necessary, the excess is amortized over the average remaining service period of active employees.

Due to the various regulatory treatments of the plans, our Consolidated Financial Statements reflect the effects of the different rate making principles followed by the jurisdictions regulating us. Pension costs in Montana and other postretirement benefit costs in South Dakota are included in rates on a pay as you go basis for regulatory purposes. Pension costs in South Dakota and other postretirement benefit costs in Montana are included in rates on an accrual basis for regulatory purposes. Regulatory assets have been recognized for the obligations that will be included in future cost of service.

Income Taxes

Judgment and the use of estimates are required in developing the provision for income taxes and reporting of tax-related assets and liabilities. Deferred income tax assets and liabilities represent the future effects on income taxes from temporary differences between the bases of assets and liabilities for financial reporting and tax purposes. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to reverse. The probability of realizing deferred tax assets is based on forecasts of future taxable income and the availability of tax planning strategies that can be implemented, if necessary, to realize deferred tax assets. We establish a valuation allowance when it is more likely than not that all, or a portion of, a deferred tax asset will not be realized. Exposures exist related to various tax filing positions, which may require an extended period of time to resolve and may result in income tax adjustments by taxing authorities. We have reduced deferred tax assets or established liabilities based on our best estimate of future probable adjustments related to these exposures. On a quarterly basis, we evaluate exposures in light of any additional information and make adjustments as necessary to reflect the best estimate of the future outcomes. We believe our deferred tax assets and established liabilities are appropriate for estimated exposures; however, actual results may differ significantly from these estimates.

The interpretation of tax laws involves uncertainty. Ultimate resolution of income tax matters may result in favorable or unfavorable impacts to net income and cash flows and adjustments to tax-related assets and liabilities could be material. The uncertainty and judgment involved in the determination and filing of income taxes is accounted for by prescribing a minimum recognition threshold that a tax position is required to meet before being recognized in the Consolidated Financial Statements. We recognize tax positions that meet the more-likely-than-not threshold as the largest amount of tax benefit that is greater than 50 percent likely of being realized upon ultimate settlement with a taxing authority that has full knowledge of all relevant information. We have unrecognized tax benefits of approximately $9.6 million as of December 31, 2024. The resolution of tax matters in a particular future period could have a material impact on our provision for income taxes, results of operations and our cash flows. See Note 12 - Income Taxes to the Consolidated Financial Statements for further discussion.

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NEW ACCOUNTING STANDARDS

See Note 2 - Significant Accounting Policies, to the Consolidated Financial Statements, included in Item 8 herein for a discussion of new accounting standards.

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FY 2023 10-K MD&A

SEC filing source: 0001993004-24-000006.

Extracted structurally from real Item 7 body heading to real Item 7A/8 boundary. Confidence: high. Filing date: 2024-02-15. Report date: 2023-12-31.

ITEM 7. MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

The following includes a discussion of our results of operations and cash flows for the year ended December 31, 2023 compared to the year ended December 31, 2022, on both a consolidated basis and on a segment basis. For a discussion of our financial results and cash flows for the year ended December 31, 2022 compared with the year ended December 31, 2021, see Management's Discussion and Analysis of Financial Condition and Results of Operations in our Annual Report on Form 10-K for the year ended December 31, 2022.

This discussion should be read in conjunction with our Consolidated Financial Statements and related notes contained elsewhere in this Annual Report on Form 10-K. For additional information related to our segments, see Note 20 - Segment and Related Information, to the Consolidated Financial Statements.

Non-GAAP Financial Measure

The following discussion includes financial information prepared in accordance with GAAP, as well as another financial measure, Utility Margin, that is considered a “non-GAAP financial measure.” Generally, a non-GAAP financial measure is a numerical measure of a company’s financial performance, financial position or cash flows that excludes (or includes) amounts that are included in (or excluded from) the most directly comparable measure calculated and presented in accordance with GAAP. We define Utility Margin as Operating Revenues less fuel, purchased supply and direct transmission expense (exclusive of depreciation and depletion) as presented in our Consolidated Statements of Income. This measure differs from the GAAP definition of Gross Margin due to the exclusion of Operating and maintenance, Property and other taxes, and Depreciation and depletion expenses, which are presented separately in our Consolidated Statements of Income. The following discussion includes a reconciliation of Utility Margin to Gross Margin, the most directly comparable GAAP measure.

We believe that Utility Margin provides a useful measure for investors and other financial statement users to analyze our financial performance in that it excludes the effect on total revenues caused by volatility in energy costs and associated regulatory mechanisms. This information is intended to enhance an investor's overall understanding of results. Under our various state regulatory mechanisms, as detailed below, our supply costs are generally collected from customers. In addition, Utility Margin is used by us to determine whether we are collecting the appropriate amount of energy costs from customers to allow for recovery of operating costs, as well as to analyze how changes in loads (due to weather, economic or other conditions), rates and other factors impact our results of operations. Our Utility Margin measure may not be comparable to that of other companies' presentations or more useful than the GAAP information provided elsewhere in this report.

OVERVIEW

NorthWestern Energy Group, doing business as NorthWestern Energy, provides electricity and/or natural gas to approximately 775,300 customers in Montana, South Dakota, Nebraska, and Yellowstone National Park. Our operations in Montana and Yellowstone National Park are conducted through our subsidiary, NW Corp, and our operations in South Dakota and Nebraska are conducted through our subsidiary, NWE Public Service. As you read this discussion and analysis, refer to our Consolidated Statements of Income, which present the results of our operations for 2023, 2022 and 2021. Following is a discussion of our strategy and significant trends.

We work to deliver safe, reliable and innovative energy solutions that create value for customers, communities, employees and investors. We do this by providing low-cost and reliable service performed by highly-adaptable and skilled employees. We are focused on delivering long-term shareholder value through:

•Infrastructure investment focused on a stronger and smarter grid to improve the customer experience, while enhancing grid reliability and safety. This includes automation in customer meters, distribution and substations that enables the use of proven new technologies.

•Investing in and integrating supply resources that balance reliability, cost, capacity, and sustainability considerations with more predictable long-term commodity prices.

•Continually improving our operating efficiency. Financial discipline is essential to earning our authorized return on invested capital and maintaining a strong balance sheet, stable cash flows, and quality credit ratings to continue to attract cost-effective capital for future investment.

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We expect to pursue these investment opportunities and manage our business in a manner that allows us to be flexible in adjusting to changing economic conditions by adjusting the timing and scale of the projects.

In 2023, approximately 55 percent of our retail needs from our owned and long-term contracted resources originated from carbon-free resources, compared to approximately 40 percent for the total U.S. electric power industry. We are committed to providing customers with reliable and affordable electric and natural gas services while also being good stewards of the environment. Towards this end, our efforts towards a carbon-free future are outlined through our goal to achieve net zero carbon emissions by 2050. Our vision for the future builds on the progress we have made, including our hydroelectric system in Montana, which is 100 percent carbon free and is readily available capacity. For us, wind generation is a close second and continues to grow. While utility-scale solar energy has not been a significant portion of our energy mix to date, we recently entered into power purchase agreements with two solar projects totaling 160-megawatts that began delivering energy to our Montana customers in 2023. We expect solar to further evolve along with advances in energy storage. We are committed to working with our customers and communities to help them achieve their sustainability goals and add new technology on our system.

