Form 8-K

8-K — ONE Gas, Inc.

Accession: 0001587732-26-000019

Filed: 2026-05-04

Period: 2026-05-04

CIK: 0001587732

SIC: 4924 (NATURAL GAS DISTRIBUTION)

Item: Results of Operations and Financial Condition

Item: Regulation FD Disclosure

Item: Other Events

Item: Financial Statements and Exhibits

Documents

8-K — ogs-20260504.htm (Primary)

EX-99.1 (ogs3312026earningsrelease.htm)

GRAPHIC (logoletterheadb27.jpg)

XML — IDEA: XBRL DOCUMENT (R1.htm)

8-K

8-K (Primary)

Filename: ogs-20260504.htm · Sequence: 1

ogs-20260504

0001587732false00015877322026-05-042026-05-04

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15(d) OF THE

SECURITIES EXCHANGE ACT OF 1934

(Date of report) May 4, 2026

(Date of earliest event reported) May 4, 2026

ONE Gas, Inc.

(Exact name of registrant as specified in its charter)

Oklahoma 001-36108 46-3561936

(State or other jurisdiction (Commission (IRS Employer

of incorporation) File Number) Identification No.)

15 East Fifth Street; Tulsa, OK

(Address of principal executive offices)

74103

(Zip code)

(918) 947-7000

(Registrant’s telephone number, including area code)

Not Applicable

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐ Written communication pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class Trading Symbol Name of each exchange on which registered

Common Stock, par value $0.01 per share OGS New York Stock Exchange

NYSE Texas

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2).

☐ Emerging growth company

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

The information disclosed in Items 2.02 and 7.01, including Exhibit 99.1 hereto, is being furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the Exchange Act), or otherwise subject to the liabilities under that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act except as expressly set forth by specific reference in such filing.

Item 2.02 Results of Operations and Financial Condition

On May 4, 2026, we announced our results of operations for the quarter ended March 31, 2026. The news release is furnished as Exhibit 99.1 and incorporated by reference herein.

Item 7.01 Regulation FD Disclosure

On May 4, 2026, we announced our results of operations for the quarter ended March 31, 2026, affirmed our 2026 financial guidance and announced that our board of directors declared a cash dividend of 68 cents per share of common stock. The news release is furnished as Exhibit 99.1 and is incorporated by reference herein.

Item 8.01 Other Events

On May 4, 2026, our board of directors declared a cash dividend of 68 cents per share of common stock, payable June 2, 2026, to shareholders of record at the close of business on May 18, 2026.

Item 9.01 Financial Statements and Exhibits

(d) Exhibits

Exhibit

Number Description

99.1

News release issued by ONE Gas, Inc. dated May 4, 2026.

104 Cover Page Interactive Data File (embedded within the Inline XBRL document).

SIGNATURE

Pursuant to the requirements of the Exchange Act, the registrant has duly caused this report to be signed on its behalf by the undersigned, hereunto duly authorized.

ONE Gas, Inc.

Date: May 4, 2026 By: /s/ Christopher P. Sighinolfi

Christopher P. Sighinolfi

Senior Vice President and

Chief Financial Officer

EX-99.1

Filename: ogs3312026earningsrelease.htm · Sequence: 2

Document

Exhibit 99.1

May 4, 2026 Analyst Contact: Erin Dailey

918-947-7441

Media Contact: Leah Harper

918-947-7123

ONE Gas Announces First Quarter 2026 Financial Results; Affirms 2026 Financial Guidance

Declares Second Quarter Dividend

Analyst call and webcast scheduled tomorrow, May 5 at 11 a.m. EDT

TULSA, Okla. - May 4, 2026 - ONE Gas, Inc. (NYSE: OGS) today announced its first quarter 2026 financial results, affirmed its 2026 financial guidance and declared its quarterly dividend.

“Our positive performance through a historically warm winter underscores the resilience of our business model and our ability to drive long‑term value while sustaining customer affordability,” said Robert S. McAnnally, chief executive officer. “We are confident in our strategic plan and remain on track to achieve our 2026 financial guidance.”

