ONE Gas, Inc. (OGS) FY 2024 MD&A

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

The following discussion and analysis should be read in conjunction with our audited consolidated financial statements and the Notes to Consolidated Financial Statements in this Annual Report.

EXECUTIVE SUMMARY

We are a 100-percent regulated natural gas distribution company. As such, our regulators determine the rates we are allowed to charge for our service based on the revenue requirements needed to achieve our authorized rates of return. We earn revenues from the delivery of natural gas, but do not earn a profit on the natural gas that we deliver, as those costs are passed through to our customers at cost. The primary components of our revenue requirements are the amount of capital invested in our business, which is also known as rate base, our allowed rate of return on our capital investments and our recoverable operating expenses, including depreciation, interest expense and income taxes. The variable component of our rates is dependent on the consumption of natural gas, which is impacted primarily by the weather and, to a lesser extent, economic activity. While we have WNA mechanisms that adjust customers’ bills when actual HDDs differ from normalized HDDs, these mechanisms are in place for only a portion of the year, except in Kansas, and do not offset all fluctuations in usage resulting from weather variability. Accordingly, the weather can have either a positive or negative impact on our financial performance.

Our financial performance is contingent on a number of factors, including: (1) our regulatory construct, including the rates we are allowed to charge for our service, and the authorized rates of return on our investments in rate base; (2) the consumption of natural gas, which impacts the amount of natural gas sales derived from the variable component of our rates; (3) customer growth; (4) our operating performance; and (5) the perceived value of natural gas relative to other energy sources, particularly electricity, which influences our customers’ choice of natural gas to provide a portion of their energy needs.

We are subject to regulatory requirements for pipeline integrity, pipeline and cyber security, and environmental compliance. These requirements impact our operating expenses and the level of capital expenditures required for compliance. Historically, our regulators have allowed recovery of these expenditures. However, because integrity and environmental regulations are frequently changing, our capital and operating expenditures to comply are changing as well. Although we believe our regulators will continue to allow recovery of such expenditures in the future, we will continue to make these expenditures with no assurance about if, or over what period, we will be permitted to recover them.

RECENT DEVELOPMENTS

Credit Facility - In October 2024, we entered into an agreement that increased the capacity of the ONE Gas Credit Agreement to $1.35 billion from $1.275 billion with commitments from existing lenders and the addition of a new lender. Other than the increased commitments, the maturity date, March 16, 2028, and all other terms and conditions of the ONE Gas Credit Agreement remain unchanged.

Commercial Paper - In October 2024, we increased the capacity of our commercial paper program to $1.35 billion from $1.275 billion.

Equity issuances - On December 27, 2024, we settled under forward contracts 3,160,465 shares (926,465 shares from forwards related to an at-the-market equity distribution agreement and 2,234,000 from forwards related to underwriting agreements) of our common stock for net proceeds of $245.7 million ($75.2 million from forwards related to an at-the market equity distribution agreement and $170.5 million from forwards related to underwriting agreements).

In December 2024, we amended the two forward sale agreements we entered into in September 2023 to extend the maturity date of 223,000 and 180,000 shares of our common stock, to December 31, 2025 from December 31, 2024. The amended forward sale agreements provide for settlement on a date, or dates, to be specified at our discretion but which will occur no later than December 31, 2025.

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In February 2023, we entered into an at-the-market equity distribution agreement under which we may issue and sell shares of our common stock with an aggregate offering price up to $300 million. This at-the-market equity program replaced our previous at-the-market equity program, which began in February 2020, and expired in February 2023. Sales of common stock are made by means of ordinary brokers’ transactions on the NYSE, in block transactions or as otherwise agreed to between us and the sales agent. We are under no obligation to offer and sell common stock under the program. At December 31, 2024, we had $225.5 million of equity available for issuance under the program.

The following table summarizes all of our outstanding forward sale agreements at December 31, 2024:

See “Liquidity and Capital Resources” and Note 7 of the Notes to Consolidated Financial Statements in this Annual Report for additional discussion of our at-the-market equity program.

Dividend - In January 2025, we declared a dividend of $0.67 per share ($2.68 per share on an annualized basis) for shareholders of record as of February 21, 2025, payable on March 7, 2025.

REGULATORY ACTIVITIES

Oklahoma - As required by our tariff, PBRC filings are made annually on or before March 15 until the next general rate case, which is required to be filed on or before June 30, 2027. On February 29, 2024, Oklahoma Natural Gas filed its required PBRC application for the year ended December 2023. The filed request included a $31.8 million base rate revenue increase, $2.4 million energy efficiency incentive, and $12.8 million of estimated EDIT to be credited to customers in 2025. On May 31, 2024, a settlement in the case was filed with a proposed revenue increase of $31.4 million. On June 4, 2024, a hearing was held at the conclusion of which the administrative law judge took the case under advisement. On July 15, 2024, the administrative law judge issued a report to the OCC recommending approval of the settlement agreement. Pursuant to its tariff, Oklahoma Natural Gas placed new rates into effect on June 28, 2024. The OCC issued an order approving the settlement on August 27, 2024.

In March 2023, Oklahoma Natural Gas filed its required PBRC application for the year ended December 2022. The filed request included a $27.6 million base rate revenue increase, $2.5 million energy efficiency incentive, and $11.9 million of estimated EDIT to be credited to customers in 2024. On June 13, 2023, a settlement in the case was filed with a proposed revenue increase of $26.3 million, a $2.5 million energy efficiency incentive, and a $12.6 million EDIT credit. Pursuant to its tariff, Oklahoma Natural Gas placed new rates into effect on June 29, 2023. In July 2023, the OCC issued an order approving the settlement.