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HOW WE PERFORMED IN 2023 COMPARED TO OUR 2022 RESULTS

Year Ended December 31, 2023 vs. 2022
Income Before Income TaxesIncome Tax Benefit (Expense)Net Income
(in millions)
Year ended December 31, 2022$182.4$0.6$183.0
Variance in revenue and fuel, purchased supply, and direct transmission expense(1) items impacting net income:
Montana rate review - new base rates32.6(8.3)24.3
Lower non-recoverable Montana electric supply costs14.2(3.6)10.6
Montana property tax tracker collections12.8(3.2)9.6
Higher Montana natural gas transportation2.2(0.6)1.6
Higher electric transmission revenue0.6(0.2)0.4
Lower natural gas retail volumes(7.0)1.8(5.2)
Lower electric retail volumes(1.8)0.5(1.3)
Higher revenue from lower production tax credits, offset within income tax benefit (expense)3.8(3.8)
Other(1.7)0.4(1.3)
Variance in expense items(2) impacting net income:
Higher depreciation expense(15.5)3.9(11.6)
Higher interest expense(14.5)3.7(10.8)
Higher operating, maintenance, and administrative expenses(14.4)3.6(10.8)
Lower property and other taxes not recoverable within trackers3.0(0.8)2.2
Other4.9(1.5)3.4
Year ended December 31, 2023$201.6$(7.5)$194.1
Change in Net Income$11.1

(1) Exclusive of depreciation and depletion shown separately below

(2) Excluding fuel, purchased supply, and direct transmission expense

Consolidated net income in 2023 was $194.1 million as compared with $183.0 million in 2022. This increase was primarily due to new base rates resulting from the Montana rate review, lower non-recoverable Montana electric supply costs, higher Montana property tax tracker collections, and lower property and other taxes not recoverable within trackers, partly offset by lower electric and natural gas retail volumes, higher depreciation and depletion expense, higher interest expense, higher operating, maintenance, and administrative expenses, and higher income tax expense.

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SIGNIFICANT TRENDS AND REGULATION

Regulatory Update

Rate reviews are necessary to recover the cost of providing safe, reliable service, while contributing to earnings growth and achieving our financial objectives. We regularly review the need for electric and natural gas rate relief in each state in which we provide service.

Montana Rate Review Filing – On October 27, 2023, the MPSC issued a final order approving the settlement agreement filed April 3, 2023. Final rates, adjusting from interim to settled rates, were effective November 1, 2023. For additional information related to our Montana Rate Review Filing, see Note 3 - Regulatory Matters to the Consolidated Financial Statements.

South Dakota Electric Rate Review Filing – In June 2023, we filed a South Dakota electric rate review filing (2022 test year) for an annual increase to electric rates totaling approximately $30.9 million. Our request was based on a rate of return of 7.54 percent, a capital structure including 50.5 percent equity, and rate base of $787.3 million. In January 2024, the SDPUC issued a final order approving the settlement agreement between NorthWestern and SDPUC Staff for an annual increase in base rates of approximately $21.5 million and an authorized rate of return of 6.81 percent. The approved settlement is based on a capital structure of 50.5 percent equity and a rate base of $791.8 million. Final rates were effective January 10, 2024. In addition, the SDPUC approved a phase in rate plan rider that allows for the recovery of capital investments not yet included in base rates.

Holding Company Reorganization – On October 2, 2023, NW Corp and NorthWestern Energy Group completed a merger transaction pursuant to which NorthWestern Energy Group became the holding company parent of NW Corp. In this reorganization, shareholders of NW Corp (the predecessor publicly held parent company) became shareholders of NorthWestern Energy Group, maintaining the same number of shares and ownership percentage as held in NW Corp immediately prior to the reorganization. NW Corp became a wholly-owned subsidiary of NorthWestern Energy Group. The transaction was effected pursuant to a merger pursuant to Section 251(g) of the General Corporation Law of the State of Delaware, which provides for the formation of a holding company without a vote of the shareholders of the constituent corporation. Immediately after consummation of the reorganization, NorthWestern Energy Group had, on a consolidated basis, the same assets, businesses and operations as NW Corp had immediately prior to the consummation of the reorganization. As a result of the reorganization, NorthWestern Energy Group became the successor issuer to NW Corp pursuant to Rule 12g-3(a) of the Securities Exchange Act of 1934, and as a result, NorthWestern Energy Group's common stock was deemed registered under Section 12(b) of the Securities Exchange Act of 1934. On January 1, 2024, we completed the second and final phase of the holding company reorganization. NW Corp contributed the assets and liabilities of its South Dakota and Nebraska regulated utilities to NWE Public Service, and then distributed its equity interest in NWE Public Service and certain other subsidiaries to NorthWestern Energy Group, resulting in NW Corp owning and operating the Montana regulated utility and NWE Public Service owning and operating the Nebraska and South Dakota utilities, each as a direct subsidiary of NorthWestern Energy Group.

Power Costs and Credits Adjustment Mechanism - The MPSC's September 2022 decision approving interim rates related to our Montana rate review included a $61.1 million increase to the PCCAM Base, from $138.7 million to $199.8 million, effective October 1, 2022. The MPSC's October 2023 decision approving the Montana rate review settlement agreement increased the PCCAM Base to $208.4 million, with retroactive application to July 1, 2022. We have under-collected our total Montana electric supply costs for the July 2022 through June 2023 PCCAM year by approximately $14.5 million, which includes a $2.9 million increase to our under-collection for this tracker period to reflect the retroactive application of the higher PCCAM Base rates effective July 1, 2022. As of December 31, 2023, we have over-collected our total Montana electric supply costs for the July 2023 through June 2024 PCCAM year by approximately $4.7 million.

Under the PCCAM, net costs higher or lower than the PCCAM Base (excluding QF costs) are allocated 90 percent to Montana customers and 10 percent to shareholders. For the twelve months ended December 31, 2023, we over collected supply costs of $32.9 million resulting in a reduction to our under collection of costs, and recorded an increase in pre-tax earnings of $7.0 million (10 percent of the PCCAM Base cost variance), which is inclusive of a $3.2 million increase in pre-tax earnings related to the retroactive application of higher PCCAM Base rates to July 1, 2022. For the twelve months ended December 31, 2022, we under collected costs of $64.8 million resulting in an increase to the under collection of costs, and recorded a reduction in pre-tax earnings of $7.2 million.

As discussed above, the approved Montana rate review settlement provides for an update to the PCCAM by adjusting the base costs from $138.7 million to $208.4 million and providing for more timely quarterly recovery of deferred balances instead of annual recovery. The updated $208.4 million PCCAM Base is retroactive to an effective date of July 1, 2022.

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Our electric supply from owned and long-term contracted resources is not adequate to meet our peak-demand needs. Because of this, the volatility of market prices for energy on peak-demand days, even if only for a few days in duration, exposes us to potentially significant market purchases that could negatively impact our results of operations and cash flows. See the Electric Resource Planning - Montana section below for how we are working to address this market exposure.

Electric Resource Planning - Montana

Yellowstone County 175 MW plant - Construction of the new generation facility continues to progress and we expect the plant to be operational no later than the end of the third quarter 2024. The lawsuit challenging the YCGS air quality permit, which required us to suspend construction activities for a period of time, as well as additional related legal and construction challenges, delayed the project timing and have increased costs. As of December 31, 2023, total costs of approximately $240.0 million have been incurred, with expected total costs of approximately $310.0 million to $320.0 million. See Note 18 - Commitments and Contingencies to the Consolidated Financial Statements included herein for additional information regarding legal challenges impacting YCGS.

