MDU RESOURCES GROUP INC (MDU)

Item 2. Management's Discussion and Analysis of Financial Condition and Results of Operations

The Company generates, transmits and distributes electricity and provides natural gas distribution, transportation and storage services. Through a strategy focusing on its "CORE," the Company strives to deliver superior value and achieve industry-leading performance as a pure-play regulated energy delivery company, while pursuing organic growth opportunities. The Company's "CORE" strategy prioritizes customers and communities, operational excellence, returns focused initiatives and an employee driven culture.

Dividends The Company's board of directors established a long-term dividend payout ratio target of 60 percent to 70 percent of regulated energy delivery earnings. The Company has an 87-year history of uninterrupted dividend payments to stockholders and remains committed to paying a competitive dividend.

Market Trends The Company continues to manage the inflationary pressures experienced throughout the United States, including the impact that inflation, higher interest rates, changes in tariffs, commodity price volatility and supply chain disruptions may have on its business and customers and proactively looks for ways to lessen the impact to its business. The Company has observed supply chain improvements in lead times for certain commodities. The Company has experienced impacts related to the changes in tariffs and continues to navigate the current environment and monitor the future for impacts that could occur. For more information specific to each of the Company's businesses, see the following discussion in each business segment's Outlook section. For more information on the possible impacts, see Part I, Item 1A. Risk Factors in the 2025 Annual Report.

Cautionary Note Regarding Forward-Looking Statements

This Quarterly Report on Form 10-Q contains forward-looking statements within the meaning of the federal securities laws. Other than statements of historical facts, all statements which address activities, events, or developments that the Company anticipates will or may occur in the future are based on underlying assumptions (many of which are based, in turn, upon further assumptions), including, but not limited to, statements identified by the words "anticipates," "estimates," "expects," "intends," "plans," and "predicts," in each case related to such things as growth estimates, stockholder value creation, the Company's "CORE" strategy, capital expenditures, financial guidance, trends, objectives, goals, dividend payout ratio targets, customer rates, regulatory approvals, sustainability, strategies and other such matters, are forward-looking statements. These forward-looking statements are based on many assumptions and factors, which are detailed in the Company's filings with the SEC.

While made in good faith, these forward-looking statements are based largely on the Company's expectations and judgments and are subject to a number of risks and uncertainties, many of which are unforeseeable and beyond the Company's control. For additional discussion regarding risks and uncertainties that may affect forward-looking statements, see Part I, Item 1A. Risk Factors in the 2025 Annual Report and subsequent filings with the SEC. Any changes in such assumptions or factors could produce significantly different results. Undue reliance should not be placed on forward-looking statements, which speak only as of the date they are made. Except as required by applicable law, the Company undertakes no obligation to update the forward-looking statements, whether as a result of new information, future events, or otherwise.

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Consolidated Earnings Overview

The following table summarizes the contribution to the consolidated income by each of the Company's business segments.

Three Months Ended March 31, 2026, Compared to Three Months Ended March 31, 2025 The Company's consolidated earnings decreased $1.2 million. Drivers of the earnings decrease include:

•The electric business earnings decrease was largely the result of higher interest expense associated with debt issuances for recent capital investments including Badger Wind Farm. Lower retail sales volumes due to warmer weather and higher depreciation expense, primarily Badger Wind Farm, further drove the decrease. Higher retail revenues, primarily from recovery mechanisms associated with renewable investments including Badger Wind Farm, largely offset the decrease.

•The natural gas distribution business reported a decrease in earnings, largely the result of lower retail sales volumes due to warmer weather. Lower electric generation transportation volumes driven by warmer weather, higher operation and maintenance expense, primarily payroll-related expense and contract services, and higher interest expense further drove the decrease. The decrease was largely offset by higher retail sales revenue due to rate relief in Washington, Idaho, Montana, and Wyoming.

•The earnings decrease at the pipeline business was driven by lower interruptible natural gas storage withdrawals. Higher operation and maintenance expense primarily attributable to higher materials and payroll-related costs also contributed, as well as higher Montana property tax accruals. The decrease was partially offset by continued strong customer demand for short-term natural gas transportation contracts, as well as impacts from a growth project placed in service in 2025 and a contracted volume increase associated with a previously constructed growth project.

•Other experienced an increase in net income primarily due to income tax adjustments related to the Company's annualized estimated tax rate. Partially offsetting the increase was higher operation and maintenance expense.

A discussion of key financial data from the Company's business segments follows.

Business Segment Financial and Operating Data

The following sections include key financial and operating data for each of the Company's business segments. Also included are highlights on key growth strategies, projections and certain assumptions for the Company and its subsidiaries and other matters of the Company's business segments.

For information pertinent to various commitments and contingencies, see the Condensed Notes to Consolidated Financial Statements. For a summary of the Company's business segments, see Note 14 of the Condensed Notes to Consolidated Financial Statements.

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Electric and Natural Gas Distribution

Strategy and challenges The electric and natural gas distribution segments provide electric and natural gas distribution services to customers, as discussed in Note 14. Both segments strive to be top performing utilities and provide safe, reliable, competitively priced and environmentally responsible energy services to customers. The segments are focused on cultivating organic growth while managing operating costs and monitoring opportunities for these segments to retain, grow and expand their customer base through extensions of existing operations, including building and upgrading electric generation, transmission and distribution, and natural gas systems. The continued efforts to create operational improvements and efficiencies across both segments promotes the Company's business integration strategy. The primary factors that impact the results of these segments are the ability to earn authorized rates of return; weather; climate change laws, regulations and initiatives; competitive factors in the energy industry; population growth; and economic conditions in the segments' service areas.

The electric and natural gas distribution segments are subject to extensive regulation in the jurisdictions where they conduct operations with respect to costs, timely recovery of investments and permitted returns on investment. The Company is focused on modernizing utility infrastructure to meet the varied energy needs of both its customers and communities while working to deliver safe, reliable, affordable and environmentally responsible energy. The segments continue to invest in facility upgrades to be in compliance with existing and known future regulations. To assist in the reduction of regulatory lag in obtaining revenue increases to align with increased investments, tracking mechanisms have been implemented in certain jurisdictions. The Company also seeks rate adjustments for operating costs and capital investments, as well as reasonable returns on investments not covered by tracking mechanisms. For more information on the Company's tracking mechanisms and recent rate cases, see Note 10 and the 2025 Annual Report.

These segments are also subject to extensive regulation related to certain operational and environmental compliance, cybersecurity, permit terms and system integrity. Both segments are faced with the ongoing need to actively evaluate cybersecurity processes and procedures related to its transmission and distribution systems for opportunities to further strengthen its cybersecurity protections. There have been cyber and physical attacks within the energy industry on infrastructure, such as substations, and the Company continues to evaluate the safeguards implemented to protect its electric and natural gas utility systems. Implementation of enhancements and additional requirements to protect the Company's infrastructure is ongoing.

To date, many states have enacted and others are considering, mandatory energy standards requiring utilities to meet certain thresholds of renewable and/or carbon-free energy supply. Over the long-term, the Company expects overall electric demand to be positively impacted by increased electrification trends as a means to address economy-wide carbon emission concerns, large data center growth and changing customer conservation patterns. MISO and NERC announced concerns with reliability of the electric grid due to rapid expansion of renewables and retirement of baseload resources such as coal and the uncertainty of adequate energy production during certain periods of time, while load growth has increased faster than expected due to growth in the data center industry. The Company will continue to monitor the progress of these changes, including the impacts associated with the implementation of MISO's direct loss of load accreditation in 2028, and assess the potential impacts they may have on its stakeholders, business processes, results of operations, cash flows and disclosures.

Revenues are impacted by both customer growth and usage, the latter of which is primarily impacted by weather, as well as impacts associated with commercial and industrial slow-downs, including economic recessions, and energy efficiencies. 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 residential and commercial customers. Average consumption among both electric and natural gas customers has tended to decline as more efficient lighting, appliances, and furnaces are installed, and as the Company has impleme

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Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations

The Company generates, transmits and distributes electricity and provides natural gas distribution, transportation and storage services. Through a strategy focusing on its "CORE," the Company strives to deliver superior value and achieve industry-leading performance as a pure-play regulated energy delivery company, while pursuing organic growth opportunities. The Company's "CORE" strategy prioritizes customers and communities, operational excellence, returns focused initiatives and an employee driven culture.

