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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
FORM 10-Q

☒ | QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the quarterly period ended September 30, 2025
OR

☐ | TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from _____________ to ______________
Commission file number 1-03480
MDU RESOURCES GROUP, INC.
(Exact name of registrant as specified in its charter)

Delaware |  | 30-1133956
(State or other jurisdiction of incorporation or organization) |  | (I.R.S. Employer Identification No.)

1200 West Century Avenue
P.O. Box 5650
Bismarck, North Dakota 58506-5650
(Address of principal executive offices)
(Zip Code)
(701) 530-1000
(Registrant's telephone number, including area code)
Securities registered pursuant to Section 12(b) of the Act:

Title of each class | Trading symbol(s) | Name of each exchange on which registered
Common Stock, par value $1.00 per share | MDU | New York Stock Exchange

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ☒ No ☐.
Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes ☒ No ☐.
Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company," and "emerging growth company" in Rule 12b-2 of the Exchange Act.

Large Accelerated Filer | ☒ | Accelerated Filer | ☐
Non-Accelerated Filer | ☐ | Smaller Reporting Company | ☐
|  | 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. ☐
Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No ☒.
Indicate the number of shares outstanding of each of the issuer's classes of common stock, as of November 3, 2025: 204,331,170 shares.
1

Index
| Page
Definitions | 3
Introduction | 5
Part I -- Financial Information |
Item 1. Financial Statements | 6
Consolidated Statements of Income -- Three and Nine Months Ended September 30, 2025 and 2024 | 6
Consolidated Statements of Comprehensive Income -- Three and Nine Months Ended September 30, 2025 and 2024 | 7
Consolidated Balance Sheets -- September 30, 2025 and 2024, and December 31, 2024 | 8
Consolidated Statements of Equity -- Nine Months Ended September 30, 2025 and 2024 | 9
Consolidated Statements of Cash Flows -- Nine Months Ended September 30, 2025 and 2024 | 11
Notes to Consolidated Financial Statements | 12
1. Basis of presentation | 12
2. New accounting standards | 13
3. Discontinued operations | 13
4. Seasonality of operations | 15
5. Receivables and allowance for expected credit losses | 15
6. Inventories and natural gas in storage | 16
7. Earnings per share | 16
8. Equity | 16
9. Revenue from contracts with customers | 17
10. Regulatory assets and liabilities | 19
11. Environmental allowances and obligations | 20
12. Fair value measurements | 20
13. Debt | 23
14. Cash flow information | 24
15. Business segment data | 24
16. Employee benefit plans | 28
17. Regulatory matters | 29
18. Commitments and contingencies | 30
19. Subsequent events | 32
Item 2. Management's Discussion and Analysis of Financial Condition and Results of Operations | 33
Item 3. Quantitative and Qualitative Disclosures About Market Risk | 52
Item 4. Controls and Procedures | 53
Part II -- Other Information |
Item 1. Legal Proceedings | 54
Item 1A. Risk Factors | 54
Item 2. Unregistered Sales of Equity Securities and Use of Proceeds | 54
Item 5. Other Information | 54
Item 6. Exhibits | 54
Exhibits Index | 55
Signatures | 56

2

Index
Definitions
The following abbreviations and acronyms used in this Form 10-Q are defined below:

Abbreviation or Acronym |
2024 Annual Report | Company's Annual Report on Form 10-K for the year ended December 31, 2024
AFUDC | Allowance for funds used during construction
Applied Digital | Applied Digital Corporation
ASC | FASB Accounting Standards Codification
ASU | FASB Accounting Standards Update
ATM | At-the-Market
Cascade | Cascade Natural Gas Corporation, an indirect wholly-owned subsidiary of MDU Energy Capital
Centennial | CEHI, LLC, a direct wholly-owned subsidiary of the Company, formerly known as Centennial Energy Holdings, Inc., prior to the separation of Knife River from the Company. References to Centennial's historical business and operations refer to the business and operations of Centennial Energy Holdings, Inc.
Centennial Capital | Centennial Holdings Capital LLC, a direct wholly-owned subsidiary of Centennial
CODM | Chief Operating Decision Maker
Company | MDU Resources Group, Inc.
COVID-19 | Coronavirus disease 2019
Coyote Creek | Coyote Creek Mining Company, LLC, a subsidiary of The North American Coal Corporation
Coyote Station | 427-MW coal-fired electric generating facility near Beulah, North Dakota (25 percent ownership)
CWIP | Construction work in progress, costs associated with the construction of new utility facilities recorded on the balance sheet until these facilities are placed in service
dk | Decatherm
EDA | Equity Distribution Agreement
Eighth Circuit | United States Court of Appeals for the Eighth Circuit
EPA | United States Environmental Protection Agency
Everus | Everus Construction Group, Inc., a wholly-owned subsidiary of the Company prior to the separation from the Company, that was established in conjunction with the proposed separation of Everus Construction
Everus Construction | Everus Construction, Inc., a direct wholly-owned subsidiary of Centennial prior to the separation from the Company, formerly known as MDU Construction Services Group, Inc. prior to March 12, 2024
Exchange Act | Securities Exchange Act of 1934, as amended
FASB | Financial Accounting Standards Board
FERC | Federal Energy Regulatory Commission
Fidelity | Fidelity Exploration & Production Company, an indirect wholly-owned subsidiary of Centennial (previously referred to as the Company's exploration and production segment)
FSA | Forward sale agreement
GAAP | Accounting principles generally accepted in the United States of America
GHG | Greenhouse gas
Holding Company Reorganization | The internal holding company reorganization completed on January 1, 2019, pursuant to the agreement and plan of merger, dated as of December 31, 2018, by and among Montana-Dakota, the Company and MDUR Newco Sub, which resulted in the Company becoming a holding company and owning all of the outstanding capital stock of Montana-Dakota
Intermountain | Intermountain Gas Company, an indirect wholly-owned subsidiary of MDU Energy Capital
IPUC | Idaho Public Utilities Commission
IRA | Inflation Reduction Act of 2022
IRP | Integrated Resource Plan

3

Index

JETx | 345-kV transmission line from Jamestown, North Dakota to Ellendale, North Dakota (50 percent ownership)
kWh | Kilowatt-hour
kV | Kilovolt
MAOP | Maximum allowable operating pressure
MDU Energy Capital | MDU Energy Capital, LLC, a direct wholly-owned subsidiary of the Company
MDUR Newco | MDUR Newco, Inc., a public holding company created by implementing the Holding Company Reorganization, now known as the Company
MDUR Newco Sub | MDUR Newco Sub, Inc., a direct, wholly-owned subsidiary of MDUR Newco, which was merged with and into Montana-Dakota in the Holding Company Reorganization
MISO | Midcontinent Independent System Operator, Inc., the organization that provides open-access transmission services and monitors the high-voltage transmission system in the Midwest United States and Manitoba, Canada and a southern United States region which includes much of Arkansas, Mississippi, and Louisiana
MMcf | Million cubic feet
MMdk | Million dk
Montana-Dakota | Montana-Dakota Utilities Co., a direct wholly-owned subsidiary of MDU Energy Capital
MTPSC | Montana Public Service Commission
MW | Megawatt
NDDEQ | North Dakota Department of Environmental Quality
NDPSC | North Dakota Public Service Commission
NERC | North American Electric Reliability Corporation
NPA | Note Purchase Agreement
OBBBA | One Big Beautiful Bill Act
ODEQ | Oregon Department of Environmental Quality
OPUC | Oregon Public Utility Commission
PHMSA | Pipeline and Hazardous Materials Safety Administration
RNG | Renewable natural gas
SBCC | State Building Code Council
SDPUC | South Dakota Public Utilities Commission
SOFR | Secured Overnight Financing Rate
SEC | United States Securities and Exchange Commission
Securities Act | Securities Act of 1933, as amended
SPP | Southwest Power Pool, the organization that manages the electric grid and wholesale power market for the central United States
TSA | In connection with the separation of Everus, the Company and Everus entered into a Transition Services Agreement whereby each party will provide certain post-separation services on a transitional basis
VIE | Variable interest entity
Washington DOE | Washington State Department of Ecology
WBI Energy | WBI Energy, Inc., an indirect wholly-owned subsidiary of Centennial
WBI Energy Transmission | WBI Energy Transmission, Inc., an indirect wholly-owned subsidiary of Centennial
WYPSC | Wyoming Public Service Commission