Acquisition of Colstrip Interest - On January 16, 2023, we entered into a definitive agreement (the Avista Agreement) with Avista Corporation (Avista) to acquire Avista's 15 percent interest in each of Units 3 and 4 at the Colstrip Generating Station, a coal-fired, base-load electric generation facility located in Colstrip, Montana. The Avista Agreement provides that the purchase price will be $0 and that we will acquire Avista's interest effective December 31, 2025, subject to the satisfaction of the closing conditions contained within the Avista Agreement. Under the terms of this Avista Agreement, we will be responsible for operating costs starting on January 1, 2026; while Avista will retain responsibility for its pre-closing share of environmental and pension liabilities attributed to events or conditions existing prior to the closing of the transaction and for any future decommission and demolition costs associated with the existing facilities that comprise Avista's interest.

The Avista Agreement contains customary representations and warranties, covenants, and indemnification obligations, and the Avista Agreement is subject to customary conditions and approvals, including approval from the FERC. Closing also is conditioned on our ability to enter into a new coal supply agreement for Colstrip by December 31, 2024. Such coal supply agreement must provide a sufficient amount of coal to Colstrip to permit the generation of electric power by the maximum permitted capacity of the interest in Colstrip then held by us during the period from January 1, 2026 through, December 31, 2030.

Either party may terminate the Avista Agreement if any requested regulatory approval is denied or if the closing has not occurred by December 31, 2025 or if any law or order would delay or impair closing.

The acquisition of an additional interest under this Avista Agreement in 2026 will provide capacity to help us meet our obligation to provide reliable and cost effective power to our customers in Montana, while allowing opportunity for us to identify and plan for newer technologies to provide reliable, affordable and carbon free power through our IRP process.

Future Integrated Resource Planning - Resource adequacy in the Western third of the U.S. has been declining with the retirement of thermal power plants. Our owned and long-term contracted resources are inadequate to supply the necessary capacity we require to meet our peak-demand loads, which exposes us to large quantities of market purchases at typically high and volatile energy prices. To comply with regulatory resource planning requirements, we submitted an IRP to the MPSC on April 28, 2023.

We remain concerned regarding an overall lack of capacity in the West and our owned and long-term contracted capacity deficit to meet peak-demand loads. The construction of the Yellowstone County Generating Station and acquisition of Avista's Colstrip Units 3 and 4 interests are expected to reduce our exposure to market purchases.

Proposed EPA Rules

In May 2023, the EPA proposed new GHG emissions standards for coal and natural gas-fired plants. In particular, the proposed rules would (i) strengthen the current New Source Performance Standards for newly built fossil fuel-fired stationary combustion turbines (generally natural gas-fired); (ii) establish emission guidelines for states to follow in limiting carbon pollution from existing fossil fuel-fired steam generating electric generating units (including coal, oil and natural gas-fired units); and (iii) establish emission guidelines for large, frequently used existing fossil fuel-fired stationary combustion turbines (generally natural gas-fired). In addition, in April 2023, EPA proposed to amend the MATS. Among other things, MATS currently sets stringent emission limits for acid gases, mercury, and other hazardous air pollutants from new and existing electric generating units. We are in compliance with existing MATS requirements. The proposed amendment of the MATS would strengthen the MATS requirements, and if adopted as written, both the GHG and MATS proposed rules could have a material negative impact on our coal-fired plants, including requiring potentially expensive upgrades or the early retirement of Colstrip Unit's 3 and 4 due to the rules making the facility uneconomic.

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Previous efforts by the EPA were met with extensive litigation and we anticipate a similar response if the proposed rules are adopted. As MATS and GHG regulations are implemented, it could result in additional material compliance costs. We will continue working with federal and state regulatory authorities, other utilities, and stakeholders to seek relief from any MATS or GHG regulations that, in our view, disproportionately impact customers in our region.

Electric Resource Supply - South Dakota

Our electric supply resource plans for South Dakota continue to identify portfolio requirements including potential investments resulting from a completed competitive solicitation process. We anticipate filing the next resource plan in the summer of 2024.

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SIGNIFICANT INFRASTRUCTURE INVESTMENTS AND INITIATIVES

Our estimated capital expenditures for the next five years, including our electric and natural gas transmission and distribution and electric generation infrastructure investment plan, are as follows (in millions):

Electric Supply Resource Plans - Our energy resource plans identify portfolio resource requirements including potential investments. For additional information related to our electric supply resource plans, see Item 1. Business, where we discuss electric resource planning for our Montana and South Dakota jurisdictions.

Distribution and Transmission Modernization and Maintenance - The primary goals of our infrastructure investments are to reverse the trend in aging infrastructure, maintain reliability, proactively manage safety, build capacity into the system, and prepare our network for the adoption of new technologies. We are taking a proactive and pragmatic approach to replacing these assets while also evaluating the implementation of additional technologies to prepare the overall system for smart grid applications. Over $1.8 billion or 75 percent of our capital forecast above is projected to be spent on our distribution and transmission system. Beginning in 2021, and continuing through 2025, we expect to install automated metering infrastructure in Montana at a total cost of approximately $134.0 million, of which $41.7 million remains and is reflected in the five year capital forecast above.

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RESULTS OF OPERATIONS

Our consolidated results include the results of our divisions and subsidiaries constituting each of our business segments. The overall consolidated discussion is followed by a detailed discussion of utility margin by segment.

Factors Affecting Results of Operations

Our revenues may fluctuate substantially with changes in supply costs, which are generally collected in rates from customers. In addition, various regulatory agencies approve the prices for electric and natural gas utility service within their respective jurisdictions and regulate our ability to recover costs from customers.

Revenues are also impacted by customer growth and usage, the latter of which is primarily affected by weather and the impact of energy efficiency initiatives and investment. Very cold winters increase demand for natural gas and to a lesser extent, electricity, while warmer than normal summers increase demand for electricity, especially among our residential and commercial customers. We measure this effect using degree-days, which is the difference between the average daily actual temperature and a baseline temperature of 65 degrees. Heating degree-days result when the average daily temperature is less than the baseline. Cooling degree-days result when the average daily temperature is greater than the baseline. The statistical weather information in our regulated segments represents a comparison of this data.

Fuel, purchased supply and direct transmission expenses are costs directly associated with the generation and procurement of electricity and natural gas. These costs are generally collected in rates from customers and may fluctuate substantially with market prices and customer usage.

Operating and maintenance expenses are costs associated with the ongoing operation of our vertically-integrated utility facilities which provide electric and natural gas utility products and services to our customers. Among the most significant of these costs are those associated with direct labor and supervision, repair and maintenance expenses, and contract services. These costs are normally fairly stable across broad volume ranges and therefore do not normally increase or decrease significantly in the short term with increases or decreases in volumes.

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OVERALL CONSOLIDATED RESULTS

Year Ended December 31, 2023 Compared with Year Ended December 31, 2022

Consolidated net income in 2023 was $194.1 million as compared with $183.0 million in 2022, an increase of $11.1 million. As described in more detail below, this increase was primarily due to new base rates resulting from the Montana rate review, lower non-recoverable Montana electric supply costs, higher Montana property tax tracker collections, and lower property and other taxes not recoverable within trackers, partly offset by lower electric and natural gas retail volumes, higher depreciation and depletion expense, higher interest expense, higher operating, maintenance, and administrative expenses, and higher income tax expense.