Strategic Initiatives On May 31, 2023, the Company completed the separation of Knife River, its construction materials and contracting business, resulting in Knife River becoming an independent, publicly-traded company. The Company's board of directors approved the distribution of approximately 90 percent of the issued and outstanding shares of Knife River to the Company's stockholders. Stockholders of the Company received one share of Knife River common stock for every four shares of the Company's common stock held on May 22, 2023, the record date for the distribution. The Company retained approximately 10 percent or 5.7 million shares of Knife River common stock immediately following the separation, which were disposed of in a tax-free exchange in November 2023. The separation of Knife River was a tax-free spinoff transaction to the Company's stockholders for U.S. federal income tax purposes, except for cash received in lieu of fractional shares.

On October 31, 2024, the Company completed the separation of Everus, its construction services business, resulting in Everus becoming an independent, publicly-traded company. The Company's board of directors approved the distribution of all the outstanding shares of Everus common stock to the Company's stockholders. Stockholders of the Company received one share of Everus common stock for every four shares of the Company's common stock held as of the close of business on October 21, 2024, the record date for the distribution. The separation of Everus was a tax-free spinoff transaction to the Company's stockholders for U.S. federal income tax purposes, except for cash received in lieu of fractional shares.

The Company incurred costs in connection with the strategic initiatives in 2023, 2024 and 2025, as noted in the Business Segment Financial and Operating Data section.

One Big Beautiful Bill Act On July 4, 2025, the reconciliation bill was enacted into law, extending key provisions of the 2017 Tax Cuts and Jobs Act while scaling back clean energy tax incentives of the IRA. Changes in tax laws may affect recorded deferred tax assets and deferred tax liabilities or the Company's effective tax rates in the future. The Company has evaluated new legislation, and it does not expect a material impact to the consolidated financial statements or ongoing tax rate as a result of this legislation.

Market Trends The Company continues to manage the inflationary pressures experienced throughout the United States, including the impact that inflation, interest rates, changes in tariffs, commodity price volatility and supply chain disruptions may have on its business and customers and proactively looks for ways to lessen the impact to its business. The Company has observed supply chain improvements in lead times for certain commodities. The Company has experienced impacts related to the changes in tariffs and continues to navigate the current environment and monitor the future for impacts that could occur. For more information on possible impacts to the Company's businesses, see the Outlook for each segment below and Item 1A - Risk Factors.

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Consolidated Earnings Overview

The following table summarizes the contribution to the consolidated income by each of the Company's business segments.

The Company completed the separations of Knife River on May 31, 2023, its former construction materials and contracting segment, and of Everus on October 31, 2024, its former construction services segment, into new independent publicly-traded companies. As a result of these separations, the historical results of operations for Knife River and Everus are shown in discontinued operations, net of tax, except for allocated general corporate overhead costs of the Company, which did not meet the criteria for discontinued operations and are reflected in Other. Also included in discontinued operations are certain strategic initiative costs associated with the separations of Knife River and Everus. Other includes activity for Everus for ten months in 2024 compared to the full year in 2023 and Knife River activity for five months in 2023.

Results of Operations The Company's discussion and analysis for the year ended December 31, 2025 compared to 2024 is included herein. For discussion and analysis for the year ended December 31, 2024 compared to 2023 refer to Part II, Item 7. "Management's Discussion and Analysis of Financial Condition and Results of Operations" in the Company's report on Form 10-K for the year ended December 31, 2024, filed with the SEC on February 20, 2025.

2025 compared to 2024 The Company's consolidated earnings decreased $90.7 million primarily due to the absence of income from discontinued operations in 2025, partially offset by increased earnings at the natural gas distribution business.

•Earnings at the electric business were impacted by higher operation and maintenance expense, primarily increased payroll-related costs, contract services related to Coyote Station planned outage-related costs, software expense, which include certain costs associated with services provided under the Transition Services Agreement with Everus that are recovered in other income, and insurance expense. Partially offsetting the increased operation and maintenance expense were higher retail sales revenue and retail sales volumes, partially driven by a data center near Ellendale, North Dakota.

•Increased earnings at the natural gas distribution business was largely the result of higher retail sales revenue, driven largely by rate relief in Washington, Montana, South Dakota and Wyoming. The increase was partially offset by higher operation and maintenance expense, primarily higher insurance expense, payroll-related costs, and software expense, which include certain costs associated with services provided under the Transition Services Agreement with Everus that are recovered in other income.

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•The pipeline's slight earnings increase was driven by growth projects placed in service throughout 2024 and in late 2025 and customer demand for short-term firm natural gas transportation contracts. Higher use of the company's interruptible natural gas transportation services further drove the increase. The increase was partially offset by higher operation and maintenance expense primarily attributable to payroll-related costs. The increase was further offset by the absence of $1.5 million, net of tax proceeds received in 2024 from a customer settlement as well as the absence of a benefit from an adjustment related to the Company's effective state income tax rate change. The business also incurred higher depreciation expense due to growth projects placed in service, as previously discussed, and higher property taxes in Montana.

•Other was impacted by the absence of the income from discontinued operations in 2025. Partially offsetting the decrease was lower operation and maintenance expense, largely a result of corporate overhead costs classified as continuing operations allocated to the construction services business in 2024, which are not included in Other in 2025.

A discussion of key financial data from the Company's business segments follows.

Business Segment Financial and Operating Data

The following are key financial and operating data for each of the Company's business segments. Highlights of key growth strategies, projections and certain assumptions for the Company and its subsidiaries, and other matters concerning the Company's business segments are included below. Many of these highlighted points are "forward-looking statements." For more information, see Part I - Forward-Looking Statements. There is no assurance that the Company's projections, including estimates for growth and changes in earnings, will in fact be achieved. Please refer to assumptions contained in this section, as well as the various important factors listed in Item 1A - Risk Factors. Changes in such assumptions and factors could cause actual future results to differ materially from the Company's projections.

For information pertinent to various commitments and contingencies, see Item 8 - Notes to Consolidated Financial Statements. For a summary of the Company's business segments, see Item 8 - Note 14.

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Electric and Natural Gas Distribution

Strategy and challenges The electric and natural gas distribution segments provide electric and natural gas distribution services to customers, as discussed in Item 1 - Business. Both segments strive to be top performing utilities and provide safe, reliable, competitively priced and environmentally responsible energy services to customers. The segments are focused on cultivating organic growth while managing operating costs and monitoring opportunities for these segments to retain, grow and expand their customer base through extensions of existing operations, including building and upgrading electric generation, transmission and distribution, and natural gas systems. The continued efforts to create operational improvements and efficiencies across both segments promotes the Company's business integration strategy. The primary factors that impact the results of these segments are the ability to earn authorized rates of return; weather; climate change laws, regulations and initiatives; competitive factors in the energy industry; population growth; and economic conditions in the segments' service areas.

The electric and natural gas distribution segments are subject to extensive regulation in the jurisdictions where they conduct operations with respect to costs, timely recovery of investments and permitted returns on investment. The Company is focused on modernizing utility infrastructure to meet the varied energy needs of both its customers and communities while working to deliver safe, reliable, affordable and environmentally responsible energy. The segments continue to invest in facility upgrades to be in compliance with existing and known future regulations. To assist in the reduction of regulatory lag in obtaining revenue increases to align with increased investments, tracking mechanisms have been implemented in certain jurisdictions. The Company also seeks rate adjustments for operating costs and capital investments, as well as reasonable returns on investments not covered by tracking mechanisms. For more information on the Company's tracking mechanisms and recent rate cases, see Item 1 - Business and Item 8 - Note 6.