FINANCIAL RESULTS & HIGHLIGHTS

•First quarter 2026 net income was $128.7 million, or $2.04 per diluted share, compared with $119.4 million, or $1.98 per diluted share, in the same period last year;

•First quarter 2026 adjusted net income was $133.4 million, or $2.11 per diluted share, compared with $120.1 million, or $1.99 per diluted share, in the same period last year;

•While weather across the Company's service areas was 20.5 percent warmer than normal and 24.6 percent warmer than the prior year, the impact on operating income was tempered by weather normalization mechanisms;

•In February 2026, the Company entered into an at-the-market equity distribution agreement under which it may issue and sell shares of common stock with an aggregate offering price up to $225 million;

•For the ninth consecutive year, ONE Gas was awarded the American Gas Association Safety Achievement Award for excellence in employee safety; and

•The board of directors declared a quarterly dividend of $0.68 per share ($2.72 annualized), payable on June 2, 2026, to shareholders of record at the close of business on May 18, 2026.

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ONE Gas Announces First Quarter Financial Results

May 4, 2026

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FIRST QUARTER 2026 FINANCIAL PERFORMANCE

ONE Gas reported operating income of $189.6 million in the first quarter, compared with $180.5 million in the first quarter 2025, which primarily reflects an increase of $27.3 million from new rates.

This increase was partially offset by:

•an increase of $6.8 million in employee-related costs due, in part, to planned investments in the Company’s workforce;

•an increase of $1.3 million in outside services; and

•a decrease of $8.9 million in revenue due to lower sales and transport volumes, net of the impact of weather normalization mechanisms.

Excluding interest related to KGSS-I securitized bonds, net interest expense decreased $3.0 million for the three months ending March 31, 2026. The decrease in interest expense is primarily due to commercial paper borrowings at lower rates and the implementation of Texas House Bill 4384.

Income tax expense includes a credit for amortization of the regulatory liability associated with excess deferred income taxes (EDIT) of $9.5 million and $8.1 million for the three months ended March 31, 2026, and 2025, respectively.

Capital expenditures and asset removal costs were $169.6 million for the first quarter 2026 compared with $177.7 million in the same period last year, primarily representing expenditures for system integrity and extension of service to new areas.

REGULATORY ACTIVITIES UPDATE

In April 2026, Kansas House Bill 2435 was signed into law, amending the Gas System Reliability Surcharge (GSRS) statute effective July 1, 2026. The amendment expands the qualifying infrastructure investments eligible for recovery to include all utility plant investments (excluding allocated corporate costs other than cyber-security related investments), increases the maximum monthly residential surcharge to $1.35 from $0.80 and provides added filing flexibility by allowing one GSRS filing per calendar year, rather than once every 365 days.

In March 2026, Texas Gas Service made a Gas Reliability Infrastructure Program filing for all customers requesting a $36.9 million revenue increase to be effective in July 2026.

In February 2026, Oklahoma Natural Gas filed its annual Performance-Based Rate Change application for the test year ended December 2025. The filing includes a requested $28.7 million base rate revenue increase, $2.6 million energy efficiency incentive and $14.4 million of estimated EDIT to be credited to customers in 2027. A hearing is scheduled for June 11, 2026. Rates may be implemented subject to refund on June 26, 2026.

2026 FINANCIAL GUIDANCE

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ONE Gas Announces First Quarter Financial Results

May 4, 2026

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ONE Gas affirmed the financial guidance it issued on Dec. 1, 2025, as supplemented on Feb. 18, 2026. For 2026, net income is expected to be in the range of $294 million to $302 million, or $4.65 to $4.77 per diluted share, while adjusted net income is expected to be in the range of $306 million to $314 million, or $4.83 to $4.95 per diluted share. The Company continues to expect long-term GAAP and adjusted net income growth of 7 to 9 percent and GAAP and adjusted net income per diluted share growth of 5 to 7 percent, consistent with its established five-year financial outlook.

Capital investments, including asset removal costs, are expected to be approximately $800 million in 2026. Capital investments for extensions to new customers are expected to be approximately $230 million.

EARNINGS CONFERENCE CALL AND WEBCAST

The ONE Gas executive management team will host a conference call on Tuesday, May 5, 2026, at 11 a.m. Eastern Daylight Time (10 a.m. Central Daylight Time). The call also will be carried live on the ONE Gas website.

To participate in the telephone conference call, dial 800-715-9871, passcode 3280987, or log on to www.onegas.com/investors and select Events and Presentations.

If you are unable to participate in the conference call or the webcast, a replay will be available on the ONE Gas website, www.onegas.com, for 30 days. A recording will be available by phone for seven days. The playback call may be accessed at 1-800-770-2030, passcode 3280987.