Consolidated gross margin in 2023 was $416.3 million as compared with $376.9 million in 2022, an increase of $39.4 million or 10.5 percent. This increase was primarily due to new base rates resulting from the Montana rate review, lower non-recoverable Montana electric supply costs, higher Montana property tax tracker collections, and lower property and other taxes not recoverable within trackers, partly offset by lower electric and natural gas retail volumes, higher depreciation and depletion expense, and higher operating and maintenance expense.

ElectricNatural GasTotal
202320222023202220232022
(in millions)
Reconciliation of gross margin to utility margin:
Operating Revenues$1,068.8$1,106.5$353.3$371.3$1,422.1$1,477.8
Less: Fuel, purchased supply and direct transmission expense (exclusive of depreciation and depletion shown separately below)262.7324.4157.5167.6420.2492.0
Less: Operating and maintenance166.0167.854.553.6220.5221.4
Less: Property and other taxes120.3149.834.342.7154.6192.5
Less: Depreciation and depletion174.1162.436.432.6210.5195.0
Gross Margin345.7302.170.674.8416.3376.9
Operating and maintenance166.0167.854.553.6220.5221.4
Property and other taxes120.3149.834.342.7154.6192.5
Depreciation and depletion174.1162.436.432.6210.5195.0
Utility Margin(1)$806.1$782.1$195.8$203.7$1,001.9$985.8

(1) Non-GAAP financial measure. See "Non-GAAP Financial Measure" above.

Year Ended December 31,
20232022Change% Change
(in millions)
Utility Margin
Electric$806.1$782.1$24.03.1%
Natural Gas195.8203.7(7.9)(3.9)
Total Utility Margin(1)$1,001.9$985.8$16.11.6%

(1) Non-GAAP financial measure. See "Non-GAAP Financial Measure" above.

Consolidated utility margin in 2023 was $1,001.9 million as compared with $985.8 million in 2022, an increase of $16.1 million, or 1.6 percent.

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Primary components of the change in utility margin include the following (in millions):

Utility Margin2023 vs. 2022
Utility Margin Items Impacting Net Income
Montana rate review - new base rates$32.6
Lower non-recoverable Montana electric supply costs14.2
Montana property tax tracker collections12.8
Higher Montana natural gas transportation2.2
Higher electric transmission revenue due to market conditions0.6
Lower natural gas retail volumes(7.0)
Lower electric retail volumes(1.8)
Other(1.7)
Change in Utility Margin Impacting Net Income51.9
Utility Margin Items Offset Within Net Income
Lower property taxes recovered in revenue, offset in property tax expense(35.8)
Lower operating expenses recovered in revenue, offset in operating and maintenance expense(3.1)
Lower gas production taxes recovered in revenue, offset in property and other taxes(0.7)
Higher revenue from lower production tax credits, offset in income tax expense3.8
Change in Items Offset Within Net Income(35.8)
Increase in Consolidated Utility Margin(1)$16.1

(1) Non-GAAP financial measure. See "Non-GAAP Financial Measure" above.

Lower non-recoverable Montana electric supply costs were driven by higher electric supply revenues, lower electric supply costs, and $3.2 million for the retroactive application of higher PCCAM base rates approved in the Montana rate review.

Lower electric retail volumes were driven by unfavorable weather in Montana impacting residential demand and lower commercial demand as compared to the prior year, partly offset by customer growth. Lower natural gas retail volumes were driven by unfavorable weather in Montana, partly offset by favorable weather in Nebraska and customer growth.

Year Ended December 31,
20232022Change% Change
(in millions)
Operating Expenses (excluding fuel, purchased supply and direct transmission expense)
Operating and maintenance$220.5$221.4$(0.9)(0.4)%
Administrative and general117.3113.83.53.1
Property and other taxes153.1192.5(39.4)(20.5)
Depreciation and depletion210.5195.015.57.9
Total Operating Expenses (excluding fuel, purchased supply and direct transmission expense)$701.4$722.7$(21.3)(2.9)%

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Consolidated operating expenses, excluding fuel, purchased supply and direct transmission expense, were $701.4 million in 2023, as compared with $722.7 million in 2022. Primary components of the change include the following (in millions):

Operating Expenses
2023 vs. 2022
Operating Expenses (excluding fuel, purchased supply and direct transmission expense) Impacting Net Income
Higher depreciation expense due to plant additions$15.5
Higher labor and benefits expense, partly offset by higher capitalization of labor and benefits costs(1)6.1
Higher insurance expense2.1
Increase in uncollectible accounts1.1
Higher expenses at our electric generation facilities1.0
Higher cost of materials0.8
Lower property and other taxes not recoverable within trackers(3.0)
Other3.3
Change in Items Impacting Net Income26.9
Operating Expenses Offset Within Net Income
Lower property and other taxes recovered in trackers, offset in revenue(35.8)
Lower pension and other postretirement benefits, offset in other income(1)(8.7)
Lower operating expenses recovered in trackers, offset in revenue(3.1)
Lower natural gas production taxes recovered in trackers, offset in revenue(0.7)
Higher deferred compensation, offset in other income0.1
Change in Items Offset Within Net Income(48.2)
Decrease in Operating Expenses (excluding fuel, purchased supply and direct transmission expense)$(21.3)

(1) In order to present the total change in labor and benefits, we have included the change in the non-service cost component of our pension and other postretirement benefits, which is recorded within other income on our Condensed Consolidated Statements of Income. This change is offset within this table as it does not affect our operating expenses.

Consolidated operating income in 2023 was $300.5 million as compared with $263.1 million in 2022. This increase was primarily due to new base rates resulting from the Montana rate review, lower non-recoverable Montana electric supply costs, higher Montana property tax tracker collections, and lower property and other taxes not recoverable within trackers, partly offset by lower electric and natural gas retail volumes, higher depreciation and depletion expense, and higher operating, maintenance, and administrative expense.

Consolidated interest expense in 2023 was $114.6 million, as compared with $100.1 million in 2022. This increase was due to higher borrowings and interest rates, partly offset by higher capitalization of AFUDC.

Consolidated other income in 2023 was $15.8 million, as compared with $19.4 million in 2022. This decrease was primarily due to an increase in the non-service cost component of pension expense, partly offset by the prior year CREP penalty and higher capitalization of AFUDC.

Consolidated income tax expense in 2023 was $7.5 million, as compared to an income tax benefit of $0.6 million in 2022. Our effective tax rate for the twelve months ended December 31, 2023 was 3.7 percent as compared with (0.3) percent for the same period of 2022. Income tax expense for the twelve months ended December 31, 2023, includes a one-time $3.2 million expense for the reduction of previously claimed alternative minimum tax credits as well as a $3.2 million benefit related to a reduction in our unrecognized tax benefits. We currently estimate our effective tax rate will range between 12.0 percent to 14.0 percent in 2024. Based on the significant NOL we generated during the year ended December 31, 2023, we anticipate paying minimal cash for income taxes into 2028.