These segments are also subject to extensive regulation related to certain operational and environmental compliance, cybersecurity, permit terms and system integrity. Both segments are faced with the ongoing need to actively evaluate cybersecurity processes and procedures related to its transmission and distribution systems for opportunities to further strengthen its cybersecurity protections. There have been cyber and physical attacks within the energy industry on infrastructure, such as substations, and the Company continues to evaluate the safeguards implemented to protect its electric and natural gas utility systems. Implementation of enhancements and additional requirements to protect the Company's infrastructure is ongoing.

To date, many states have enacted, and others are considering, mandatory energy standards requiring utilities to meet certain thresholds of renewable and/or carbon-free energy supply. Over the long-term, the Company expects overall electric demand to be positively impacted by increased electrification trends as a means to address economy-wide carbon emission concerns, large data center growth and changing customer conservation patterns. MISO and NERC announced concerns with reliability of the electric grid due to rapid expansion of renewables and retirement of baseload resources such as coal and the uncertainty of adequate energy production during certain periods of time, while load growth has increased faster than expected due to growth in the data center industry. Montana-Dakota filed its 2024 IRP with the NDPSC in July 2024. With MISO's filed changes in resources adequacy at FERC and the adoption of direct loss of load accreditation for generation resources around riskiest hours on the system versus peak load hours, Montana-Dakota identified the need to add additional capacity resources to its system by 2028 versus 2034 as identified in its previous IRP. The Company previously executed a PPA for 150 MW of output from Badger Wind Farm, which included the option to purchase a 49 percent ownership interest. With the closing now complete, the PPA has been reduced to 27.5 MW. The ownership stake in Badger Wind Farm reduced the Company's capacity and energy purchase requirements as identified in the 2024 IRP. The Company will continue to monitor the progress of these changes, including the impacts associated with the implementation of MISO's direct loss of load accreditation in 2028, and assess the potential impacts they may have on its stakeholders, business processes, results of operations, cash flows and disclosures.

Revenues are impacted by both customer growth and usage, the latter of which is primarily impacted by weather, as well as impacts associated with commercial and industrial slow-downs, including economic recessions, and energy efficiencies. 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 residential and commercial customers. Average consumption among both electric and natural gas customers has tended to decline as more efficient appliances and furnaces are installed, and as the Company has implemented conservation programs. Natural gas weather normalization and decoupling mechanisms in certain jurisdictions have been implemented to largely mitigate the effect that would otherwise be caused by variations in volumes sold to these customers due to weather and changing consumption patterns on the Company's distribution margins, as further discussed in Item 1 - Business.

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In the second half of 2023, electric fuel and purchased power prices increased across Montana-Dakota's integrated system and remained elevated through January 2024. This was caused by transmission congestion in northwest North Dakota due to delays in additional SPP transmission line build-out, as well as additional load growth in the Bakken region. To assist in the recovery of the higher electric fuel and purchased power costs, Montana-Dakota filed waiver requests with the NDPSC and SDPUC, deferring the increased costs to the annual fuel clause adjustment. In Montana, the waiver request is filed monthly and was unopposed by the MTPSC. Effective April 1, 2024, as approved by the NDPSC, Montana-Dakota started recovery in North Dakota of these increased costs over a period of two years rather than one year. In South Dakota and Montana, Montana-Dakota recovered these costs over a one-year period effective July 1, 2024. In July 2025, the NDPSC approved Montana-Dakota's request to defer external legal expenses related to this congestion litigation and record those deferred expenses into a regulatory asset. Montana-Dakota and MISO each filed a petition for review of the FERC decision with the Eighth Circuit with a decision expected in the first half of 2026.

The Company continues to proactively monitor and work with its manufacturers to reduce the effects of increased pricing and lead times on delivery of certain raw materials and equipment used in electric generation, transmission and distribution system and natural gas pipeline projects. Long lead times are attributable to increased demand for steel products from pipeline companies as they continue pipeline system safety and integrity replacement projects driven by PHMSA regulations, as well as delays in the manufacturing and shipping of electrical equipment and increased demand for electrical equipment due to regulatory activity and grid expansion. The Company has been able to minimize the effects by working closely with suppliers or obtaining additional suppliers, as well as modifying project plans to accommodate extended lead times and increased costs. The Company expects these delays to continue. Inflationary pressures have moderated but costs for goods and services remain high. The Company also continues to monitor the impact tariffs will have on its costs. Tariff increases on raw materials could negatively affect the Company's construction projects and maintenance work. For additional discussion regarding risks and uncertainties, see Item 1A - Risk Factors.

The ability to grow through acquisitions is subject to significant competition and acquisition premiums. In addition, the ability of the segments to grow their service territory and customer base is affected by regulatory constraints, the economic environment of the markets served, population changes and competition from other energy providers and fuel. The construction of new electric generating facilities, transmission lines and other service facilities is subject to higher costs and long lead times for equipment, extensive permitting procedures, and federal and state legislative and regulatory initiatives, which may necessitate increases in electric energy prices. As the industry continues to expand the use of renewable energy sources, the need for additional transmission infrastructure is growing. As part of MISO's long range transmission plan, in August 2022, the Company announced its intent to develop, construct and co-own JETx with Otter Tail Power Company in central North Dakota. In October 2023, the FERC issued an order approving the Company's request for CWIP Incentive Rate and Abandoned Plant Incentive treatment on this project. Montana-Dakota and Otter Tail Power Company received approval of a Certificate of Public Convenience and Necessity from the NDPSC in November 2024 on this project. The route permit for the JETx line was filed with the NDPSC in August 2025. JETx is expected to be placed in service at the end of 2028.

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Earnings overview - The following information summarizes the performance of the electric segment.

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2025 compared to 2024 Electric earnings decreased $9.9 million as a result of:

•Revenue increased $23.8 million.

◦Largely attributable to:

▪Higher fuel and purchased power costs of $17.8 million recovered in customer rates and offset in expense, as described below.

▪Higher net transmission revenue of $3.5 million, including data center revenue.

▪Higher retail sales volumes of $1.2 million, driven primarily by higher residential volumes, largely due to colder weather in the first quarter of the year, and higher commercial volumes from the data center as further discussed in the Outlook section.

◦Partially offset by lower renewable tracker revenues, partially associated with higher production tax credits offset in income tax benefit, as described below.

•Electric fuel and purchased power increased $17.8 million, largely the result of higher retail sales volumes and higher commodity prices.

•Operation and maintenance increased $16.3 million.

◦Largely the result of:

▪Higher payroll-related costs of $5.7 million.

▪Higher contract services related to Coyote generating station planned outage-related costs of $3.5 million.

▪Increased software expense of $3.2 million.

▪Higher insurance expense.

◦Also reflected are higher costs associated with services provided to Everus as part of the transition services agreement, offset in other income, as described below. The transition services are expected to be complete as of March 2026.

•Depreciation and amortization increased $3.1 million, largely due to increased property, plant and equipment balances, as a result of transmission projects placed in service to improve reliability and update aging infrastructure.

•Taxes, other than income increased $1.2 million, largely as a result of higher property tax, primarily in Montana.

•Other income decreased $800,000, primarily due to lower interest income related to a data center project and lower regulatory deferral balances, partially offset by higher transition services agreement income, as described above.

•Interest expense increased $1.7 million, largely the result of lower AFUDC due to lower interest rates and average CWIP balances.

•Income tax benefit increased $7.2 million, largely due to lower income before income taxes, and higher production tax credits of $2.5 million driven by higher wind production and wind farm repowers.

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Earnings overview - The following information summarizes the performance of the natural gas distribution segment.

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2025 compared to 2024: Natural gas distribution earnings increased $9.2 million as a result of:

•Revenue increased $82.4 million.

◦Primarily due to:

▪Higher purchased natural gas sold of $47.0 million, including net environmental compliance costs, recovered in customer rates and offset in expense, as described below.

▪Rate relief of $25.2 million, primarily in Washington, Montana, South Dakota and Wyoming.

▪Higher revenue-based taxes of $3.6 million, recovered in rates and offset in expense, as described below.

▪Higher conservation revenues of $3.5 million, offset in expense, as described below.