Kansas - On March 1, 2024, Kansas Gas Service submitted an application to the KCC requesting an increase to its base rates reflecting investments in its natural gas distribution system. On August 2, 2024, a unanimous settlement agreement was signed by all parties to the rate case and filed with the KCC. A hearing on the unanimous settlement agreement was held on August 13, 2024. On October 3, 2024, the KCC issued an order approving the settlement agreement and new rates became effective on November 1, 2024. Kansas Gas Service’s net base rates will increase by $35 million. Kansas Gas Service was already recovering $35 million from customers through the GSRS; therefore, this settlement represents a total base rate increase of $70 million. The unanimous settlement agreement stipulates a GSRS pre-tax carrying charge of 8.97 percent for subsequent GSRS filings.

In August 2023, Kansas Gas Service submitted an application to the KCC requesting an increase of approximately $8.0 million related to its GSRS. The KCC issued an order in November 2023 authorizing the increase, and the new surcharge became effective on December 1, 2023.

Texas

West-North Service Area - In February 2025, Texas Gas Service made a GRIP filing for all customers in the West-North service area, requesting a $8.2 million increase to be effective in June 2025.

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In March 2024, Texas Gas Service made a GRIP filing for all customers in the West-North service area, requesting an $8.6 million increase to be effective in July 2024. In June of 2024, El Paso and Socorro denied the requested increase. Texas Gas Service filed an appeal of these denials to the RRC on July 8, 2024, which was upheld by the RRC. All other municipalities, and the RRC, approved an increase of $8.5 million or allowed it to take effect with no action. Texas Gas Service implemented new rates in July 2024.

Central-Gulf Service Area - In February 2025, Texas Gas Service made a GRIP filing for all customers in the Central-Gulf service area, requesting a $15.4 million increase to be effective in June 2025.

In June 2024, Texas Gas Service filed a rate case for all customers in the Central-Gulf service area, requesting a $25.8 million increase. Texas Gas Service has invested approximately $355 million in its Central-Gulf service area natural gas distribution system since its last Central-Gulf service area rate case was finalized in August 2020. A portion of this investment, approximately $342 million, is currently recovered through GRIP. On September 27, 2024, the parties filed an uncontested settlement agreement for an increase of $19.3 million based on a 9.7 percent return on equity and 59.6 percent common equity ratio. In November 2024, the RRC approved this settlement and new rates took effect in December 2024.

In February 2024, Texas Gas Service made a GRIP filing for all customers in the Central-Gulf service area, requesting a $12.3 million increase to be effective in June 2024. In May 2024, the RRC and municipalities approved an increase of $12.2 million, and new rates became effective in June 2024.

Rio Grande Valley Service Area - In May 2024, Texas Gas Service made a GRIP filing for all customers in the Rio Grande Valley service area, requesting a $3.7 million increase to be effective in August 2024. In August 2024, the RRC and municipalities approved an increase of $3.6 million, and new rates became effective in September 2024.

In June 2023, Texas Gas Service filed a rate case for all customers in the Rio Grande Valley service area, requesting a $9.8 million increase. In November 2023, the parties filed a signed settlement agreement that included a 9.7 percent ROE and an overall revenue increase of $5.9 million. In January 2024, the administrative law judge issued a proposal for decision recommending approval of the settlement. On January 30, 2024, the RRC approved the administrative law judge’s decision and the new rates went into effect.

See “Regulatory Activities,” “Liquidity and Capital Resources,” and Notes 1 and 3 of the Notes to Consolidated Financial Statements in this Annual Report for additional discussion of the securitization transactions.

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FINANCIAL RESULTS AND OPERATING INFORMATION

We operate in one reportable business segment: regulated public utilities that deliver natural gas to residential, commercial and transportation customers. We evaluate our financial performance principally on net income.

Selected Financial Results - Net income was $222.9 million, or $3.91 per diluted share, $231.2 million, or $4.14 per diluted share, and $221.7 million, or $4.08 per diluted share, for the years ended December 31, 2024, 2023 and 2022, respectively.

The following table sets forth certain selected financial results for our operations for the periods indicated:

Natural gas sales to customers represent revenue from contracts with customers through implied contracts established by our tariffs and rates approved by regulatory authorities, as well as revenues from regulatory mechanisms related to natural gas sales. Additionally, natural gas sales include recovery of the cost of natural gas.

Our natural gas sales include fixed and variable charges related to the delivery of natural gas and gas costs that are passed through to our customers in accordance with our cost of natural gas regulatory mechanisms. Fixed charges reflect the portion of our natural gas sales attributable to the monthly fixed customer charge component of our rates, which does not fluctuate based on customer usage in each period. Variable charges reflect the portion of our natural gas sales that fluctuate with the volumes delivered and billed and the effects of weather normalization.

Transportation revenues represent revenue from contracts with customers through implied contracts established by our tariffs and rates approved by regulatory authorities, as well as tariff-based negotiated contracts.

Securitization customer charges represent revenue from contracts with customers through implied contracts established by the financing order approved by the KCC, related to the securitization of extraordinary costs incurred during Winter Storm Uri in the state of Kansas. See Note 17 of the Notes to Consolidated Financial Statements in this Annual Report for additional discussion of the securitization transaction in Kansas.

Other revenues include primarily miscellaneous service charges, which represent implied contracts with customers established by our tariffs and rates approved by regulatory authorities and other revenues from regulatory mechanisms.

Our average cost of gas rate decreased to $5.32 per Mcf for the year ended December 31, 2024, compared to $7.08 per Mcf in the prior year. Cost of natural gas includes commodity purchases, fuel, storage, transportation, hedging costs and settlement proceeds for natural gas price volatility mitigation programs approved by our regulators and other gas purchase costs recovered through our cost of natural gas regulatory mechanisms and does not include an allocation of general operating costs or depreciation and amortization. These regulatory mechanisms provide a method of recovering natural gas costs on an ongoing basis without a profit. Therefore, although our revenues will fluctuate with the cost of natural gas that we pass-through to our customers, operating income is not affected by fluctuations in the cost of natural gas.