The following table summarizes the differences between our effective tax rate and the federal statutory rate (in millions):

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Year Ended December 31,
20232022
Income Before Income Taxes$201.6$182.4
Income tax calculated at federal statutory rate42.421.0%38.321.0%
Permanent or flow through adjustments:
State income taxes, net of federal provisions0.60.30.60.3
Flow-through repairs deductions(25.9)(12.9)(22.7)(12.4)
Production tax credits(10.3)(5.1)(13.2)(7.2)
Unregulated Tax Cuts and Jobs Act excess deferred income taxes(3.4)(1.7)
Release of unrecognized tax benefits(3.2)(1.6)
Amortization of excess deferred income taxes(2.2)(1.1)(1.7)(0.9)
Plant and depreciation of flow through items6.63.3(0.2)(0.1)
Reduction to previously claimed alternative minimum tax credit3.21.6
Prior year permanent return to accrual adjustments0.00.0(1.4)(0.8)
Other, net(0.3)(0.1)(0.3)(0.2)
(34.9)(17.3)(38.9)(21.3)
Income Tax Expense (Benefit)$7.53.7%$(0.6)(0.3)%

Our effective tax rate typically differs from the federal statutory tax rate primarily due to the regulatory impact of flowing through federal and state tax benefits of repairs deductions, state tax benefit of accelerated tax depreciation deductions (including bonus depreciation when applicable) and production tax credits.

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ELECTRIC OPERATIONS

We have various classifications of electric revenues, defined as follows:

•Retail: Sales of electricity to residential, commercial and industrial customers, and the impact of regulatory mechanisms.

•Regulatory amortization: Primarily represents timing differences for electric supply costs and property taxes between when we incur these costs and when we recover these costs in rates from our customers, which is also reflected in fuel, purchased supply and direct transmission expense and therefore has minimal impact on utility margin. The amortization of these amounts are offset in retail revenue.

•Transmission: Reflects transmission revenues regulated by the FERC.

•Wholesale and other are largely utility margin neutral as they are offset by changes in fuel, purchased supply and direct transmission expense.

Year Ended December 31, 2023 Compared with Year Ended December 31, 2022

RevenuesChangeMWHsAvg. Customer Counts
20232022$%2023202220232022
(in thousands)
Montana$408,341$357,384$50,95714.3%2,7952,868322,489316,968
South Dakota67,88869,809(1,921)(2.8)60359651,26151,069
Residential476,229427,19349,03611.53,3983,464373,750368,037
Montana431,357368,63462,72317.03,2383,23774,43873,093
South Dakota103,194108,202(5,008)(4.6)1,1011,11412,97312,897
Commercial534,551476,83657,71512.14,3394,35187,41185,990
Industrial45,95839,7736,18515.62,6602,5907976
Other32,75631,0071,7495.61341616,4436,406
Total Retail Electric$1,089,494$974,809$114,68511.8%10,53110,566467,683460,509
Regulatory amortization(105,608)46,382(151,990)(327.7)
Transmission78,43677,7916450.8
Wholesale and Other6,5117,583(1,072)(14.1)
Total Revenues$1,068,833$1,106,565$(37,732)(3.4)%
Fuel, purchased supply and direct transmission expense(1)262,755324,434(61,679)(19.0)
Utility Margin(2)$806,078$782,131$23,9473.1%

(1) Exclusive of depreciation and depletion.

(2) Non-GAAP financial measure. See “Non-GAAP Financial Measure” above. Also see "Overall Consolidated Results" above for reconciliation of gross margin to utility margin.

Cooling Degree Days2023 as compared with:
20232022Historic Average2022Historic Average
Montana44160245527% cooler3% cooler
South Dakota1,0359537529% warmer38% warmer
Heating Degree Days2023 as compared with:
20232022Historic Average2022Historic Average
Montana(1)7,2378,0047,59210% warmer5% warmer
South Dakota7,6657,6877,675remained flatremained flat

(1) Montana electric and natural gas heating degree days may differ due to differences in service territory.

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The following summarizes the components of the changes in electric utility margin for the years ended December 31, 2023 and 2022 (in millions):

Utility Margin2023 vs. 2022
Utility Margin Items Impacting Net Income
Montana rate review - new electric base rates$29.5
Lower non-recoverable Montana electric supply costs14.2
Montana property tax tracker collections9.5
Higher electric transmission revenue due to market conditions0.6
QF liability adjustment(0.1)
Lower retail volumes(1.8)
Other(0.3)
Change in Utility Margin Items Impacting Net Income51.6
Utility Margin Items Offset Within Net Income
Lower property taxes recovered in revenue, offset in property tax expense(28.1)
Lower operating expenses recovered in revenue, offset in operating and maintenance expense(3.3)
Higher revenue from lower production tax credits, offset in income tax expense3.8
Change in Items Offset Within Net Income(27.6)
Increase in Utility Margin(1)$24.0

(1) Non-GAAP financial measure. See "Non-GAAP Financial Measure" above. Also see "Overall Consolidated Results" above for reconciliation of gross margin to utility margin.

Lower non-recoverable Montana electric supply costs were driven by higher electric supply revenues, lower electric supply costs, and $3.2 million for the retroactive application of higher PCCAM base rates approved in the Montana rate review.

Lower retail volumes were driven by unfavorable weather in Montana impacting residential demand and lower commercial demand as compared to the prior year, partly offset by customer growth.

The adjustment to our electric QF liability (unrecoverable costs associated with contracts covered by the Public Utility Regulatory Policies Act of 1978 (PURPA) as part of a 2002 stipulation with the MPSC and other parties) reflects a $5.0 million gain in 2023, as compared with a $5.1 million gain for the same period in 2022, due to the combination of:

•A $0.8 million favorable reduction in costs for the current contract year to record the annual adjustment for actual output and pricing as compared with a $1.8 million favorable reduction in costs in the prior period; and

•A favorable adjustment, decreasing the QF liability by $4.2 million, reflecting annual actual contract price escalation for the 2023-2024 contract year, which was less than previously estimated. The 2023-2024 contract year is the last year of the contract that contains variable pricing terms. This is compared to a favorable adjustment of $3.3 million in the prior year due to less than previously estimated actual price escalation.

The change in regulatory amortization revenue is due to timing differences between when we incur electric supply costs and when we recover these costs in rates from our customers, which has a minimal impact on utility margin. Our wholesale and other revenues are largely utility margin neutral as they are offset by changes in fuel, purchased supply and direct transmission expenses.

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NATURAL GAS OPERATIONS

We have various classifications of natural gas revenues, defined as follows:

•Retail: Sales of natural gas to residential, commercial and industrial customers, and the impact of regulatory mechanisms.

•Regulatory amortization: Primarily represents timing differences for natural gas supply costs and property taxes between when we incur these costs and when we recover these costs in rates from our customers, which is also reflected in fuel, purchased supply and direct transmission expenses and therefore has minimal impact on utility margin. The amortization of these amounts are offset in retail revenue.

•Wholesale: Primarily represents transportation and storage for others.

Year Ended December 31, 2023 Compared with Year Ended December 31, 2022

RevenuesChangeDekathermsAvg. Customer Counts
20232022$%2023202220232022
(in thousands)
Montana$136,097$152,343(16,246)(10.7)%14,00815,319183,810181,879
South Dakota36,63839,178(2,540)(6.5)3,1793,28042,05341,524
Nebraska35,53935,756(217)(0.6)2,5812,55837,79337,693
Residential208,274227,277(19,003)(8.4)19,76821,157263,656261,096
Montana73,72179,274(5,553)(7.0)8,0368,32925,72525,319
South Dakota25,86928,487(2,618)(9.2)3,1692,9817,2327,058
Nebraska22,11422,071430.21,9161,8465,0235,003
Commercial121,704129,832(8,128)(6.3)13,12113,15637,98037,380
Industrial1,3921,520(128)(8.4)157163232232
Other1,6811,932(251)(13.0)209232190178
Total Retail Gas$333,051$360,561$(27,510)(7.6)%33,25534,708302,058298,886
Regulatory amortization(25,012)(27,964)2,952(10.6)
Wholesale and other45,27138,6756,59617.1
Total Revenues$353,310$371,272$(17,962)(4.8)%
Fuel, purchased supply and direct transmission expense(1)157,507167,577(10,070)(6.0)
Utility Margin(2)$195,803$203,695$(7,892)(3.9)%

(1) Exclusive of depreciation and depletion.