▪Higher basic service charges of $2.1 million due to customer growth.

▪Higher retail sales volumes of $2.0 million, which includes weather normalization and decoupling mechanism in certain jurisdictions, and higher volumes to commercial customer classes. This increase was largely offset by lower volumes to residential customer classes, largely due to warmer weather in certain jurisdictions.

•Purchased natural gas sold increased $47.0 million, primarily due to higher net environmental compliance costs of $38.1 million, commodity costs of $4.9 million and volumes of natural gas purchased of $4.0 million.

•Operation and maintenance increased $10.0 million.

◦ Largely due to:

▪Higher conservation-related costs, recovered in rates, as discussed above.

▪Higher costs associated with MAOP projects of $1.7 million.

▪Higher insurance expense.

▪Higher payroll-related costs of $1.5 million.

▪Higher software related expenses of $1.3 million.

◦Also reflected are higher costs associated with services provided to Everus as part of the transition services agreement, offset in other income, as described below. The transition services are expected to be complete as of March 2026.

•Depreciation and amortization increased $3.0 million, of which $6.6 million resulted from increased property, plant and equipment balances related to growth and replacement projects placed in service, partially offset by lower depreciation rates implemented from rate cases in Montana, North Dakota, Wyoming, Washington and Oregon of $2.9 million, and lower regulatory amortizations.

•Taxes, other than income increased $5.5 million, due to higher revenue-based taxes, as described above, and higher property taxes, largely in Montana and Washington.

•Other income decreased $9.7 million.

◦Primarily due to:

▪Lower interest on regulatory deferral balances, primarily lower purchased gas cost deferral balances.

▪The absence of $2.2 million of interest income associated with prior year renewable natural gas projects.

▪Higher pension expense of $1.4 million.

▪Lower returns of $500,000 on the Company's nonqualified benefit plans.

◦Offset in part by higher transition services agreement income, as described above.

•Interest expense decreased $3.6 million, largely due to lower long-term debt balances.

•Income tax expense increased $1.6 million, largely the result of higher income before income taxes, partially offset by lower permanent tax adjustments.

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Outlook In 2025, the utility business experienced rate base growth of 16.0 percent, which includes the purchase of its ownership stake in Badger Wind Farm. These segments grew rate base by 8.7 percent annually over the last five years on a compound basis and expects to invest approximately $2.5 billion of capital expenditures over the next five years. Operations are spread across eight states where the Company expects customer growth to be higher than the national average. In 2025 and 2024, these segments experienced retail customer growth of approximately 1.5 percent and 1.4 percent, respectively, and the Company expects customer growth to continue to average 1 percent to 2 percent per year. This customer growth, along with system upgrades and replacements needed to supply safe and reliable service, will require investments in new and replacement electric and natural gas systems.

These segments are exposed to energy price volatility and may be impacted by changes in oil and natural gas exploration and production activity. Rate schedules in the jurisdictions in which the Company's natural gas distribution segment operates contain clauses that permit the Company to file for rate adjustments for changes in the cost of purchased natural gas. Although changes in the price of natural gas are passed through to customers and have minimal impact on the Company's earnings, the natural gas distribution segment's customers may benefit through the Company's utilization of storage and fixed price contracts to help manage price volatility.

The EPA's GHG and mercury emissions standards finalized in May 2024 would have required additional pollution controls for Coyote Station to operate beyond 2031 and 2027, respectively. In April 2025, the EPA granted a two year extension for Coyote Station to add pollution controls to comply with the mercury emissions standard. In June 2025, the EPA proposed rules to repeal both the mercury emissions standard and the electric generation GHG emissions standard. If the rules go into effect, it could require owners of Coyote station to incur significant new costs. These costs could, dependent on determination by state regulatory commissions on approval to recover such costs from customers, negatively impact the Company's results of operations, financial position and cash flows. In December 2024, the EPA issued a final decision on the NDDEQ's Regional Haze state implementation plan, maintaining the proposed disapproval of the state's conclusion that no additional controls are warranted during this implementation period. The EPA did not issue a federal implementation plan in place of the state plan and would have two years from the state plan disapproval to either propose a federal plan or approve a new state plan. Coyote Station co-owners filed a petition for review with the Eighth Circuit in January 2025, challenging EPA's NDDEQ state plan disapproval, and in February 2025, filed a petition for reconsideration with the EPA, which was granted in April 2025. In June 2025, the Eighth Circuit granted a request by the EPA to continue to hold the petition of review proceeding in abeyance so that the EPA could review the previous administration's findings and actions. In March 2025, the EPA announced the agency is restructuring the regulations for implementing the Regional Haze Program. Further, in October 2025, the EPA released an advanced notice of proposed rulemaking seeking input on restructuring the program with the intent to streamline regulatory requirements for states' visibility improvement obligations. The Company is one of four owners of Coyote Station and cannot make a unilateral decision on the plant's future; therefore, the Company could be negatively impacted by decisions of the other owners. The joint owners continue to collaborate in analyzing data and weighing decisions that impact the plant and its employees as well as each company's customers and communities served.

In December 2025, the Company completed the acquisition of a 49 percent ownership interest in Badger Wind Farm and placed the asset in service. The completed transaction secures 122.5 MW of the project's total 250 MW generation capacity for the Company and follows the NDPSC's Advance Determination of Prudence and Certificate of Public Convenience and Necessity approvals, confirming the project is a prudent, cost-effective investment for customers. The Company previously executed a PPA for 150 MW of output from the project, which included the option to purchase the 49 percent ownership interest. With the closing now complete, the PPA has been reduced to 27.5 MW.

In March 2023, the Company began to provide power for Applied Digital's data center near Ellendale, North Dakota. At full capacity, the data center requires 180 MW of electricity, which is the equivalent of about 21 percent of the Company's generation portfolio. Applied Digital's load is purchased from the MISO market and does not impact other customers' power supply. An electric service agreement to serve an additional 350 MW data center load with Applied Digital in the Company's service territory was approved by the NDPSC. 100 MW of the additional data center load is expected to be fully online in the second quarter of 2026.

In August 2024, the Company filed a request with the SDPUC seeking approval on an electric service agreement to provide up to 50 MW of electricity to a data center near Leola, South Dakota. Construction of the data center and approval of the electric service agreement which had been pending development of new local siting requirements for data center loads by McPherson County in South Dakota, were effective August 5, 2025. Approval of the electric service agreement with the SDPUC is still pending filing an updated conditional use permit for the data center siting with McPherson County.

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The Infrastructure Investment and Jobs Act, commonly known as the Bipartisan Infrastructure Law, was enacted in the fourth quarter of 2021 designating funds for investments such as upgrades to electric and grid infrastructure, transportation systems, and electric vehicle infrastructure. In July 2025, the North Dakota Industrial Commission awarded the Company a grant award under the Grid Resilience and Innovative Partnerships Program, which is part of the Infrastructure Investment and Jobs Act. The funds from the award will be used by the Company to build a 46 kV transmission line that will connect the Merricourt Transmission Substation to a 46 kV line near Fredonia, North Dakota. In addition, the IRA provided new funding for clean energy programs. The Company continues to pursue various opportunities under the Grid Resilience and Innovative Partnerships Program, and is also pursuing a biogas property at the Knott Landfill site in Bend, Oregon which may qualify for an investment tax credit and clean fuel production credits as part of the IRA. As discussed previously, the Company has evaluated the OBBBA and does not expect a material impact as a result of this legislation.

Legislation and rulemaking The Company continues to monitor legislation and rulemaking related to clean energy standards that may impact its segments. Below are some of the specific legislative actions the Company is monitoring.

•In May 2024, the EPA published four final rules, three of which will impose stricter standards on GHG emissions from existing coal-fired and new natural gas-fired generation units, require a further reduction of mercury emissions from coal-fired generation units, and impose additional regulations around the storage and management of coal ash. In March 2025, the EPA announced reconsideration of the Electric Generation and Greenhouse Gas Rule, Mercury and Air Toxics Standards Rule, and Effluent Limitations Guidelines Rule. Comments on certain of these proposed rules were due in August 2025. If the rules were to remain as originally proposed and if the costs to comply with these rules are not fully recoverable from customers, they could have a material adverse effect on the Company's results of operations and cash flows.