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2024 vs. 2023 - Operating income increased $21.4 million due primarily to the following:

•an increase of $67.9 million from new rates and

•an increase of $6.3 million in residential sales due to net customer growth in Oklahoma and Texas.

These increases were offset partially by:

•an increase of $22.9 million in employee-related costs;

•an increase of $16.9 million in depreciation expense due to additional capital expenditures being placed in service;

•an increase of $6.9 million in ad-valorem taxes;

•an increase of $2.2 million in fleet expense;

•an increase of $1.9 million in outside services; and

•an increase of $1.7 million in insurance expense.

Revenues for the year ended December 31, 2024, include a decrease of $4.3 million associated with KGSS-I, which is offset by a decrease of $2.5 million in amortization and operating expense and $1.7 million in interest expense, net.

Other Factors Affecting Net Income - Other factors that affect net income for the year ended December 31, 2024, compared with 2023, include an decrease of $2.0 million in other income, net and an increase of $31.9 million in interest expense, net. The decrease in other income, net is due primarily to a $1.2 million decrease in the gain on investments associated with our nonqualified deferred compensation plans. The increase in interest expense is due primarily to the issuance of $300 million of 5.10 percent senior notes due 2029 in December 2023, the reopening of the 5.10 percent senior notes in August 2024 in which we issued an additional $250 million, and repayment of $300 million of 3.61 percent senior notes due February 2024 and $473 million of 1.10 percent senior notes due March 2024 upon maturity with commercial paper.

EDIT - The return of EDIT to our customers is not expected to have a material impact on earnings, as any reduction or credit in rates is offset by a reduction in income tax expense. During the years ended December 31, 2024 and 2023, we credited income tax expense $25.7 million and $22.4 million, respectively, for the amortization of the regulatory liability associated with EDIT that was embedded in base rates.

Capital Expenditures and Asset Removal Costs - Our capital expenditures program includes expenditures for pipeline integrity, extending service to new areas, reinforcing and increasing system capabilities, pipeline replacements, automated meter reading, government-mandated pipeline relocations, fleet, facilities, IT assets, and cybersecurity. It is our practice to maintain and upgrade our infrastructure, facilities and systems to ensure safe, reliable, and efficient operations. Asset removal costs include expenditures associated with the replacement or retirement of long-lived assets that result from the construction, development and/or normal use of our assets, primarily our pipeline assets.

Capital expenditures and asset removal costs increased $33.4 million for 2024, compared with 2023, due primarily to expenditures for system integrity and extension of service to new areas. Our capital expenditures and asset removal costs are expected to be approximately $750 million for 2025. While we did not experience a significant impact to our capital expenditure program during the year ended December 31, 2024, our future capital expenditure activity is dependent on a number of factors, including economic conditions and our supply chains for contract labor, materials and supplies.

Selected Operating Information - The following tables set forth certain selected operating information for the periods indicated:

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The increase in the average number of customers for 2024, compared with 2023, is due primarily to the connection of new customers resulting from the extension and expansion of our system in our service areas. For 2024, our average customer count includes 23,000 new customer connections compared to 23,400 in 2023.

The following table reflects total volumes delivered, excluding the effects of WNA mechanisms on sales volumes:

The impact of weather on residential and commercial natural gas sales is mitigated by WNA mechanisms in all jurisdictions.

The following table sets forth the HDDs by state for the periods indicated:

Normal HDDs are established through rate proceedings in each of our jurisdictions for use primarily in weather normalization billing calculations. Normal HDDs disclosed above are based on:

•Oklahoma - A 10-year weighted average as of June 30, 2021, as calculated using 11 weather stations across Oklahoma and weighted on average customer count.

•Kansas - A 30-year rolling average for years 1994-2023 calculated using three weather stations across Kansas and weighted on HDDs by weather station and customers.

•Texas - An average of HDDs authorized in our most recent rate proceeding in each jurisdiction and weighted using a rolling 10-year average of actual natural gas distribution sales volumes by service area.

Actual HDDs are based on the quarter-to-date weighted average of:

•11 weather stations and customers by month for Oklahoma;

•3 weather stations and customers by month for Kansas; and

•9 weather stations and natural gas distribution sales volumes by service area for Texas.

CONTINGENCIES

We are a party to various litigation matters and claims that have arisen in the normal course of our operations. While the results of litigation and claims cannot be predicted with certainty, we believe the reasonably possible losses from such matters, individually and in the aggregate, are not material. Additionally, we believe the probable outcome of such matters will not have a material adverse effect on our results of operations, financial position or cash flows. See Note 15 of the Notes to Consolidated Financial Statements in this Annual Report for information with respect to legal proceedings.

LIQUIDITY AND CAPITAL RESOURCES

General - We have relied primarily on operating cash flow and commercial paper for our liquidity and capital resource requirements. We fund operating expenses, working capital requirements, including purchases of natural gas, and capital expenditures primarily with cash from operations and commercial paper.

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Our stable cash flow and earnings profile is due to the significant residential component of our customer base, the fixed-charge component of our natural gas sales revenues and the rate mechanisms that we have in place. Additionally, we have rate mechanisms in place in our jurisdictions that reduce the lag in earning a return on our capital expenditures and provide for recovery of certain changes in our cost of service by allowing for adjustments to rates between rate cases. We anticipate that our cash flow generated from operations and our expected short- and long-term financing arrangements will enable us to maintain our current and planned level of operations and provide us flexibility to finance our infrastructure investments. Our ability to access capital markets for debt and equity financing under reasonable terms depends on market conditions, our financial condition and credit ratings.