(2) Non-GAAP financial measure. See “Non-GAAP Financial Measure” above. Also see "Overall Consolidated Results" above for reconciliation of gross margin to utility margin.

Heating Degree Days2023 as compared with:
20232022Historic Average2022Historic Average
Montana(1)7,4788,1947,7919% warmer4% warmer
South Dakota7,6657,6877,675remained flatremained flat
Nebraska5,8935,7676,0442% colder2% warmer

(1) Montana electric and natural gas heating degree days may differ due to differences in service territory.

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The following summarizes the components of the changes in natural gas utility margin for the years ended December 31, 2023 and 2022 (in millions):

Utility Margin2023 vs. 2022
Utility Margin Items Impacting Net Income
Montana property tax tracker collections$3.3
Montana rate review - new natural gas base rates3.1
Higher Montana natural gas transportation2.2
Lower retail volumes(7.0)
Other(1.3)
Change in Utility Margin Impacting Net Income0.3
Utility Margin Items Offset Within Net Income
Lower property taxes recovered in revenue, offset in property tax expense(7.7)
Lower gas production taxes recovered in revenue, offset in property and other taxes(0.7)
Higher operating expenses recovered in revenue, offset in operating and maintenance expense0.2
Change in Items Offset Within Net Income(8.2)
Decrease in Utility Margin(1)$(7.9)

(1) Non-GAAP financial measure. See "Non-GAAP Financial Measure" above. Also see "Overall Consolidated Results" above for reconciliation of gross margin to utility margin.

Lower retail volumes were driven by unfavorable weather in Montana, partly offset by favorable weather in Nebraska and customer growth.

Our wholesale and other revenues are largely utility margin neutral as they are offset by changes in fuel, purchased supply and direct transmission expenses.

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LIQUIDITY AND CAPITAL RESOURCES

Liquidity

We require liquidity to support and grow our business, and use our liquidity for working capital needs, capital expenditures, investments in or acquisitions of assets, and to repay debt. For NorthWestern Energy Group, liquidity is primarily provided through its revolving credit facility and dividends from its utility operating subsidiaries, NW Corp and NWE Public Service. These subsidiaries are subject to certain restrictions that may limit the amount of their dividend distributions. See Note 16 - Common Stock to the Consolidated Financial Statements for more information regarding these dividend restrictions.

We believe our cash flows from operations, existing borrowing capacity, debt and equity issuances and future utility rate increases should be sufficient to fund our operations, service existing debt, pay dividends, and fund capital expenditures. We plan to maintain a 50 - 55 percent debt to total capital ratio excluding finance leases, and expect to continue targeting a long-term dividend payout ratio of 60 - 70 percent of earnings per share; however, there can be no assurance that we will be able to meet these targets.

As of December 31, 2023, our total consolidated net liquidity was approximately $241.2 million, including $9.2 million of cash and $232.0 million of revolving credit facility availability with no letters of credit outstanding.

Cash Flows

The following table summarizes our consolidated cash flows (in millions):

Year Ended December 31,
20232022
Operating Activities
Net income$194.1$183.0
Non-cash adjustments to net income210.1183.1
Changes in working capital115.6(37.0)
Other noncurrent assets and liabilities(30.6)(21.9)
Cash Provided by Operating Activities489.2307.2
Investing Activities
Property, plant and equipment additions(566.9)(515.1)
Investment in equity securities(3.9)(1.7)
Cash Used in Investing Activities(570.8)(516.8)
Financing Activities
Proceeds from issuance of common stock, net73.6277.0
Issuance of long-term debt300.0
Dividends on common stock(154.1)(140.1)
Line of credit (repayments) borrowings, net(132.0)77.0
Financing costs(4.3)(1.2)
Other1.10.6
Cash Provided by Financing Activities84.3213.3
Net Increase in Cash, Cash Equivalents, and Restricted Cash$2.7$3.7
Cash, Cash Equivalents, and Restricted Cash, beginning of period$22.5$18.8
Cash, Cash Equivalents, and Restricted Cash, end of period$25.2$22.5

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Operating Activities

As of December 31, 2023, cash, cash equivalents, and restricted cash were $25.2 million as compared with $22.5 million as of December 31, 2022. Cash provided by operating activities totaled $489.2 million for the year ended December 31, 2023 as compared with $307.2 million for the year ended December 31, 2022. As shown in the table below, this increase in operating cash flows is primarily due to a $123.9 million improvement in net cash inflows for previously uncollected energy supply costs and interim and final rates from our Montana rate review.

Net under-collected supply costs (in millions)
Beginning of yearEnd of yearNet cash inflows
2022$99.1$115.4$(16.3)
2023$115.4$7.8$107.6
Improvement in annual net cash inflows$123.9

As discussed above, on October 27, 2023 the MPSC issued their final order approving our Montana rate review settlement which included an update to the PCCAM by adjusting the base costs from $138.7 million to $208.4 million and providing for more timely quarterly recovery of deferred balances instead of annual recovery. The updated $208.4 million PCCAM Base is retroactive to an effective date of July 1, 2022. As of December 31, 2023, we have under-collected our total Montana electric supply costs for the July 2022 through June 2023 PCCAM year by approximately $14.5 million that we began collecting in October 2023. As of December 31, 2023, we have over-collected our total Montana electric supply costs for the July 2023 through June 2024 PCCAM year by approximately $4.7 million.

With the adjusted PCCAM Base, we anticipate continued improvements in our cash flows from operations. However, continued higher overall market prices, which could be further exacerbated by extreme weather events, could create additional costs with deferred recovery that would offset these anticipated cash flow improvements.

Investing Activities

Cash used in investing activities totaled $570.8 million during the year ended December 31, 2023, as compared with $516.8 million during 2022. Plant additions during 2023 include capital maintenance additions of approximately $321.9 million and capacity related capital expenditures of approximately $245.0 million. Plant additions during 2022 included capital maintenance additions of approximately $295.4 million and capacity related capital expenditures of approximately $219.7 million. As discussed above in the “Significant Infrastructure Investments and Initiatives” section, our capital expenditures are forecasted to be $500 million in 2024.

Financing Activities

Cash provided by financing activities totaled $84.3 million during the year ended December 31, 2023 as compared with $213.3 million during the year ended December 31, 2022. During the year ended December 31, 2023, cash provided by financing activities reflects net proceeds from the issuance of debt of $300.0 million and proceeds received from the issuance of common stock of $73.6 million, partly offset by payment of dividends of $154.1 million and net repayments under our revolving lines of credit of $132.0 million. During the year ended December 31, 2022, cash provided by financing activities reflects proceeds received from the issuance of common stock of $277.0 million and net issuances under our revolving lines of credit of $77.0 million, partly offset by payment of dividends of $140.1 million.