•In February 2026, the EPA published a final rule that rescinded the 2009 Endangerment Finding and related standards for motor vehicle GHG emissions under the Clean Air Act. The final rule does not directly address or repeal GHG regulations for power plants and other non-motor vehicle sources. The Company is currently evaluating this rulemaking.

•In July 2024, the ODEQ published its proposed rules to create a new Climate Protection Program. The Oregon Environmental Quality Commission adopted the rules in November 2024. The Company intends to meet its obligations first through no-cost emissions allowances and will fill remaining compliance obligations by investing in additional customer conservation and energy efficiency programs, purchasing community climate investment credits, and acquiring environmental attributes from low-carbon fuel projects such as RNG. Compliance costs for these regulations are being recovered through customer rates. Due to the timing of regulatory recovery, future compliance obligation purchases could impact the Company's operating cash flow.

•In Washington, the Climate Commitment Act was adopted by the Washington Legislature in 2021 and became effective in 2023. The Climate Commitment Act establishes a cap-and-invest program designed to reduce GHG emissions over time, while using auctioned allowances to fund state energy and environmental policy goals. The Company intends to meet its compliance obligations through a combination of energy efficiency measures, no-cost allowances, purchased allowances, and carbon offsets. Compliance costs for these regulations are being recovered through customer rates. Due to the timing of regulatory recovery, the purchase of allowances could impact the Company's operating cash flow.

•The Washington SBCC in 2023 adopted residential and commercial building code amendments that will significantly limit the use of natural gas for space and water heating in new and retrofitted commercial and residential buildings. In May 2024, the Company filed a joint complaint seeking declaratory and injunctive relief under federal law against the Washington SBCC's adoption of the amended Washington State Energy Code. This complaint was dismissed by the federal district court. Petitioners have appealed this decision to the United States Court of Appeals for the Ninth Circuit. The Company's opening brief was filed in July 2025. Oral argument before a three-judge panel of the Ninth Circuit was held on February 10, 2026.

Initiative Measure No. 2066, which was approved by voters, does not allow the Washington State Energy Code to "in any way prohibit, penalize, or discourage the use of gas for any form of heating, or for uses related to any appliance or equipment, in any building." In May 2025, the King County Superior Court filed an order ruling Initiative Measure No. 2066 unconstitutional. Following the ruling, the Building Industry Association of Washington filed a notice of appeal with the King County Superior Court. The King County Superior Court’s order invalidating Initiative Measure No. 2066 is now pending review by the Washington State Supreme Court. The Court heard oral arguments in the case in January 2026.

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•In March 2024, the SEC issued Final Rule 33-11275 - The Enhancement and Standardization of Climate-Related Disclosures for Investors. In April 2024, the SEC announced that it would voluntarily stay its final climate disclosure rules pending judicial review. In March 2025, the SEC withdrew its defense of the rules. In July 2025, the SEC asked the Eighth Circuit to issue a ruling on the abandoned climate regulations. In September 2025, the Eighth Circuit stated it was pausing its consideration of legal challenges against this rule, pending further action by the SEC.

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Pipeline

Strategy and challenges The pipeline segment provides natural gas transportation, underground storage and energy-related services, including cathodic protection, as discussed in Item 1 - Business. The segment focuses on utilizing its extensive expertise in the design, construction and operation of energy infrastructure and related services to increase market share and profitability through optimization of existing operations, organic growth and investments in energy-related assets within or in close proximity to its current operating areas. The segment focuses on the continual safety and reliability of its systems, which entails building, operating and maintaining safe natural gas pipelines and facilities. The segment continues to evaluate growth opportunities including the expansion of natural gas facilities; incremental pipeline projects; and expansion of energy-related services leveraging on its core competencies. In support of this strategy, the Company completed the following growth projects in 2024 and 2025:

•In March 2024, the 2023 Line Section 27 Expansion project was placed in service and increased system capacity by 175 MMcf of natural gas per day.

•In July 2024, the Line Section 28 Expansion project was placed in service and increased system capacity by 137 MMcf of natural gas per day.

•In November 2024, the Company closed on the purchase of a 28-mile natural gas pipeline lateral in northwestern North Dakota.

•In December 2024, the Wahpeton Expansion project was placed in service and increased system capacity by approximately 20 MMcf of natural gas per day.

•In November 2025, the Minot Expansion Project was placed in service and increased system capacity by 7 MMcf of natural gas per day.

The segment is exposed to natural gas and oil price volatility including fluctuations in basis differentials. Legislative and regulatory initiatives on increased pipeline safety regulations and environmental matters such as the reduction of methane emissions could also impact the price and demand for natural gas.

The pipeline segment is subject to extensive regulation related to certain operational and environmental compliance, cybersecurity, permit terms and system integrity. The Company continues to actively evaluate cybersecurity processes and procedures, including changes in the industry's cybersecurity regulations, for opportunities to further strengthen its cybersecurity protections. Implementation of enhancements and additional requirements is ongoing. The segment reviews and secures existing permits and easements, as well as new permits and easements as necessary, to meet current demand and future growth opportunities on an ongoing basis.

Tariff increases on raw materials could negatively affect the Company's construction projects and maintenance work. The Company continues to monitor the impact tariffs will have on its costs. The Company continues to actively manage the national supply chain challenges by working with its manufacturers and suppliers to help mitigate some of these risks on its business. The segment regularly experiences extended lead times on raw materials that are critical to the segment's construction and maintenance work which could delay maintenance work and construction projects potentially causing lost revenues and/or increased costs. The Company is partially mitigating these challenges by planning for extended lead times further in advance. The Company expects these delays to continue. Inflationary pressures have moderated, but costs for raw material and contract services remain high. For additional discussion regarding risks and uncertainties, see Item 1A - Risk Factors.

The segment focuses on the recruitment and retention of a skilled workforce to remain competitive and provide services to its customers. The industry in which it operates relies on a skilled workforce to construct energy infrastructure and operate existing infrastructure in a safe manner. A shortage of skilled personnel can create a competitive labor market which could increase costs incurred by the segment. Competition from other pipeline companies can also have a negative impact on the segment.

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Earnings overview - The following information summarizes the performance of the pipeline segment.

2025 compared to 2024 Pipeline earnings increased $200,000 as a result of:

•Revenues increased $17.4 million.

◦Increased demand revenue, largely due to:

▪Growth projects placed in service throughout 2024 and in late 2025 of $11.1 million.

▪Increased usage of short-term firm natural gas transportation contracts of $5.7 million.

▪Partially offset by the expiration of certain contracts.

◦Higher interruptible transportation revenue of $1.3 million.

◦Higher non-regulated project revenue of $800,000.

•Operation and maintenance increased $6.1 million.

◦Primarily due to:

▪Higher payroll-related costs of $2.3 million.

▪Higher non-regulated project costs, associated with increased non-regulated project revenue as previously discussed.

▪Also reflected are higher costs associated with services provided to Everus as part of transition services agreement, offset in other income, as described below. The transition services are expected to be complete as of March 2026.

▪Higher contract services of $600,000, auto of $500,000 and insurance costs of $400,000.

•Depreciation and amortization increased $2.7 million due to higher property, plant and equipment balances associated with growth projects placed in-service, as previously discussed, partially offset by fully depreciated assets.

•Taxes, other than income increased $2.0 million, largely resulting from higher property taxes in Montana.

•Other income decreased $2.8 million.

◦Primarily due to:

▪The absence of proceeds received in 2024 from a customer settlement of $2.0 million.

▪Lower AFUDC for the construction of the company's growth projects.

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◦Partially offset by higher transition services agreement income, as described above.

•Interest expense increased $1.2 million, resulting from higher debt balances to fund capital expenditures, as previously discussed, and lower AFUDC, as previously discussed.

•Income tax expense increased $2.4 million, largely due to the absence of a benefit from an adjustment related to the Company's effective state income tax rate change.