Short-term Debt - The ONE Gas Credit Agreement contains certain financial, operational and legal covenants. Among other things, these covenants include maintaining ONE Gas’ total debt-to-capital ratio of no more than 70 percent at the end of any calendar quarter. At December 31, 2024, our total debt-to-capital ratio was 51.8 percent and we were in compliance with all covenants under the ONE Gas Credit Agreement. Excluding the debt of KGSS-I, which is non-recourse to us, our total debt-to-capital ratio was 49.5 percent. We may reduce the unutilized portion of the ONE Gas Credit Agreement in whole or in part without premium or penalty. The ONE Gas Credit Agreement contains customary events of default. Upon the occurrence of certain events of default, the obligations under the ONE Gas Credit Agreement may be accelerated and the commitments may be terminated.

At December 31, 2024, we had $1.35 million in letters of credit issued and no borrowings under the ONE Gas Credit Agreement, with approximately $1.349 billion of remaining credit, which is available to repay our commercial paper borrowings.

In June 2024, we entered into an agreement that increased the capacity of the ONE Gas Credit Agreement to $1.275 billion from $1.2 billion with commitments from existing lenders and the addition of a new lender.

In October 2024, we entered into an agreement that increased the capacity of the ONE Gas Credit Agreement to $1.35 billion from $1.275 billion with commitments from existing lenders and the addition of a new lender. The ONE Gas Credit Agreement provides for a $1.35 billion revolving unsecured credit facility and includes a $20 million letter of credit subfacility and a $60 million swingline subfacility. We can request an increase in commitments of up to an additional $150 million upon satisfaction of customary conditions, including receipt of commitments from either new lenders or increased commitments from existing lenders. The ONE Gas Credit Agreement is available to provide liquidity for working capital, capital expenditures, acquisitions and mergers, the issuance of letters of credit, and for other general corporate purposes.

In July 2024, we increased the capacity of our commercial paper program to $1.275 billion from $1.2 billion.

In October 2024, we increased the capacity of our commercial paper program to $1.35 billion from $1.275 billion. Under our commercial paper program, we may issue unsecured commercial paper to fund short-term borrowing needs. The maturities of the commercial paper vary but may not exceed 270 days from the date of issue. Commercial paper is generally sold at par less a discount representing an interest factor. At December 31, 2024 and December 31, 2023, we had $914.6 million and $88.5 million of commercial paper outstanding with a weighted-average interest rate of 4.77 percent and 5.60 percent, respectively.

Senior Notes - At December 31, 2024, our long-term debt-to-capital ratio was 43.8 percent. Excluding the debt of KGSS-I, which is non-recourse to us, our long-term debt-to-capital ratio was 40.7 percent. See Note 17 of the Notes to Consolidated Financial Statements in this Annual Report for information with respect to KGSS-I.

At December 31, 2024, we had outstanding $2.2 billion of Senior Notes with none due within the next year. The indenture governing our Senior Notes includes an event of default upon the acceleration of other indebtedness of $100 million or more. Such events of default would entitle the trustee or the holders of 25 percent in aggregate principal amount of the outstanding Senior Notes to declare those Senior Notes immediately due and payable in full.

In August, 2024, we reopened our outstanding 5.10 percent senior notes due 2029 and issued an additional $250 million. After the completion of this offering, the aggregate principal amount of the outstanding 5.10 percent senior notes due 2029 is $550 million. The additional $250 million senior notes were issued at a premium of $4 million, creating an effective interest rate of 4.87 percent.

We repaid our $300 million of 3.61 percent senior notes due February 2024 and our $473 million of 1.10 percent senior notes due March 2024 upon maturity with commercial paper.

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Depending on the series, we may redeem our Senior Notes at par, plus accrued and unpaid interest to the redemption date, starting one month, three months or six months before their maturity dates. Prior to these dates, we may redeem these Senior Notes, in whole or in part, at a redemption price equal to the principal amount, plus accrued and unpaid interest and a make-whole premium. The redemption price will never be less than 100 percent of the principal amount of the respective Senior Note plus accrued and unpaid interest to the redemption date. Our Senior Notes are senior unsecured obligations, ranking equally in right of payment with all of our existing and future unsecured senior indebtedness.

Credit Ratings - Our credit ratings at December 31, 2024, were:

We intend to maintain credit metrics at a level that supports our balanced approach to capital investment and a return of capital to shareholders via a dividend that we believe will be competitive with our peer group.

Securitized Utility Tariff Bonds - At December 31, 2024, we had outstanding $287.3 million of 5.486 percent KGSS-I Securitized Utility Tariff Bonds with $29.0 million due within the next year. The bonds are governed by an indenture between KGSS-I and the indenture trustee. The indenture contains certain covenants that restrict KGSS-I’s ability to sell, transfer, convey, exchange, or otherwise dispose of its assets.

Equity Issuances - On December 27, 2024, we settled under forward contracts 3,160,465 shares (926,465 shares from forwards related to an at-the-market equity distribution agreement and 2,234,000 from forwards related to underwriting agreements) of our common stock for net proceeds of $245.7 million ($75.2 million from forwards related to an at-the market equity distribution agreement and $170.5 million from forwards related to underwriting agreements).

In December 2024, we amended the two forward sale agreements we entered into in September 2023 to extend the maturity date of 223,000 and 180,000 shares of our common stock to December 31, 2025 from December 31, 2024. The amended forward sale agreements provide for settlement on a date, or dates, to be specified at our discretion but which will occur no later than December 31, 2025.