4

Index
Introduction
Montana-Dakota was incorporated under the state laws of Delaware in 1924. The Company was incorporated under the state laws of Delaware in 2018. Upon the completion of the Holding Company Reorganization, Montana-Dakota became a subsidiary of the Company. Its principal executive offices are located at 1200 West Century Avenue, P.O. Box 5650, Bismarck, North Dakota 58506-5650, telephone (701) 530-1000.
Through a strategy focusing on its "CORE," the Company strives to deliver superior value and achieve industry-leading performance as a pure-play regulated energy delivery company, while pursuing organic growth opportunities. The Company's "CORE" strategy prioritizes customers and communities, operational excellence, returns focused initiatives and an employee driven culture. The Company generates, transmits and distributes electricity and provides natural gas distribution, transportation and storage services. These businesses are regulated by state public service commissions and/or the FERC.
On October 31, 2024, the Company completed the separation of Everus, its former construction services business, resulting in Everus becoming an independent, publicly-traded company. The Company's board of directors approved the distribution of all the outstanding shares of Everus common stock to the Company's stockholders. Stockholders of the Company received one share of Everus common stock for every four shares of the Company's common stock held as of the close of business on October 21, 2024, the record date for the distribution. The separation of Everus was a tax-free spinoff transaction to the Company's stockholders for U.S. federal income tax purposes, except for cash received in lieu of fractional shares. The historical results of operation for Everus are presented as discontinued operations, net of tax, in the Company's Consolidated Financial Statements, except for allocated general corporate overhead costs of the Company, which did not meet the criteria for discontinued operations and are reflected in Other.
As of September 30, 2025, the Company was organized into three reportable business segments. These business segments include: electric, natural gas distribution and pipeline. The Company's business segments are determined based on the Company's method of internal reporting, which generally segregates the business activities by differences in products and services. The internal reporting of these segments is defined based on the reporting and review process used by the Company's CODM.
The Company, through its wholly-owned subsidiary, MDU Energy Capital, owns Montana-Dakota, Cascade and Intermountain. The electric segment is comprised of Montana-Dakota while the natural gas distribution segment is comprised of Montana-Dakota, Cascade and Intermountain.
The Company, through its wholly-owned subsidiary, Centennial, owns WBI Energy and Centennial Capital. WBI Energy is the pipeline segment and Centennial Capital is reflected in the Other category.
For more information on the Company's business segments, see Note 15 of the Notes to Consolidated Financial Statements.
5

Index
Part I -- Financial Information
Item 1. Financial Statements

MDU Resources Group, Inc.
Consolidated Statements of Income
(Unaudited)
| Three Months Ended | Nine Months Ended
| September 30, | September 30,
| 2025 | 2024 | 2025 | 2024
| (In thousands, except per share amounts)
Operating revenues | $ | 315,036 |  | $ | 289,694 |  | $ | 1,341,055 |  | $ | 1,222,440 |
Operating expenses: |  |  |  |
Purchased natural gas sold | 58,514 |  | 53,377 |  | 471,728 |  | 406,569 |
Electric fuel and purchased power | 41,098 |  | 32,576 |  | 119,737 |  | 108,991 |
Operation and maintenance | 101,762 |  | 101,211 |  | 325,696 |  | 308,780 |
Depreciation and amortization | 52,046 |  | 49,835 |  | 155,160 |  | 149,292 |
Taxes, other than income | 21,776 |  | 17,849 |  | 85,699 |  | 77,731 |
Total operating expenses | 275,196 |  | 254,848 |  | 1,158,020 |  | 1,051,363 |
Operating income | 39,840 |  | 34,846 |  | 183,035 |  | 171,077 |
Other income | 7,298 |  | 8,970 |  | 22,240 |  | 31,242 |
Interest expense | 26,417 |  | 27,337 |  | 78,684 |  | 80,349 |
Income before income taxes | 20,721 |  | 16,479 |  | 126,591 |  | 121,970 |
Income taxes | 2,371 |  | 876 |  | 11,597 |  | 11,390 |
Income from continuing operations | 18,350 |  | 15,603 |  | 114,994 |  | 110,580 |
Discontinued operations, net of tax | (39) |  | 49,012 |  | (938) |  | 115,370 |
Net income | $ | 18,311 |  | $ | 64,615 |  | $ | 114,056 |  | $ | 225,950 |
Earnings per share - basic: |  |  |  |
Income from continuing operations | $ | .09 |  | $ | .08 |  | $ | .56 |  | $ | .54 |
Discontinued operations, net of tax | — |  | .24 |  | — |  | .57 |
Earnings per share - basic | $ | .09 |  | $ | .32 |  | $ | .56 |  | $ | 1.11 |
Earnings per share - diluted: |  |  |  |
Income from continuing operations | $ | .09 |  | $ | .08 |  | $ | .56 |  | $ | .54 |
Discontinued operations, net of tax | — |  | .24 |  | — |  | .57 |
Earnings per share - diluted | $ | .09 |  | $ | .32 |  | $ | .56 |  | $ | 1.11 |
Weighted average common shares outstanding - basic | 204,331 |  | 203,888 |  | 204,269 |  | 203,852 |
Weighted average common shares outstanding - diluted | 205,285 |  | 204,678 |  | 205,153 |  | 204,451 |

The accompanying notes are an integral part of these consolidated financial statements.
6