NON-GAAP DISCLOSURE STATEMENT

This news release includes financial results and guidance for ONE Gas with respect to adjusted net income and adjusted net income per share, which are non-GAAP financial measures as defined by the Securities and Exchange Commission. Adjusted net income and adjusted net income per share are calculated as GAAP net income plus the deferral of an equity portion of a carrying cost attributable to shareholders’ investment capitalized for regulatory purposes but not for financial reporting purposes. These carrying costs relate to property, plant and equipment that has been placed in service, but not yet reflected in base rates. Adjusted net income and adjusted net income per share should not be considered in isolation or as a substitute for GAAP net income or GAAP earnings per share.

Management believes these non‑GAAP measures provide useful information because they offer a more complete view of our overall regulatory economics, reflect the period-specific effects of certain regulatory mechanisms designed to mitigate regulatory lag associated with property, plant and equipment placed in service prior to regulatory action, and reflect the impact of regulatory timing differences that arise under the Company’s rate-setting framework. These adjustments, net of applicable tax effects, are expected to recur as a result of the Company’s regulatory framework and are a consistent part of our earnings profile. A reconciliation of the Company’s GAAP net income and GAAP earnings per share to adjusted net income and adjusted net income per share is provided in the Appendix.

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ONE Gas Announces First Quarter Financial Results

May 4, 2026

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ONE Gas, Inc. (NYSE: OGS) is a 100% regulated natural gas utility, and trades on the New York Stock Exchange and the NYSE Texas under the symbol “OGS.” ONE Gas is included in the S&P MidCap 400 Index and is one of the largest natural gas utilities in the United States.

Headquartered in Tulsa, Oklahoma, ONE Gas provides a reliable and affordable energy choice to more than 2.3 million customers in Kansas, Oklahoma and Texas. Its divisions include Kansas Gas Service, the largest natural gas distributor in Kansas; Oklahoma Natural Gas, the largest in Oklahoma; and Texas Gas Service, the third largest in Texas, in terms of customers.

For more information and the latest news about ONE Gas, visit onegas.com and follow its social channels: @ONEGas, Facebook, LinkedIn and YouTube.

Some of the statements contained and incorporated in this news release 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 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 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 news release 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 news release. 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, according to experts, 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 information technology 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, climate change, and the related effects on supply, demand, and costs;

•indebtedness 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, storage, 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;

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ONE Gas Announces First Quarter Financial Results

May 4, 2026

Page 5

•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;

•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 upstream transportation, storage, and 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 local distribution company 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 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 our 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.

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ONE Gas Announces First Quarter Financial Results

May 4, 2026

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APPENDIX

ONE Gas, Inc.

CONSOLIDATED STATEMENTS OF INCOME

Three Months Ended

March 31,

(Unaudited) 2026 2025

(Thousands of dollars, except per share amounts)

Total revenues $ 831,711 $ 935,190

Cost of natural gas 393,576 512,462

Operating expenses

Operations and maintenance 146,947 135,295

Depreciation and amortization 76,785 81,704

General taxes 24,811 25,230

Total operating expenses 248,543 242,229

Operating income 189,592 180,499

Other income (expense), net

(2,097) 518

Interest expense, net (32,358) (35,697)

Income before income taxes 155,137 145,320

Income taxes (26,464) (25,901)

Net income

$ 128,673 $ 119,419

Earnings per share

Basic $ 2.05 $ 1.99

Diluted $ 2.04 $ 1.98

Average shares (thousands)

Basic 62,913 60,077

Diluted 63,204 60,266

Dividends declared per share of stock $ 0.68 $ 0.67

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ONE Gas Announces First Quarter Financial Results

May 4, 2026

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APPENDIX

ONE Gas, Inc.

CONSOLIDATED BALANCE SHEETS

March 31, December 31,

(Unaudited) 2026 2025

Assets

(Thousands of dollars)

Property, plant and equipment

Property, plant and equipment $ 9,852,116 $ 9,734,150

Accumulated depreciation and amortization 2,640,623 2,611,952

Net property, plant and equipment 7,211,493 7,122,198

Current assets

Cash and cash equivalents 11,354 10,620

Restricted cash and cash equivalents 11,639 23,107

Total cash, cash equivalents and restricted cash and cash equivalents 22,993 33,727

Accounts receivable, net 405,157 461,631

Materials and supplies 92,987 97,595

Income tax receivable 55,552 55,552

Natural gas in storage 123,920 176,451

Regulatory assets 61,487 49,504

Other current assets 34,544 41,424

Total current assets 796,640 915,884

Goodwill and other assets

Regulatory assets 252,048 256,225

Securitized intangible asset, net 226,359 233,786

Goodwill 157,953 157,953

Pension and other postemployment benefits 47,175 47,012

Other assets 133,933 120,026

Total goodwill and other assets 817,468 815,002

Total assets $ 8,825,601 $ 8,853,084

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ONE Gas Announces First Quarter Financial Results

May 4, 2026

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APPENDIX

ONE Gas, Inc.