In February 2023, we entered into an at-the-market equity distribution agreement under which we may issue and sell shares of our common stock with an aggregate offering price up to $300 million. This at-the-market equity program replaced our previous at-the-market equity program, which began in February 2020, and expired in February 2023. Sales of common stock are made by means of ordinary brokers’ transactions on the NYSE, in block transactions or as otherwise agreed to between us and the sales agent. We are under no obligation to offer and sell common stock under the program. At December 31, 2024, we had $225.5 million of equity available for issuance under the program.

Pension and Other Postemployment Benefit Plans - For the year ended December 31, 2024, we contributed $1.6 million to our defined benefit pension plans and no contributions were made to our other postemployment benefit plans. For the year ended December 31, 2023, we contributed $1.3 million to our defined benefit pension plans and $2.5 million to our other postemployment benefit plans. Additional information about our pension and other postemployment benefit plans, including anticipated contributions, is included under “Critical Accounting Estimates - Pension and Other Postemployment Benefits” and under Note 11 of the Notes to Consolidated Financial Statements in this Annual Report.

CASH FLOW ANALYSIS

We use the indirect method to prepare our consolidated statements of cash flows. Under this method, we reconcile net income to cash flows provided by operating activities by adjusting net income for those items that impact net income but may not result in actual cash receipts or payments and changes in our assets and liabilities not classified as investing or financing activities during the period. Items that impact net income but may not result in actual cash receipts or payments include, but are not limited to, depreciation and amortization, deferred income taxes, share-based compensation expense and provision for doubtful accounts.

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The following table sets forth the changes in cash flows by operating, investing and financing activities for the periods indicated:

Operating Cash Flows - Changes in cash flows from operating activities are due primarily to changes in sales revenues, natural gas costs and operating expenses discussed in “Financial Results and Operating Information,” the effects of Winter Storm Uri discussed in “Regulatory Activities” and changes in working capital. Changes in natural gas prices and demand for our services or natural gas, whether because of general economic conditions, variations in weather not mitigated by WNA mechanisms, changes in supply or increased competition from other service providers, could affect our earnings and operating cash flows. Typically, our cash flows from operations are greater in the first half of the year compared with the second half of the year.

Operating cash flows were lower for the year ended December 31, 2024, compared to 2023, due primarily to proceeds from government securitization of winter weather costs for Texas Gas Service in March 2023 and working capital changes related to lower cost of gas rates embedded in accounts receivable and natural gas in storage.

Investing Cash Flows - Cash used in investing activities increased for the year ended December 31, 2024, compared to 2023, due primarily to an increase in capital expenditures for system integrity and extension of service to new areas.

Financing Cash Flows - Cash used in financing activities decreased for the year ended December 31, 2024, compared to 2023, due primarily to commercial paper borrowing in excess of repayments of long-term debt and the additional issuance of long-term debt.

ENVIRONMENTAL, SAFETY AND REGULATORY MATTERS

Environmental Matters - We are subject to multiple laws and regulations regarding protection of the environment and natural and cultural resources, which affect many aspects of our present and future operations. Regulated activities include, but are not limited to, those involving air emissions, storm water and wastewater discharges, handling and disposal of solid and hazardous wastes, wetland preservation, plant and wildlife protection, hazardous materials use, storage and transportation, and pipeline and facility construction. These laws and regulations require us to obtain and/or comply with a wide variety of environmental clearances, registrations, licenses, permits and other approvals. Failure to comply with these laws, regulations, licenses and permits or the discovery of presently unknown environmental conditions may expose us to fines, penalties and/or interruptions in our operations that could be material to our results of operations. In addition, emission controls and/or other regulatory or permitting mandates under the CAA and other similar federal and state laws could require unexpected capital expenditures. We cannot assure that existing environmental statutes and regulations will not be revised or that new regulations will not be adopted or become applicable to us. Revised or additional statutes or regulations that result in increased compliance costs or additional operating restrictions could have a material adverse effect on our business, financial condition and results of operations. Our expenditures for environmental investigation and remediation compliance to-date have not been significant in relation to our financial position, results of operations or cash flows, and our expenditures related to environmental matters had no material effects on earnings or cash flows during 2024, 2023 and 2022.

We own or retain legal responsibility for certain environmental conditions at 12 former MGP sites in Kansas. These sites contain contaminants generally associated with MGP sites and are subject to control or remediation under various environmental laws and regulations. A consent agreement with the KDHE governs all environmental investigation and

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remediation work at these sites. The terms of the consent agreement require us to investigate these sites and set remediation activities based upon the results of the investigations and risk analysis. Remediation typically involves the management of contaminated soils and may involve removal of structures and monitoring and/or remediation of groundwater. We have completed or are addressing removal of the source of soil contamination at all 12 sites and continue to monitor groundwater at seven of the 12 sites according to plans approved by the KDHE. Regulatory closure has been achieved at five of the 12 sites, but these sites remain subject to potential future requirements that may result in additional costs.

We have an AAO that allows Kansas Gas Service to defer and seek recovery of costs necessary for investigation and remediation at, and nearby, these 12 former MGP sites that are incurred after January 1, 2017, up to a cap of $15.0 million, net of any related insurance recoveries. Costs approved for recovery in a future rate proceeding would then be amortized over a 15-year period. The unamortized amounts will not be included in rate base or accumulate carrying charges. Following a determination that future investigation and remediation work approved by the KDHE exceeds $15.0 million, net of any related insurance recoveries, Kansas Gas Service is required to file an application with the KCC for approval to increase the $15.0 million cap. During 2024, we received $1.7 million in insurance proceeds for remediation costs related to these sites. At December 31, 2024 and 2023, we have deferred $31.1 million and $32.0 million, respectively, for accrued investigation and remediation costs pursuant to our AAO. On January 3, 2025, Kansas Gas Service requested to increase the cap on the AAO from $15 million to $32 million. The original $15 million cap approved in 2017 was the result of a unanimous settlement agreement and contained additional reporting requirements and obligations. Kansas Gas Service's request to increase the cap leaves all these additional provisions in place.