Index

MDU Resources Group, Inc.
Consolidated Statements of Comprehensive Income
(Unaudited)
|  | Three Months Ended | Nine Months Ended
|  | September 30, | September 30,
|  | 2025 | 2024 | 2025 | 2024
|  | (In thousands)
Net income |  | $ | 18,311 |  | $ | 64,615 |  | $ | 114,056 |  | $ | 225,950 |
Other comprehensive income: |  |  |  |  |
Postretirement liability adjustment: |  |  |  |  |
Amortization of postretirement liability losses included in net periodic benefit credit, net of tax of $33 and $33 for the three months ended and $85 and $101 for the nine months ended in 2025 and 2024, respectively |  | 103 |  | 104 |  | 324 |  | 311 |
Net unrealized gain on available-for-sale investments: |  |  |  |  |
Net unrealized (loss) gain on available-for-sale investments arising during the period, net of tax of $(1) and $47 for the three months ended and $22 and $45 for the nine months ended in 2025 and 2024, respectively |  | (3) |  | 177 |  | 82 |  | 170 |
Reclassification adjustment for loss on available-for-sale investments included in net income, net of tax of $1 and $1 for the three months ended and $2 and $5 for the nine months ended in 2025 and 2024, respectively |  | 3 |  | 3 |  | 9 |  | 16 |
Net unrealized gain on available-for-sale investments |  | — |  | 180 |  | 91 |  | 186 |
Other comprehensive income |  | 103 |  | 284 |  | 415 |  | 497 |
Comprehensive income attributable to common stockholders |  | $ | 18,414 |  | $ | 64,899 |  | $ | 114,471 |  | $ | 226,447 |

The accompanying notes are an integral part of these consolidated financial statements.
7

Index

MDU Resources Group, Inc.
Consolidated Balance Sheets
(Unaudited)
| September 30, 2025 | September 30, 2024 | December 31, 2024
Assets | (In thousands, except shares and per share amounts)
Current assets: |  |  |
Cash, cash equivalents and restricted cash | $ | 75,853 |  | $ | 88,282 |  | $ | 66,904 |
Receivables, net | 132,240 |  | 128,241 |  | 274,303 |
Current regulatory assets | 179,149 |  | 241,008 |  | 215,436 |
Inventories | 44,272 |  | 44,966 |  | 44,940 |
Prepayments and other current assets | 69,853 |  | 76,478 |  | 64,676 |
Current assets of discontinued operations | — |  | 888,845 |  | — |
Total current assets | 501,367 |  | 1,467,820 |  | 666,259 |
Noncurrent assets: |  |  |
Property, plant and equipment | 7,863,725 |  | 7,420,616 |  | 7,554,063 |
Less accumulated depreciation and amortization | 2,272,380 |  | 2,169,271 |  | 2,209,771 |
Net property, plant and equipment | 5,591,345 |  | 5,251,345 |  | 5,344,292 |
Goodwill | 345,736 |  | 345,736 |  | 345,736 |
Regulatory assets | 305,890 |  | 343,578 |  | 322,350 |
Investments | 118,443 |  | 112,954 |  | 115,459 |
Other | 322,959 |  | 258,456 |  | 244,722 |
Noncurrent assets of discontinued operations | — |  | 392,760 |  | — |
Total noncurrent assets | 6,684,373 |  | 6,704,829 |  | 6,372,559 |
Total assets | $ | 7,185,740 |  | $ | 8,172,649 |  | $ | 7,038,818 |
Liabilities and Stockholders' Equity |  |  |
Current liabilities: |  |  |
Long-term debt due within one year | $ | 164,700 |  | $ | 86,777 |  | $ | 161,700 |
Accounts payable | 122,109 |  | 106,503 |  | 150,070 |
Regulatory liabilities due within one year | 143,822 |  | 157,068 |  | 137,167 |
Taxes payable | 43,328 |  | 47,873 |  | 43,372 |
Dividends payable | 28,606 |  | 26,024 |  | 26,511 |
Accrued compensation | 31,628 |  | 30,082 |  | 35,264 |
Other accrued liabilities | 132,356 |  | 148,630 |  | 124,514 |
Current liabilities of discontinued operations | — |  | 678,418 |  | — |
Total current liabilities | 666,549 |  | 1,281,375 |  | 678,598 |
Noncurrent liabilities: |  |  |
Long-term debt | 2,188,485 |  | 2,233,520 |  | 2,130,910 |
Deferred income taxes | 434,099 |  | 452,513 |  | 441,320 |
Regulatory liabilities | 473,812 |  | 463,790 |  | 459,170 |
Asset retirement obligations | 419,616 |  | 397,952 |  | 406,351 |
Other | 280,085 |  | 228,545 |  | 231,895 |
Noncurrent liabilities of discontinued operations | — |  | 56,969 |  | — |
Total noncurrent liabilities | 3,796,097 |  | 3,833,289 |  | 3,669,646 |
Commitments and contingencies |  |  |
Stockholders' equity: |  |  |
Common stock Authorized - 500,000,000 shares, $1.00 par value Shares issued - 204,331,170 at September 30, 2025, 203,888,237 at September 30, 2024 and 203,934,578 at December 31, 2024 | 204,331 |  | 203,888 |  | 203,935 |
Other paid-in capital | 1,473,739 |  | 1,470,429 |  | 1,473,738 |
Retained earnings | 1,061,407 |  | 1,401,555 |  | 1,029,699 |
Accumulated other comprehensive loss | (16,383) |  | (17,887) |  | (16,798) |
Total stockholders' equity | 2,723,094 |  | 3,057,985 |  | 2,690,574 |
Total liabilities and stockholders' equity | $ | 7,185,740 |  | $ | 8,172,649 |  | $ | 7,038,818 |