Cash Requirements and Capital Resources

We believe our cash flows from operations, existing borrowing capacity, debt and equity issuances and future rate increases should be sufficient to satisfy our material cash requirements over the short-term and the long-term. As a rate-regulated utility our customer rates are generally structured to recover expected operating costs, with an opportunity to earn a return on our invested capital. This structure supports recovery for many of our operating expenses, although there are situations where the timing of our cash outlays results in increased working capital requirements. Due to the seasonality of our utility business, our short-term working capital requirements typically peak during the coldest winter months and warmest summer months when we cover the lag between when purchasing energy supplies and when customers pay for these costs. Our credit facilities may also be utilized for funding cash requirements during seasonally active construction periods, with peak activity during warmer months. Our cash requirements also include a variety of contractual obligations as outlined below in the “Contractual Obligations and Other Commitments” section.

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Our material cash requirements are also related to investment in our business through our capital expenditure program, which is discussed above in the “Significant Infrastructure Investments and Initiatives” section. Our capital expenditures are forecasted to be $500 million in 2024, $506 million in 2025, and $463 million in 2026. We anticipate funding capital expenditures through cash flows from operations, available credit sources, debt issuances and future rate increases. The actual amount of capital expenditures is subject to certain factors including the impact that a material change in operations, available financing, supply chain issues, or inflation could impact our current liquidity and ability to fund capital resource requirements. Events such as these could cause us to defer a portion of our planned capital expenditures, as necessary. To fund our strategic growth opportunities, we evaluate the additional capital need in balance with debt capacity and equity issuances that would be intended to allow us to maintain investment grade ratings.

Credit Facilities

Liquidity is generally provided by internal operating cash flows and the use of our unsecured revolving credit facilities. We utilize availability under our revolving credit facilities to manage our cash flows due to the seasonality of our business and to fund capital investment. Cash on hand in excess of current operating requirements is generally used to invest in our business and reduce borrowings.

For further information on our credit facilities, see Note 10 - Unsecured Credit Facilities to the Consolidated Financial Statements included herein.

The following table presents additional information about borrowings under our revolving credit facilities during the year ended December 31, 2023 (in millions):

Amount outstanding at year end$318.0
Daily average amount outstanding$228.4
Maximum amount outstanding$490.0
Minimum amount outstanding$54.0

As discussed further within Note 10 - Unsecured Credit Facilities, our credit facility availability as of December 31, 2023 was $232.0 million. With the completion of the holding company reorganization and associated restructuring of our credit facilities on January 1, 2024, our total credit facility availability increased by $50.0 million to $282.0 million.

As of February 9, 2024, availability under our revolving credit facilities was approximately $325.0 million, and there were no letters of credit outstanding.

Long-term Debt and Equity

We generally issue long-term debt to refinance other long-term debt maturities and borrowings under our revolving credit facilities, as well as to fund long-term capital investments and strategic opportunities. We have $100 million of debt maturing in 2024, which we intend to refinance.

For further information on our long-term debt, see Note 11 - Long-Term Debt and Finance Leases to the Consolidated Financial Statements included herein.

We generally issue equity securities to fund long-term investment in our business. We evaluate our equity issuance needs to support our plan to maintain a 50 - 55 percent debt to total capital ratio excluding finance leases.

For further information regarding equity, see Note 16 - Common Stock to the Consolidated Financial Statements included herein.

Credit Ratings

In general, less favorable credit ratings make debt financing more costly and more difficult to obtain on terms that are favorable to us and our customers, may impact our trade credit availability, and could result in the need to issue additional equity securities. Fitch Ratings (Fitch), Moody's Investors Service (Moody's), and S&P Global Ratings (S&P) are independent credit-rating agencies that rate our debt securities. These ratings indicate the agencies’ assessment of our ability to pay interest and principal when due on our debt. As of February 9, 2024, our current ratings with these agencies are as follows:

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Issuer RatingSenior Secured RatingSenior Unsecured RatingOutlook
NorthWestern Energy Group
Fitch(1)(2)BBB-BBBStable
Moody’s----
S&P(2)BBB--Stable
NW Corp
Fitch(1)(2)BBBA-BBB+Stable
Moody’s(2)Baa2A3Baa2Stable
S&P(2)BBBA--Stable
NWE Public Service
Fitch(1)(2)BBBA-BBB+Stable
Moody’s(2)Baa2A3-Stable
S&P(2)BBBA--Stable

(1) This Fitch Issuer Rating represents the Issuer Default Rating.

(2) As part of completing the holding company reorganization, NorthWestern Energy Group and NWE Public Service received their credit ratings from these agencies in December 2023. These agencies also affirmed their ratings for NW Corp.

A security rating is not a recommendation to buy, sell or hold securities. Such rating may be subject to revision or withdrawal at any time by the credit rating agency and each rating should be evaluated independently of any other rating.

Contractual Obligations and Other Commitments

We have a variety of contractual obligations and other commitments that require payment of cash at certain specified periods. With the exception of maturities of long-term debt, we anticipate funding these obligations through cash flows from operations. The following table summarizes our contractual cash obligations and commitments as of December 31, 2023. See additional discussion in Note 18 - Commitments and Contingencies to the Consolidated Financial Statements.

Total20242025202620272028Thereafter
(in thousands)
Long-term debt(1)$2,797,660$100,000$300,000$105,000$$497,660$1,795,000
Finance leases8,7993,3383,5961,865
Estimated pension and other postretirement obligations(2)57,40212,55411,43711,13711,13711,137N/A
QF liability(3)303,06274,11060,36055,39356,66542,40014,134
Supply and capacity contracts(4)2,828,615321,853244,091263,407243,576225,9161,529,772
Contractual interest payments on debt(5)1,592,745123,354114,385108,295106,636101,9681,038,107
Commitments for significant capital projects(6)45,94545,945$
Total Commitments(7)$7,634,228$681,154$733,869$545,097$418,014$879,081$4,377,013

(1) Represents cash payments for long-term debt and excludes $13.1 million of debt discounts and debt issuance costs, net.

(2) We have estimated cash obligations related to our pension and other postretirement benefit programs for five years, as it is not practicable to estimate thereafter. The pension and other postretirement benefit estimates reflect our expected cash contributions, which may be in excess of minimum funding requirements.

(3) Certain QFs require us to purchase minimum amounts of energy at prices ranging from $67 to $136 per MWH through 2029. Our estimated gross contractual obligation related to these QFs is approximately $303.1 million. A portion of the costs incurred to purchase this energy is recoverable through rates authorized by the MPSC, totaling approximately $266.5 million.

(4) We have entered into various purchase commitments, largely purchased power, electric transmission, coal and natural gas supply and natural gas transportation contracts (exclusive of the qualifying facilities liability discussed above). These commitments range from one to 24 years.

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The energy supply costs incurred under these contracts are generally recoverable through rate mechanisms approved by the MPSC, as further described in Note 3 - Regulatory Matters.

(5) Contractual interest payments include our revolving credit facilities, which have a variable interest rate. We have assumed an average interest rate of 6.71 percent on the outstanding balance through maturity of the credit facilities.

(6) Represents significant firm purchase commitments for construction of planned capital projects.

(7) The table above excludes potential tax payments related to uncertain tax positions as they are not practicable to estimate. Additionally, the table above excludes reserves for environmental remediation (See Note 18 - Commitments and Contingencies) and AROs (see Note 6 - Asset Retirement Obligations) as the amount and timing of cash payments may be uncertain.