We also own or retain legal responsibility for certain environmental conditions at a former MGP site in Texas. At the request of the TCEQ, we began investigating the level and extent of contamination associated with the site under their Texas Risk Reduction Program. A preliminary site investigation revealed that this site contains contaminants generally associated with MGP sites and is subject to control or remediation under various environmental laws and regulations. At December 31, 2024, estimated costs associated with expected remediation activities for this site are not material.

Our expenditures for environmental evaluation, mitigation, remediation and compliance to date have not been significant in relation to our financial position, results of operations or cash flows, and our expenditures related to environmental matters had no material effects on earnings or cash flows during the years ended December 31, 2024 and 2023. The reserve for remediation of our MGP sites was $14.3 million at December 31, 2024 and 2023.

Environmental Footprint - We cannot assure that existing environmental statutes and regulations will not be revised or that new regulations will not be adopted or become applicable to us. Revised or additional regulations that result in increased compliance costs or additional operating restrictions could have a material adverse effect on our business, financial condition and results of operations. Our expenditures for environmental investigation, and remediation compliance to-date have not been significant in relation to our financial position, results of operations or cash flows, and our expenditures related to environmental matters had no material effects on earnings or cash flows during 2024, 2023 or 2022.

Pipeline Safety - We are subject to regulation under federal pipeline safety statutes and any analogous state regulations. These include safety requirements for the design, construction, operation, and maintenance of pipelines, including transmission and distribution pipelines. At the federal level, we are regulated by PHMSA. PHMSA regulations require the following for certain pipelines: inspection and maintenance plans; integrity management programs, including the determination of pipeline integrity risks and periodic assessments on certain pipeline segments; an operator qualification program, which includes certain trainings; a public awareness program that provides certain information; and a control room management plan.

As part of regulating pipeline safety, PHMSA promulgates various regulations. As part of the Consolidated Appropriations Act, 2021, the PIPES Act reauthorized PHMSA through 2023 and directed the agency to move forward with several regulatory actions, including the “Pipeline Safety: Class Location Change Requirements” and the “Pipeline Safety: Safety of Gas Transmission and Gathering Pipelines” proposed rulemakings. Congress has also instructed PHMSA to issue final regulations that will require operators of non-rural gas gathering lines and new and existing transmission and distribution pipeline facilities to conduct certain leak detection and repair programs and to require facility inspection and maintenance plans to align with those regulations. To the extent such rulemakings impose more stringent requirements on our facilities, we may be required to incur expenditures that may be material.

Regulatory - Several regulatory initiatives impacted the earnings and future earnings potential of our business. See additional information regarding our regulatory initiatives in the “Regulatory Activities” section of Management’s Discussion and Analysis of Financial Condition and Results of Operations.

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IMPACT OF NEW ACCOUNTING STANDARDS

Information about the impact of new accounting standards, if any, is included in Note 1 of the Notes to Consolidated Financial Statements in this Annual Report.

CRITICAL ACCOUNTING ESTIMATES

The preparation of our consolidated financial statements and related disclosures in accordance with GAAP requires us to make estimates and assumptions with respect to values or conditions that cannot be known with certainty that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the consolidated financial statements. These estimates and assumptions also affect the reported amounts of revenues and expenses during the reporting period. Although we believe these estimates and assumptions are reasonable, actual results could differ from our estimates.

The following summary sets forth what we consider to be our most critical estimates and accounting policies. Our critical accounting policies are defined as those estimates and policies most important to the portrayal of our financial condition and results of operations and that require management’s most difficult, subjective or complex judgment, particularly because of the need to make estimates concerning the impact of inherently uncertain matters.

Regulation - Our operations are subject to regulation with respect to rates, service, maintenance of pipeline and accounting records and various other matters by the respective regulatory authorities in the states in which we operate. We account for the financial effects of the ratemaking and accounting practices and policies of the various regulatory authorities in our consolidated financial statements. We record regulatory assets for costs that have been deferred for which future recovery through customer rates is considered probable and regulatory liabilities when it is probable that revenues will be reduced for amounts that will be returned to customers through the ratemaking process. As a result, certain costs that would normally be expensed under GAAP are capitalized or deferred on the balance sheet because it is probable they can be recovered through rates. Discontinuing the application of this method of accounting for regulatory assets and liabilities could significantly increase our operating expenses, as fewer costs would likely be capitalized or deferred on the balance sheet, which could reduce our net income. Further, regulation may impact the period in which revenues or expenses are recognized. The amounts to be recovered or recognized are based upon historical experience and our understanding of the regulations. The impact of regulation on our operations may be affected by decisions of the regulatory authorities or the issuance of new regulations.

For further discussion of regulatory assets and liabilities, see Note 3 of the Notes to Consolidated Financial Statements in this Annual Report.

Revenue Recognition - For regulated deliveries of natural gas, we read meters and bill customers on a monthly cycle. We recognize revenues upon the delivery of natural gas or services rendered to customers. The billing cycles for customers do not necessarily coincide with the accounting periods used for financial reporting purposes. We accrue unbilled revenues for natural gas that has been delivered but not yet billed at the end of an accounting period. Accrued unbilled revenue is based on a percentage estimate of amounts unbilled each month, which is dependent upon a number of factors, some of which require management’s judgment. These factors include customer consumption patterns and the impact of weather on usage. The accrued unbilled natural gas sales revenue at December 31, 2024 and 2023 was $212.0 million and $191.4 million, respectively, and is included in accounts receivable on our consolidated balance sheets.