Outlook The Company has continued to experience the effect of associated natural gas production in the Bakken, which has provided opportunities for organic growth projects and increased transportation demand. The completion of organic growth projects has contributed to higher volumes of natural gas the Company transports through its system. Bakken natural gas production is currently at or near record levels and the outlook remains positive with continued growth expected due to increasing gas to oil ratios which may moderate recent decreases in drilling activity.

Increases in national and global natural gas supply have moderated pressure on natural gas prices and price volatility. While the Company believes there will continue to be varying pressures on natural gas production levels and prices, the long-term outlook for natural gas prices continues to provide growth opportunity for industrial supply and demand related projects and seasonal pricing differentials provide opportunities for natural gas storage services.

The Company continues to monitor, evaluate and implement additional GHG emissions reduction strategies, including increased monitoring frequency and emission source control technologies to minimize potential risk.

GHG emissions regulations continue to evolve due to congressional actions and agency reconsideration. Methane Waste Emissions Charge regulations finalized in 2024 were eliminated by a resolution of disapproval passed by Congress and signed by the President in March 2025. The OBBBA postponed the Waste Emissions Charge provisions in the Clean Air Act to 2034. The EPA has issued several actions since the EPA Administrator's announcement regarding 31 historic actions to advance the President's "Power the Great American Comeback", which include extending deadlines for certain oil and gas new source performance standards and a proposal to reconsider the Greenhouse Gas Reporting Program. The Company continues to comply with rules as they remain in effect, and to monitor and assess these rulemaking changes and the potential impacts they may have on its business processes, current and future projects, results of operations and disclosures.

The Company continues to focus on improving existing operations and growth opportunities through organic projects in all areas in which it operates, which includes additional projects supporting the needs of local distribution companies, Bakken area producers, electric generation customers and industrial customers in various stages of development, including:

•Line Section 32 Expansion Project which will provide natural gas transportation service to a new electric generation facility in northwest North Dakota. The project consists of approximately 20 miles of pipe and ancillary facilities and is designed to increase natural gas transportation capacity by 190 MMcf per day, which is supported by a long-term customer agreement. The Company continues to make progress on required surveys and anticipates filing its FERC application in March 2026. The project is dependent on regulatory approvals and is targeted to be in service in late 2028.

•Potential Bakken East Pipeline Project, which could consist of 350 miles of pipeline construction from western North Dakota to the eastern part of the state, plus additional pipeline laterals. The Company continues actively marketing the project and began a binding open season on February 2, 2026, which will conclude on March 13, 2026. The results of the open season will be evaluated to determine the final design, timeline and project cost. In 2025, the Company began working with landowners to conduct environmental and civil surveys along the potential route and plans to continue survey work in the spring of 2026 when weather conditions allow. In August 2025, the North Dakota Industrial Commission selected the project for firm capacity commitments of up to $50 million annually for 10 years.

•Potential Minot Industrial Pipeline Project, which could consist of an approximately 90-mile pipeline from Tioga, North Dakota to Minot, North Dakota and ancillary facilities. The Company has signed an agreement to support the early stage development of the project through the second quarter of 2026. The project would provide incremental natural gas transportation capacity for anticipated industrial demand.

See Capital Expenditures within this section for information on the expenditures related to these growth projects.

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Other

The Company completed the separations of Knife River, its former construction materials and contracting segment, on May 31, 2023 and Everus, its former construction services segment, on October 31, 2024, into new independent publicly-traded companies. As a result of these separations, the historical results of operations for Knife River and Everus are shown in discontinued operations, net of tax, except for allocated general corporate overhead costs of the Company, which did not meet the criteria for discontinued operations and are reflected in Other. Also included in discontinued operations are certain strategic initiative costs associated with the separations of Knife River and Everus. Other includes activity for Everus for ten months in 2024 compared to the full year in 2023 and Knife River activity for five months in 2023, as well as corporate overhead costs paid by Everus and Knife River for those respective periods which were allocated to the Company's remaining segments in 2025.

Also included in Other is insurance activity at the Company's captive insurer and general and administrative costs and interest expense previously allocated to the exploration and production and refining businesses that did not meet the criteria for discontinued operations.

For the full year, Other reported net income of $1.2 million compared to net income of $91.4 million for 2024. The decrease was primarily due to the absence of the income from discontinued operations in 2025. Partially offsetting the decrease was lower operation and maintenance expense, largely a result of corporate overhead costs classified as continuing operations allocated to the construction services business in 2024, which were allocated to the Company's remaining segments in 2025.

Intersegment Transactions

Amounts presented in the preceding tables will not agree with the Consolidated Statements of Income due to the Company's elimination of intersegment transactions. The amounts related to these items were as follows:

For more information on intersegment eliminations, see Item 8 - Note 14.

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Liquidity and Capital Commitments

At December 31, 2025, the Company had cash, cash equivalents and restricted cash of $28.2 million and available borrowing capacity of $418.1 million under the outstanding credit facilities of the Company and its subsidiaries. The Company expects to meet its obligations for debt maturing within one year and its other operating and capital requirements from various sources, including internally generated funds; credit facilities and commercial paper of the Company and its subsidiaries, as described in Capital resources; and issuance of debt securities and equity securities using the Company's FSA and ATM program as needed.

Cash flows

Operating activities

The changes in cash flows from operating activities generally follow the results of operations as discussed in Business Segment Financial and Operating Data and are affected by changes in working capital.

The decrease in cash flows provided by operating activities in 2025 from 2024 was largely driven by the absence of cash provided by discontinued operations in 2024, as well as the absence of certain fuel cost recoveries in 2025 and increases in certain regulatory cost deferrals. Partially offsetting the decrease was higher collection of accounts receivable associated with higher gas costs in December 2024, lower cash used for payment of other current liabilities, including compliance costs, accrued compensation, data center customer deposits, and net environmental compliance costs, all at the natural gas distribution business.

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Investing activities

The increase in cash used in investing activities in 2025 from 2024 was primarily due to higher capital expenditures at the electric business, largely related to the Badger Wind Farm, partially offset by lower capital expenditures at the pipeline business due to the absence of the 2024 Wahpeton Expansion project. Partially offsetting this was the absence of cash used in discontinued operations with the spinoff of Everus.

Financing activities

The increase in cash provided by financing activities in 2025 from 2024 was primarily due higher long-term debt issuance proceeds used to finance capital expenditure projects, primarily at the electric business. Also contributing was the absence of 2024 short-term borrowing repayment at the natural gas distribution business. Partially offsetting these items was the absence of cash provided by discontinued operations in 2024.

Defined benefit pension plans

The Company has noncontributory qualified defined benefit pension plans for certain employees. Plan assets consist of investments in equity and fixed-income securities. Various actuarial assumptions are used in calculating the benefit expense (income) and liability (asset) related to the pension plans. Actuarial assumptions include assumptions about the discount rate and expected return on plan assets. For 2025, the Company assumed a long-term rate of return on its qualified defined pension plan assets of 6.5 percent. Differences between actuarial assumptions and actual plan results are deferred and amortized into expense when the accumulated differences exceed 10 percent of the greater of the projected benefit obligation or the market-related value of plan assets. Therefore, this change in asset values will be reflected in future expenses of the plans beginning in 2026. The funded status of the plans improved $6.3 million from prior year, primarily due to increase in plan assets, as discussed previously.

At December 31, 2025, the pension plans' projected benefit obligations exceeded these plans' assets by approximately $18.5 million. Pretax pension expense reflected in the Consolidated Statements of Income for the years ended

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December 31, 2025 and 2024, was $3.4 million and $835,000, respectively. Pretax pension income reflected in the Consolidated Statements of Income for the year ended December 31, 2023 was $580,000. The Company's pension expense is currently projected to be approximately $4.7 million in 2026. Funding for the pension plans is actuarially determined. The Company expects to contribute the minimum funding requirement of $3.8 million in 2026. For the years ended December 31, 2025 and 2024, the Company contributed the minimum funding requirement of $3.4 million and $2.9 million, respectively. There were no minimum required contributions for the year ended December 31, 2023, due to an additional contribution of $20.0 million in 2019, which created prefunding credits that were used in future periods. For more information on the Company's pension plans, see Item 8 - Note 15.