CONSOLIDATED BALANCE SHEETS

(Continued)

March 31, December 31,

(Unaudited) 2026 2025

Equity and Liabilities

(Thousands of dollars)

Equity and long-term debt

Common stock, $0.01 par value:

authorized 250,000,000 shares; issued and outstanding 62,761,990 shares at March 31, 2026; issued and outstanding 62,692,392 shares at December 31, 2025

$ 628 $ 627

Paid-in capital 2,530,435 2,530,137

Retained earnings 994,838 909,355

Accumulated other comprehensive income (loss) (179) 4

Total equity 3,525,722 3,440,123

Other long-term debt, excluding current maturities, net of issuance costs 2,133,350 2,133,018

Securitized utility tariff bonds, excluding current maturities, net of issuance costs 206,970 223,020

Total long-term debt, excluding current maturities, net of issuance costs 2,340,320 2,356,038

Total equity and long-term debt 5,866,042 5,796,161

Current liabilities

Current maturities of other long-term debt, net of issuance costs 249,798 249,674

Current maturities of securitized utility tariff bonds, net of issuance costs 31,404 30,566

Notes payable 759,700 737,400

Accounts payable 137,587 222,102

Accrued taxes other than income 71,272 75,568

Regulatory liabilities 21,638 57,277

Customer deposits 54,901 52,871

Other current liabilities 75,980 106,400

Total current liabilities 1,402,280 1,531,858

Deferred credits and other liabilities

Deferred income taxes 999,420 963,874

Regulatory liabilities 441,041 451,620

Other deferred credits 116,818 109,571

Total deferred credits and other liabilities 1,557,279 1,525,065

Commitments and contingencies

Total liabilities and equity $ 8,825,601 $ 8,853,084

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ONE Gas Announces First Quarter Financial Results

May 4, 2026

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APPENDIX

ONE Gas, Inc.

CONSOLIDATED STATEMENTS OF CASH FLOWS

Three Months Ended

(Unaudited) 2026 2025

(Thousands of dollars)

Operating activities

Net income $ 128,673 $ 119,419

Adjustments to reconcile net income to net cash provided by operating activities:

Depreciation and amortization 76,785 81,704

Deferred income taxes 23,293 19,146

Share-based compensation expense 3,837 3,656

Provision for doubtful accounts 2,896 2,331

Changes in assets and liabilities:

Accounts receivable 53,578 (40,690)

Materials and supplies 4,608 3,681

Natural gas in storage 52,531 92,498

Asset removal costs (13,081) (11,089)

Accounts payable (78,600) (72,871)

Accrued taxes other than income (4,296) 2,245

Customer deposits 2,030 (1,320)

Regulatory assets and liabilities - current (51,927) 73,872

Regulatory assets and liabilities - noncurrent 5,894 9,425

Other assets and liabilities - current (26,105) (11,650)

Other assets and liabilities - noncurrent (3,803) 7,102

Cash provided by operating activities

176,313 277,459

Investing activities

Capital expenditures (156,533) (166,597)

Other investing expenditures (2,697) (2,427)

Other investing receipts 5,130 1,179

Cash used in investing activities

(154,100) (167,845)

Financing activities

Borrowings (repayments) of notes payable, net

22,300 (102,700)

Repayment of other long-term debt (4) (4)

Repayment of securitized utility tariff bonds (15,356) (14,547)

Dividends paid (42,678) (40,153)

Tax withholdings related to net share settlements of stock compensation (4,050) (2,559)

Construction advances 6,841 —

Cash provided by financing activities (32,947) (159,963)

Change in cash, cash equivalents, restricted cash and restricted cash equivalents (10,734) (50,349)

Cash, cash equivalents, restricted cash and restricted cash equivalents at beginning of period 33,727 78,537

Cash, cash equivalents, restricted cash and restricted cash equivalents at end of period $ 22,993 $ 28,188

Supplemental cash flow information:

Cash paid for interest, net of amounts capitalized

$ 32,628 $ 36,268

Cash paid (received) for state income taxes $ — $ —

Cash paid (received) for federal income taxes

$ — $ —

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ONE Gas Announces First Quarter Financial Results

May 4, 2026

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APPENDIX

The following table reconciles the Company’s GAAP net income and GAAP earnings per share to adjusted net income and adjusted net income per share:

ONE Gas, Inc.