We have determined the majority of our natural gas sales and transportation tariffs to be implied contracts with customers, which are settled over time, where our performance obligation is settled with our customer when natural gas is delivered and simultaneously consumed by the customer. In addition, we use the invoice method practical expedient, where we recognize revenue for volumes delivered for which we have a right to invoice. For our other utility revenue, which are primarily one-time service fees that meet the requirements under ASC 606, the performance obligation is satisfied at a point in time when services are rendered to the customer. Certain revenues that do not meet the requirements under ASC 606 as revenues from contracts with customers are reflected as other revenues in determining total revenue. See Note 2 of the Notes to Consolidated Financial Statements in this Annual Report for additional information regarding our revenues.

Pension and Other Postemployment Benefits - We have defined benefit pension plans covering eligible retirees and eligible employees. We also sponsor welfare plans that provide other postemployment medical and life insurance benefits to eligible retirees and employees who retire with at least five years of service.

To calculate the expense and liabilities related to our plans, we utilize an outside actuarial consultant, which uses statistical and other factors to anticipate future events. These factors include assumptions about the discount rate, expected return on plan assets, rate of future compensation increases, age and mortality and employment periods. We use tables issued by the Society of

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Actuaries to estimate mortality rates. In determining the projected benefit costs, assumptions can change from period to period and may result in material changes in the costs and liabilities we recognize.

For the year ended December 31, 2024, we contributed $1.6 million to our defined benefit pension plans and no contributions were made to our other postemployment benefit plans. For the year ended December 31, 2023, we contributed $1.3 million to our defined benefit pension plans and $2.5 million to our other postemployment benefit plans. In 2025, our contributions are expected to be $9.8 million to our defined benefit pension plans, and no contributions are expected to be made to our other postemployment benefit plans.

We recorded net periodic benefit credits for our defined benefit pension plans, prior to regulatory deferrals, of $5.5 million in 2024, and estimate that in 2025, we will record net periodic benefit cost of approximately $5.7 million. Net periodic benefits credits for our postemployment benefit plans, prior to regulatory deferrals, were $0.4 million in 2024, and we estimate that in 2025, we will record a credit of approximately $0.2 million, prior to regulatory deferrals.

The following table sets forth the significant assumptions used to determine our estimated 2025 net periodic benefit cost related to our defined benefit pension and other postemployment benefit plans and sensitivity to changes with respect to these assumptions:

(a) Approximate impact a quarter percentage point decrease in the assumed rate would have on net periodic pension costs.

(b) Approximate impact a quarter percentage point decrease in the assumed rate would have on defined benefit pension obligation.

See Note 11 of the Notes to Consolidated Financial Statements in this Annual Report for additional information regarding our pension and other postretirement benefit plans.

Contingencies - Our accounting for contingencies covers a variety of business activities, including contingencies for legal and environmental exposures. We accrue these contingencies when our assessments indicate that it is probable that a liability has been incurred or an asset will not be recovered and an amount can be reasonably estimated. We expense legal fees as incurred and base our legal liability estimates on currently available facts and our assessments of the ultimate outcome or resolution. Accruals for estimated losses from environmental remediation obligations generally are recognized no later than the completion of a remediation feasibility study. Recoveries of environmental remediation costs from other parties are recorded as assets when their receipt is deemed probable.

Our expenditures for environmental evaluation, mitigation, remediation and compliance to date have not been significant in relation to our financial position, results of operations or cash flows, and our expenditures related to environmental matters had no material effect on earnings or cash flows for the years ended December 31, 2024, 2023 and 2022. Environmental issues may exist with respect to these MGP sites that are unknown to us. Accordingly, future costs are dependent on the final determination and regulatory approval of any remedial actions, the complexity of the site, level of remediation required, changing technology and governmental regulations, and to the extent not recovered by insurance or recoverable in rates from our customers, could be material to our financial condition, results of operations or cash flows.

See “Environmental Matters” and Note 15 of the Notes to Consolidated Financial Statements in this Annual Report for additional discussion of contingencies.

FORWARD-LOOKING STATEMENTS

Some of the statements contained and incorporated in this Annual Report are forward-looking statements within the meaning of Section 27A of the Securities Act and Section 21E of the Exchange Act. The forward-looking statements relate to our anticipated financial performance, liquidity, management’s plans and objectives for our future operations, our business prospects, the outcome of regulatory and legal proceedings, market conditions and other matters. We make these forward-looking statements in reliance on the safe harbor protections provided under the Private Securities Litigation Reform Act of

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1995. The following discussion is intended to identify important factors that could cause future outcomes to differ materially from those set forth in the forward-looking statements.

Forward-looking and other statements in this Annual Report regarding our environmental, social and other sustainability plans and goals are not an indication that these statements are necessarily material to investors or required to be disclosed in our filings with the SEC. In addition, historical, current, and forward-looking environmental, social and sustainability-related statements may be based on standards for measuring progress that are still developing, internal controls and processes that continue to evolve, and assumptions that are subject to change in the future.

Forward-looking statements include the items identified in the preceding paragraph, the information concerning possible or assumed future results of our operations and other statements contained or incorporated in this Annual Report identified by words such as “anticipate,” “estimate,” “expect,” “project,” “intend,” “plan,” “believe,” “should,” “goal,” “forecast,” “guidance,” “could,” “may,” “continue,” “might,” “potential,” “scheduled,” “likely,” and other words and terms of similar meaning.