Capital expenditures

The Company's capital expenditures, excluding discontinued operations, for 2023 through 2025 and as anticipated for 2026 through 2028 are summarized in the following table.

(a)Capital expenditures for 2023 are reported as gross capital expenditures. Capital expenditures for 2024 and 2025 as well as estimated expenditures for 2026 through 2028 are reported on a net basis.

(b)Capital expenditures for 2023, 2024 and 2025 include noncash transactions such as capital expenditure-related accounts payable and AFUDC totaling $(13.6) million, $7.1 million, and $(10.8) million, respectively.

(c)2025 capital expenditures were funded by cash provided from operating activities, long-term debt issuances and borrowings under credit facilities and issuance of commercial paper of the Company and its subsidiaries.

(d)The Company completed the final $264.6 million payment for a 49 percent ownership interest in Badger Wind Farm, which was acquired and placed in service on December 31, 2025. This amount was previously included in 2026 estimates.

(e)Excludes Other category.

Planned utility investments in the Company's estimated capital expenditures for 2026 through 2028 include system upgrades, substation improvements and generation projects, construction of JETx, system replacements, expansion and modernization projects to meet demand from a growing customer base, including new service extensions and capacity expansion to accommodate economic and population growth across the Company's eight-state territory. The pipeline business will continue to evaluate customer-driven projects, including expansion projects, to serve power generation and industrial demand in the region. In addition, the pipeline will focus on system maintenance and expanding capacity where market conditions support additional investment. A number of projects are included in the planned investments as the Company continues to invest in safe, reliable and environmentally-responsible energy delivery infrastructure across its regulated businesses. For more information on the Company's growth projects, see Business Segment Financial and Operating Data.

The Company continues to evaluate potential future acquisitions and other growth opportunities that would be incremental to the outlined capital program; however, they are dependent upon the availability of economic opportunities and, as a result, capital expenditures may vary significantly from the estimates in the preceding table. The Company continuously monitors its capital expenditures for project delays and changes in economic viability and adjusts as necessary. It is anticipated that all of the funds required for capital expenditures for the years 2026 through 2028 will be funded by various sources, including equity issuance, debt financing and internally generated funds.

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Capital resources

The Company requires significant cash to support and grow its businesses. The primary sources of cash other than cash generated from operating activities are cash from revolving credit facilities, the issuance of long-term debt and the sale of equity securities.

Debt resources Certain debt instruments of the Company and its subsidiaries contain restrictive and financial covenants and cross-default provisions. In order to borrow under the respective debt agreements, the Company and its subsidiaries must be in compliance with the applicable covenants and certain other conditions. Intermountain was not in compliance with its minimum interest coverage ratio for the period ended September 30, 2025, which constituted an event of default under the terms of the Intermountain NPAs. In addition, the event of default under the terms of the Intermountain NPAs constituted a cross-default under the terms of certain NPAs of MDU Energy Capital and revolving credit agreements held by the Company and Intermountain. Subsequent to September 30, 2025, Intermountain and MDU Energy Capital obtained waivers for this non-compliance from the holders of a majority of their respective outstanding notes, and Intermountain and the Company obtained waivers from the lenders of the revolving credit agreements, which collectively cured the impact of any events of default. The Company and its subsidiaries were in compliance with applicable covenants at December 31, 2025. In the event the Company or its subsidiaries do not comply with the applicable covenants and other conditions, alternative sources of funding may need to be pursued. As of December 31, 2025, the Company had investment grade credit ratings at all entities issuing debt which carried public ratings. For more information on the covenants, certain other conditions and cross-default provisions, outstanding revolving credit facilities, and new long-term debt issuances, see Item 8 - Note 9.

Equity offerings In August 2025, the Company entered into an EDA pursuant to which it may issue, offer, and sell, from time to time, up to an aggregate gross sales price of $400.0 million of shares of its common stock through an ATM offering program, which includes the ability to enter into FSAs. Since the establishment of the ATM offering program, the Company did not issue common stock pursuant to the EDA nor enter into any FSAs related to the EDA.

On December 5, 2025, the Company completed a follow-on public offering of 10,152,284 of shares of the Company's common stock at a public offering price of $19.70 per share. In addition, on December 23, 2025, the underwriters exercised their option to purchase 1,522,842 additional shares of the Company's common stock. Pursuant to the FSAs entered into in connection with the offering, the Company has discretion to settle the FSAs on one or more settlement dates prior to December 6, 2027, subject to certain price adjustments as set forth in the FSAs as well as adjustments for transaction and other associated fees. The FSAs will be physically settled with shares of common stock issued by the Company, unless the Company elects to settle the FSAs in net cash or net shares, subject to certain conditions. If the Company elects to physically settle the FSAs, the Company will physically issue shares of common stock to the banking counterparties at the then-applicable forward sale price and receive proceeds at that time.

Actual cash proceeds, if any, for settlement of FSAs will depend on the method and timing the Company elects for settlement. Prior to settlement, the potentially issuable shares pursuant to the FSAs will be reflected in the Company's diluted earnings per share calculation using the treasury stock method. For more detailed information about the Company's equity transactions, see Item 8 - Note 11.

Dividend restrictions

For information on the Company's dividends and dividend restrictions, see Item 8 - Note 11.

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Material cash requirements

For more information on the Company's contractual obligations on long-term debt, operating leases and purchase commitments, see Item 8 - Notes 9 and 17. At December 31, 2025, the Company's material cash requirements under these obligations were as follows:

*    Unamortized debt issuance costs and discount are excluded from the table.

**    Represents the estimated interest payments associated with the Company's long-term debt outstanding at December 31, 2025, assuming current interest rates and consistent amounts outstanding until their respective maturity dates over the periods indicated in the table above.

Material short-term cash requirements of the Company include repayment of outstanding borrowings and interest payments on those agreements, payments on operating lease agreements, payment of obligations on purchase commitments and asset retirement obligations. At December 31, 2025, the current portion of asset retirement obligations was $329,000 and was included in Other accrued liabilities on the Consolidated Balance Sheets.

Material long-term cash requirements of the Company include repayment of outstanding borrowings and interest payments on those agreements, payments on operating lease agreements, payment of obligations on purchase commitments and asset retirement obligations. At December 31, 2025, the Company had total liabilities of $431.9 million related to asset retirement obligations that are excluded from the table above. Due to the nature of these obligations, the Company cannot determine precisely when the payments will be made to settle these obligations. For more information, see Item 8 - Note 10.

Not reflected in the previous table are $1.5 million in uncertain tax positions at December 31, 2025.

The Company's minimum funding requirements for its defined benefit pension plans for 2026, which are not reflected in the previous table, is $3.8 million. For information on potential contributions above the funding minimum requirements, see item 8 - Note 15.

The Company's MEPP contributions are based on union employee payroll, which cannot be determined in advance for future periods. The Company may also be required to make additional contributions to its MEPP as a result of its funded status. For more information, see Item 1A - Risk Factors and Item 8 - Note 15.

New Accounting Standards

For information regarding new accounting standards, see Item 8 - Note 2, which is incorporated herein by reference.

Critical Accounting Estimates

The Company has prepared its financial statements in conformity with GAAP. The preparation of its financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, and disclosure of contingent assets and liabilities, at the date of the financial statements, as well as the reported amounts of revenues and expenses during the reporting period. Management reviews these estimates and assumptions based on historical experience, changes in business conditions and other relevant factors believed to be reasonable under the circumstances.

Critical accounting estimates are defined as estimates that require management to make assumptions about matters that are uncertain at the time the estimate was made and changes in the estimates could have a material impact on the Company's financial position or results of operations. The Company's critical accounting estimates are subject to judgments and uncertainties that affect the application of its significant accounting policies discussed in Item 8 - Note 2. As additional information becomes available, or actual amounts are determinable, the recorded estimates are revised.