Three Months Ended

March 31,

2026 2025

(Thousands of dollars, except per share amounts)

Net income - GAAP $ 128,673 $ 119,419

Other income - deferred carrying cost (a) 4,725 648

Income taxes (a) — —

Adjusted net income - non-GAAP $ 133,398 $ 120,067

Earnings per share - GAAP

Basic $ 2.05 $ 1.99

Diluted $ 2.04 $ 1.98

Adjusted net income per share - non-GAAP

Basic $ 2.12 $ 2.00

Diluted $ 2.11 $ 1.99

Average shares (thousands)

Basic 62,913 60,077

Diluted 63,204 60,266

(a) The allowance for earnings on shareholders’ investment capitalized for regulatory purposes but not for financial reporting purposes applied to property, plant and equipment placed in service, but not yet reflected in rates as authorized by our regulators or state law. This increases book income but is non-taxable, creating a permanent tax difference.

ONE Gas, Inc.

2026 Financial Guidance: Reconciliation of non-GAAP to GAAP:

Low

Mid

High

(Thousands of dollars, except per share amounts)

Net income - GAAP $ 294,000 $ 298,000 $ 302,000

Other income - deferred carrying cost (a) 11,890 11,919 12,000

Income taxes (a) — — —

Adjusted net income - non-GAAP $ 305,890 $ 309,919 $ 314,000

Earnings per share - GAAP

Basic $ 4.67 $ 4.73 $ 4.79

Diluted $ 4.65 $ 4.71 $ 4.77

Adjusted net income per share - non-GAAP

Basic $ 4.86 $ 4.92 $ 4.98

Diluted $ 4.83 $ 4.89 $ 4.95

Average shares (thousands)

Basic 62,995 62,995 62,995

Diluted 63,350 63,350 63,350

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ONE Gas Announces First Quarter Financial Results

May 4, 2026

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APPENDIX

ONE Gas, Inc.

INFORMATION AT A GLANCE

Three Months Ended

March 31,

(Unaudited)

2026 2025

(Millions of dollars)

Natural gas sales $ 769.9 $ 870.4

Transportation revenues 40.1 43.8

Securitization customer charges 11.0 11.6

Other revenues 10.7 9.4

Total revenues $ 831.7 $ 935.2

Cost of natural gas 393.5 512.5

Operating costs 171.8 160.5

Depreciation and amortization 76.8 81.7

Operating income $ 189.6 $ 180.5

Net income $ 128.7 $ 119.4

Capital expenditures and asset removal costs $ 169.6 $ 177.7

Volumes (Bcf)

Natural gas sales

Residential 44.0 58.9

Commercial and industrial 15.0 19.2

Other 0.9 1.2

Total sales volumes delivered 59.9 79.3

Transportation 59.1 65.3

Total volumes delivered 119.0 144.6

Average number of customers (in thousands)

Residential 2,138 2,125

Commercial and industrial 163 165

Other 3 3

Transportation 11 12

Total customers 2,315 2,305

Heating Degree Days

Actual degree days 4,159 5,513

Normal degree days 5,232 5,231

Percent colder (warmer) than normal weather (21) % 5 %

Statistics by State

Oklahoma

Average number of customers (in thousands)

939 934

Actual degree days

1,411 1,916

Normal degree days

1,798 1,797

Percent colder (warmer) than normal weather

(22) % 7 %

Kansas

Average number of customers (in thousands)

660 659

Actual degree days

2,070 2,610

Normal degree days

2,486 2,486

Percent colder (warmer) than normal weather

(17) % 5 %

Texas

Average number of customers (in thousands)

716 712

Actual degree days

678 987

Normal degree days

948 948

Percent colder (warmer) than normal weather

(28) % 4 %

###

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v3.26.1

DEI 8-K Notes

May 04, 2026

Cover [Abstract]

Document Type

8-K

Document Period End Date

May 04, 2026

Registrant Name

ONE Gas, Inc.

Entity Incorporation, State or Country Code

Entity Tax Identification Number

46-3561936

Entity Address, Address Line One

15 East Fifth Street

Entity Address, City or Town

Tulsa

Entity Address, State or Province

Entity Address, Postal Zip Code

74103

City Area Code

(918)

Local Phone Number

947-7000

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false

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false

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false

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false

Amendment Flag

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Central Index Key

0001587732

Entity File Number

001-36108

Title of 12(b) Security

Common Stock, par value $0.01 per share

Trading Symbol

OGS

Security Exchange Name

NYSE

Entity Emerging Growth Company

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