One should not place undue reliance on forward-looking statements, which are applicable only as of the date of this Annual Report. Known and unknown risks, uncertainties and other factors may cause our actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by forward-looking statements. Those factors may affect our operations, costs, liquidity, markets, products, services and prices. In addition to any assumptions and other factors referred to specifically in connection with the forward-looking statements, factors that could cause our actual results to differ materially from those contemplated in any forward-looking statement include, among others, the following:

•our ability to recover costs, income taxes and amounts equivalent to the cost of property, plant and equipment, regulatory assets and our allowed rate of return in our regulated rates or other recovery mechanisms;

•cyber-attacks, which, continue to increase in volume and sophistication, or breaches of technology systems that could disrupt our operations or result in the loss or exposure of confidential or sensitive customer, employee, vendor, counterparty or Company information; further, increased remote working arrangements have required enhancements and modifications to our IT infrastructure (e.g. Internet, Virtual Private Network, remote collaboration systems, etc.), and any failures of the technologies, including third-party service providers, that facilitate working remotely could limit our ability to conduct ordinary operations or expose us to increased risk or effect of an attack;

•our ability to manage our operations and maintenance costs;

•changes in regulation of natural gas distribution services, particularly those in Oklahoma, Kansas and Texas;

•the economic climate and, particularly, its effect on the natural gas requirements of our residential and commercial customers;

•the length and severity of a pandemic or other health crisis which could significantly disrupt or prevent us from operating our business in the ordinary course for an extended period;

•competition from alternative forms of energy, including, but not limited to, electricity, solar power, wind power, geothermal energy and biofuels;

•adverse weather conditions and variations in weather, including seasonal effects on demand and/or supply, the occurrence of severe storms in the territories in which we operate, and climate change, and the related effects on supply, demand, and costs;

•indebtedness, which could make us more vulnerable to general adverse economic and industry conditions, limit our ability to borrow additional funds and/or place us at competitive disadvantage compared with competitors;

•our ability to secure reliable, competitively priced and flexible natural gas transportation and supply, including decisions by natural gas producers to reduce production or shut-in producing natural gas wells and expiration of existing supply and transportation and storage arrangements that are not replaced with contracts with similar terms and pricing;

•our ability to complete necessary or desirable expansion or infrastructure development projects, which may delay or prevent us from serving our customers or expanding our business;

•operational and mechanical hazards or interruptions;

•adverse labor relations;

•the effectiveness of our strategies to reduce earnings lag, revenue protection strategies and risk mitigation strategies, which may be affected by risks beyond our control such as commodity price volatility, counterparty performance or creditworthiness and interest rate risk;

•the capital-intensive nature of our business, and the availability of and access to, in general, funds to meet our debt obligations prior to or when they become due and to fund our operations and capital expenditures, either through (i) cash on hand, (ii) operating cash flow, or (iii) access to the capital markets and other sources of liquidity;

•our ability to obtain capital on commercially reasonable terms, or on terms acceptable to us, or at all;

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•limitations on our operating flexibility, earnings and cash flows due to restrictions in our financing arrangements;

•cross-default provisions in our borrowing arrangements, which may lead to our inability to satisfy all of our outstanding obligations in the event of a default on our part;

•changes in the financial markets during the periods covered by the forward-looking statements, particularly those affecting the availability of capital and our ability to refinance existing debt and fund investments and acquisitions to execute our business strategy;

•actions of rating agencies, including the ratings of debt, general corporate ratings and changes in the rating agencies’ ratings criteria;

•changes in inflation and interest rates;

•our ability to recover the costs of natural gas purchased for our customers and any related financing required to support our purchase of natural gas supply;

•impact of potential impairment charges;

•volatility and changes in markets for natural gas and our ability to secure additional and sufficient liquidity on reasonable commercial terms to cover costs associated with such volatility;

•possible loss of LDC franchises or other adverse effects caused by the actions of municipalities;

•payment and performance by counterparties and customers as contracted and when due, including our counterparties maintaining ordinary course terms of supply and payments;

•changes in existing or the addition of new environmental, safety, tax, cybersecurity and other laws or regulations to which we and our subsidiaries are subject, including those that may require significant expenditures, significant increases in operating costs or, in the case of noncompliance, substantial fines or penalties;

•the effectiveness of our risk-management policies and procedures, and employees violating our risk-management policies;

•the uncertainty of estimates, including accruals and costs of environmental remediation;

•advances in technology, including technologies that increase efficiency or that improve electricity’s competitive position relative to natural gas;

•population growth rates and changes in the demographic patterns of the markets we serve in Oklahoma, Kansas and Texas, and economic conditions in these areas;

•acts of nature and naturally occurring disasters;

•political unrest and the potential effects of threatened or actual terrorism and war;

•the sufficiency of insurance coverage to cover losses;

•the effects of our strategies to reduce tax payments;

•changes in accounting standards;

•changes in corporate governance standards;

•existence of material weaknesses in our internal controls;

•our ability to comply with all covenants in our indentures and the ONE Gas Credit Agreement, a violation of which, if not cured in a timely manner, could trigger a default of our obligations;

•our ability to attract and retain talented employees, management and directors, and any shortage of skilled-labor;

•unexpected increases in the costs of providing health care benefits, along with pension and postemployment health care benefits, as well as declines in the discount rates on, declines in the market value of the debt and equity securities of, and increases in funding requirements for, our defined benefit plans; and

•our ability to successfully complete merger, acquisition or divestiture plans, regulatory or other limitations imposed as a result of a merger, acquisition or divestiture, and the success of the business following a merger, acquisition or divestiture.

These factors are not necessarily all of the important factors that could cause actual results to differ materially from those expressed in any of our forward-looking statements. Other factors could also have material adverse effects on our future results. These and other risks are described in greater detail in Part 1, Item 1A, Risk Factors, in this Annual Report. All forward-looking statements attributable to us or persons acting on our behalf are expressly qualified in their entirety by these factors. Other than as required under securities laws, we undertake no obligation to update publicly any forward-looking statement whether as a result of new information, subsequent events or change in circumstances, expectations or otherwise.