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Consequently, the Company's financial position or results of operations may be materially different when reported under different conditions or when using different assumptions in the application of the following critical accounting estimates.

Goodwill

The Company performs its goodwill impairment testing annually in the fourth quarter. In addition, the test is performed on an interim basis whenever events or circumstances indicate that the carrying amount of goodwill may not be recoverable. Examples of such events or circumstances may include a significant adverse change in business climate, weakness in an industry in which the Company's reporting units operate or recent significant cash or operating losses with expectations that those losses will continue.

The Company has determined that the reporting units for its goodwill impairment test are its operating segments, or components of an operating segment, that constitute a business for which discrete financial information is available and for which segment management regularly reviews the operating results. As of December 31, 2025, the only operating segment with goodwill was the natural gas distribution segment. For more information on the Company's operating segments, see Item 8 - Note 14.

Goodwill impairment, if any, is measured by comparing the fair value of each reporting unit to its carrying value. If the fair value of a reporting unit exceeds its carrying value, the goodwill of the reporting unit is not impaired. If the carrying value of a reporting unit exceeds its fair value, the Company must record an impairment loss for the amount that the carrying value of the reporting unit, including goodwill, exceeds the fair value of the reporting unit. For the years ended December 31, 2025, 2024, and 2023, there were no impairment losses recorded.

At October 31, 2025, the Company's annual impairment testing indicated there was no impairment at its natural gas distribution reporting unit. The estimated fair value of the natural gas distribution reporting unit substantially exceeded its carrying value ("cushion"), which includes $345.7 million of goodwill, by approximately 41 percent. The increase in the natural gas distribution reporting unit's cushion from the prior year was primarily driven by improved valuation results under the market approach, reflecting higher industry multiples, as well as an increase in the income approach valuation due to additional rate relief in 2025 compared to 2024.

Determining the fair value of a reporting unit requires judgment and the use of significant estimates which include assumptions about the Company's future revenue, profitability and cash flows, long-term growth rates, amount and timing of estimated capital expenditures, inflation rates, risk adjusted cost of capital, operational plans, and current and future economic conditions, among others. The fair value of each reporting unit is determined using a weighted combination of income and market approaches. The Company believes that the estimates and assumptions used in its impairment assessments are reasonable and based on available market information.

The Company uses a discounted cash flow methodology for its income approach. Under the income approach, the discounted cash flow model determines fair value based on the present value of projected cash flows over a specified period and a residual value related to future cash flows beyond the projection period. Both values are discounted using a rate which reflects the best estimate of the risk adjusted cost of capital at each reporting unit. The risk adjusted cost of capital was 5.8 percent, 5.9 percent and 6.7 percent for 2025, 2024, and 2023, respectively.

Under the market approach, the Company estimates fair value using various multiples derived from enterprise value to EBITDA for comparative peer companies. These multiples are applied to operating data to arrive at an indication of fair value. In addition, the Company also uses a rate base multiple, based on recent comparable industry transactions. With the exception of the rate base trading multiple, the Company adds a reasonable control premium when calculating the fair value utilizing the peer multiples, which is estimated as the premium that would be received in a sale in an orderly transaction between market participants. The Company used a 20 percent control premium in 2025, 2024, and 2023.

The Company uses significant judgment in estimating its five-year forecast. The assumptions underlying cash flow projections are in sync as applicable with the Company's strategy and assumptions. Future projections are heavily correlated with the current year results of operations. Future results of operations may vary due to economic and financial impacts. The long-term growth rates are developed by management based on industry data, management's knowledge of the industry and management's strategic plans, which was 3.0 percent in 2025, 2024, and 2023.

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Regulatory accounting

The Company is subject to rate regulation by state public service commissions and/or the FERC. Regulatory assets generally represent incurred or accrued costs that have been deferred and are expected to be recovered in rates charged to customers. Regulatory liabilities generally represent amounts that are expected to be refunded to customers in future rates or amounts collected in current rates for future costs.

Management continually assesses the likelihood of recovery in future rates of incurred costs and refunds to customers associated with regulatory assets and liabilities. Decisions made by the various regulatory agencies can directly impact the amount and timing of these items. Therefore, expected recovery or refund of these deferred items generally is based on specific ratemaking decisions or precedent for each item. If future recovery of costs is no longer probable, the Company would be required to include those costs in the statement of income or accumulated other comprehensive loss in the period in which it is no longer deemed probable. The Company believes that the accounting subject to rate regulation remains appropriate and its regulatory assets are probable of recovery in current rates or in future rate proceedings. At December 31, 2025 and 2024, the Company's regulatory assets were $476.8 million and $537.8 million, respectively, and regulatory liabilities were $620.9 million and $596.3 million, respectively. At December 31, 2025 and 2024, regulatory assets in recovery were $437.6 million and $478.5 million, respectively, and regulatory assets not in recovery were $39.2 million and $59.3 million, respectively.

Pension and other postretirement benefits

The Company has noncontributory defined benefit pension plans and other postretirement benefit plans for certain eligible employees. Various actuarial assumptions are used in calculating the benefit expense (income) and liability (asset) related to these plans. Costs of providing pension and other postretirement benefits bear the risk of change, as they are dependent upon numerous factors based on assumptions of future conditions.

The Company makes various assumptions when determining plan costs, including the current discount rates and the expected long-term return on plan assets, actuarially determined mortality data and health care cost trend rates. In selecting the expected long-term return on plan assets, which is considered to be one of the key variables in determining benefit expense or income, the Company considers historical returns, current market conditions, the mix of investments and expected future market trends, including changes in interest rates and equity and bond market performance. Another key variable in determining benefit expense or income is the discount rate. In selecting the discount rate, the Company matches forecasted future cash flows of the pension and postretirement plans to a yield curve which consists of a hypothetical portfolio of high-quality corporate bonds with varying maturity dates, as well as other factors, as a basis. The Company's pension and other postretirement benefit plan assets are primarily made up of equity and fixed-income investments. Fluctuations in actual equity and bond market returns, as well as changes in general interest rates, may result in increased or decreased pension and other postretirement benefit costs in the future. Health care cost trend rates are determined by historical and future trends.

The Company believes the estimates made for its pension and other postretirement benefits are reasonable based on the information that is known when the estimates are made. These estimates and assumptions are subject to a number of variables and are expected to change in the future. Estimates and assumptions will be affected by changes in the discount rate, the expected long-term return on plan assets and health care cost trend rates. A 50 basis point change in the assumed discount rate and the expected long-term return on plan assets would have had the following effects at December 31, 2025:

60 MDU Resources Group, Inc. Form 10-K

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A 100 basis point change in the assumed health care cost trend rates would have had the following effects at December 31, 2025:

The Company plans to continue to use its current methodologies to determine plan costs. For more information on the assumptions used in determining plan costs, see Item 8 - Note 15.

Income taxes

The Company is required to make judgments regarding the potential tax effects of various financial transactions and ongoing operations to estimate the Company's obligation to taxing authorities. These tax obligations include income, property, franchise and sales/use taxes. Judgments related to income taxes require the recognition in the Company's financial statements that a tax position is more-likely-than-not to be sustained on audit.

Judgment and estimation is required in developing the provision for income taxes and the reporting of tax-related assets and liabilities and, if necessary, any valuation allowances. The interpretation of tax laws can involve uncertainty, since tax authorities may interpret such laws differently. Actual income tax could vary from estimated amounts and may result in favorable or unfavorable impacts to net income, cash flows and tax-related assets and liabilities. In addition, the effective tax rate may be affected by other changes including the allocation of property, payroll and revenues between states.

The Company assesses the deferred tax assets for recoverability taking into consideration historical and anticipated earnings levels; the reversal of other existing temporary differences; available net operating losses and tax carryforwards; and available tax planning strategies that could be implemented to realize the deferred tax assets. Based on this assessment, management must evaluate the need for, and amount of, a valuation allowance against the deferred tax assets. As facts and circumstances change, adjustment to the valuation allowance may be required.

MDU Resources Group, Inc. Form 10-K 61

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