Other Obligations - As a co-owner of Colstrip, we provided surety bonds of approximately $15.7 million and $17.3 million as of December 31, 2023 and 2022, respectively, to ensure the operation and maintenance of remedial and closure actions are carried out related to the Administrative Order on Consent Regarding Impacts Related to Wastewater Facilities Comprising the Closed-Loop System at Colstrip Steam Electric Stations, Colstrip Montana (the AOC) as required by the MDEQ. As costs are incurred under the AOC, the surety bonds will be reduced.

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CRITICAL ACCOUNTING ESTIMATES

Management's discussion and analysis of financial condition and results of operations is based on our Consolidated Financial Statements, which have been prepared in accordance with GAAP. The preparation of these Consolidated Financial Statements requires us to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses, and related disclosure of contingent assets and liabilities. We base our estimates on historical experience and other assumptions that are believed to be proper and reasonable under the circumstances. We continually evaluate the appropriateness of our estimates and assumptions. Actual results could differ from those estimates.

We have identified the policies and related procedures below that contain accounting estimates that involve a significant level of estimation uncertainty and have had or are reasonably likely to have a material impact on our financial condition or results of operations.

Regulatory Assets and Liabilities

Our operations are subject to the provisions of ASC 980, Regulated Operations (ASC 980). Our regulatory assets are the probable future revenues associated with certain costs to be recovered from customers through the ratemaking process, including our estimate of amounts recoverable for natural gas and electric supply purchases. Regulatory liabilities are the probable future reductions in revenues associated with amounts to be credited to customers through the ratemaking process. We determine which costs are recoverable by consulting previous rulings by state regulatory authorities in jurisdictions where we operate or other factors that lead us to believe that cost recovery is probable. This accounting treatment is impacted by the uncertainties of our regulatory environment, anticipated future regulatory decisions and their impact. If any part of our operations becomes no longer subject to the provisions of ASC 980, or facts and circumstances lead us to conclude that a recorded regulatory asset is no longer probable of recovery, we would record a charge to earnings, which could be material. In addition, we would need to determine if there was any impairment to the carrying costs of the associated plant and inventory assets.

While we believe that our assumptions regarding future regulatory actions are reasonable, different assumptions could materially affect our results. See Note 4 - Regulatory Assets and Liabilities, to the Consolidated Financial Statements for further discussion.

Pension and Postretirement Benefit Plans

We sponsor and/or contribute to pension, postretirement health care and life insurance benefits for eligible employees. Our reported costs of providing pension and other postretirement benefits, as described in Note 14 - Employee Benefit Plans, to the Consolidated Financial Statements, are dependent upon numerous factors including the provisions of the plans, changing employee demographics, rate of return on plan assets and other economic conditions, and various actuarial calculations, assumptions, and accounting mechanisms. As a result of these factors, significant portions of pension and other postretirement benefit costs recorded in any period do not reflect (and are generally greater than) the actual benefits provided to plan participants. Due to the complexity of these calculations, the long-term nature of the obligations, and the importance of the assumptions utilized, the determination of these costs is considered a critical accounting estimate.

Assumptions

Key actuarial assumptions utilized in determining these costs include:

•Discount rates used in determining the future benefit obligations;

•Expected long-term rate of return on plan assets; and

•Mortality assumptions.

We review these assumptions on an annual basis and adjust them as necessary. The assumptions are based upon market interest rates, past experience and management's best estimate of future economic conditions.

We set the discount rate using a yield curve analysis, which projects benefit cash flows into the future and then discounts those cash flows to the measurement date using a yield curve. This is done by constructing a hypothetical bond portfolio whose cash flow from coupons and maturities matches the year-by-year projected benefit cash flow from our plans. Based on this analysis as of December 31, 2023, our discount rate on both the NorthWestern Corporation pension plan and NorthWestern Energy pension plan is 4.95-5.00 percent.

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In determining the expected long-term rate of return on plan assets, we review historical returns, the future expectations for returns for each asset class weighted by the target asset allocation of the pension and postretirement portfolios, and long-term inflation assumptions. Our expected long-term rate of return on assets assumptions are 5.15% percent and 6.65% percent on the NorthWestern Corporation and NorthWestern Energy pension plan, respectively, for 2024.

Cost Sensitivity

The following table reflects the sensitivity of pension costs to changes in certain actuarial assumptions (in thousands):

Actuarial AssumptionChange in AssumptionImpact on Pension CostImpact on Projected Benefit Obligation
Discount rate increase0.25%$14$(12,846)
Discount rate decrease(0.25)%1,05913,473
Rate of return on plan assets increase0.25%(1,040)N/A
Rate of return on plan assets decrease(0.25)%1,040N/A

Accounting Treatment

We recognize the funded status of each plan as an asset or liability in the Consolidated Balance Sheets. Differences between actuarial assumptions and actual plan results are deferred and are recognized into earnings only when the accumulated differences exceed 10 percent of the greater of the projected benefit obligation or the market-related value of plan assets, which reduces the volatility of reported pension costs. If necessary, the excess is amortized over the average remaining service period of active employees.

Due to the various regulatory treatments of the plans, our Consolidated Financial Statements reflect the effects of the different rate making principles followed by the jurisdictions regulating us. Pension costs in Montana and other postretirement benefit costs in South Dakota are included in rates on a pay as you go basis for regulatory purposes. Pension costs in South Dakota and other postretirement benefit costs in Montana are included in rates on an accrual basis for regulatory purposes. Regulatory assets have been recognized for the obligations that will be included in future cost of service.

Income Taxes

Judgment and the use of estimates are required in developing the provision for income taxes and reporting of tax-related assets and liabilities. Deferred income tax assets and liabilities represent the future effects on income taxes from temporary differences between the bases of assets and liabilities for financial reporting and tax purposes. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to reverse. The probability of realizing deferred tax assets is based on forecasts of future taxable income and the availability of tax planning strategies that can be implemented, if necessary, to realize deferred tax assets. We establish a valuation allowance when it is more likely than not that all, or a portion of, a deferred tax asset will not be realized. Exposures exist related to various tax filing positions, which may require an extended period of time to resolve and may result in income tax adjustments by taxing authorities. We have reduced deferred tax assets or established liabilities based on our best estimate of future probable adjustments related to these exposures. On a quarterly basis, we evaluate exposures in light of any additional information and make adjustments as necessary to reflect the best estimate of the future outcomes. We believe our deferred tax assets and established liabilities are appropriate for estimated exposures; however, actual results may differ significantly from these estimates.

The interpretation of tax laws involves uncertainty. Ultimate resolution of income tax matters may result in favorable or unfavorable impacts to net income and cash flows and adjustments to tax-related assets and liabilities could be material. The uncertainty and judgment involved in the determination and filing of income taxes is accounted for by prescribing a minimum recognition threshold that a tax position is required to meet before being recognized in the Consolidated Financial Statements. We recognize tax positions that meet the more-likely-than-not threshold as the largest amount of tax benefit that is greater than 50 percent likely of being realized upon ultimate settlement with a taxing authority that has full knowledge of all relevant information. We have unrecognized tax benefits of approximately $28.1 million as of December 31, 2023. The resolution of tax matters in a particular future period could have a material impact on our provision for income taxes, results of operations and our cash flows. See Note 12 - Income Taxes to the Consolidated Financial Statements for further discussion.

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NEW ACCOUNTING STANDARDS

See Note 2 - Significant Accounting Policies, to the Consolidated Financial Statements, included in Item 8 herein for a discussion of new accounting standards.

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