The accompanying notes are an integral part of these consolidated financial statements.
8

Index

MDU Resources Group, Inc.
Consolidated Statements of Equity
(Unaudited)
|  |  | Other Paid-in Capital | Retained Earnings | Accumu-lated Other Compre-hensive Loss |
| Common Stock |
| Shares | Amount | Total
| (In thousands, except shares)
At December 31, 2024 | 203,934,578 |  | $ | 203,935 |  | $ | 1,473,738 |  | $ | 1,029,699 |  | $ | (16,798) |  | $ | 2,690,574 |
Net income | — |  | — |  | — |  | 81,965 |  | — |  | 81,965 |
Other comprehensive income | — |  | — |  | — |  | — |  | 192 |  | 192 |
Dividends declared on common stock | — |  | — |  | — |  | (26,765) |  | — |  | (26,765) |
Stock-based compensation | — |  | — |  | 1,646 |  | — |  | — |  | 1,646 |
Issuance of common stock upon vesting of stock-based compensation, net of shares used for tax withholdings | 396,592 |  | 396 |  | (4,872) |  | — |  | — |  | (4,476) |
At March 31, 2025 | 204,331,170 |  | $ | 204,331 |  | $ | 1,470,512 |  | $ | 1,084,899 |  | $ | (16,606) |  | $ | 2,743,136 |
Net income | — |  | — |  | — |  | 13,780 |  | — |  | 13,780 |
Other comprehensive income | — |  | — |  | — |  | — |  | 120 |  | 120 |
Dividends declared on common stock | — |  | — |  | — |  | (26,770) |  | — |  | (26,770) |
Stock-based compensation | — |  | — |  | 1,638 |  | — |  | — |  | 1,638 |
At June 30, 2025 | 204,331,170 |  | $ | 204,331 |  | $ | 1,472,150 |  | $ | 1,071,909 |  | $ | (16,486) |  | $ | 2,731,904 |
Net income | — |  | — |  | — |  | 18,311 |  | — |  | 18,311 |
Other comprehensive income | — |  | — |  | — |  | — |  | 103 |  | 103 |
Dividends declared on common stock | — |  | — |  | — |  | (28,813) |  | — |  | (28,813) |
Stock-based compensation | — |  | — |  | 1,636 |  | — |  | — |  | 1,636 |
Costs of issuance of common stock | — |  | — |  | (47) |  | — |  | — |  | (47) |
At September 30, 2025 | 204,331,170 |  | $ | 204,331 |  | $ | 1,473,739 |  | $ | 1,061,407 |  | $ | (16,383) |  | $ | 2,723,094 |

The accompanying notes are an integral part of these consolidated financial statements.
9

Index

MDU Resources Group, Inc.
Consolidated Statements of Equity
(Unaudited)
|  | Other Paid-in Capital | Retained Earnings | Accumu-lated Other Compre-hensive Loss |
| Common Stock |
| Shares | Amount | Total
| (In thousands, except shares)
At December 31, 2023 | 203,689,090 |  | $ | 203,689 |  | $ | 1,466,235 |  | $ | 1,253,693 |  | $ | (18,384) |  | $ | 2,905,233 |
Net income | — |  | — |  | — |  | 100,898 |  | — |  | 100,898 |
Other comprehensive income | — |  | — |  | — |  | — |  | 74 |  | 74 |
Dividends declared on common stock | — |  | — |  | — |  | (25,779) |  | — |  | (25,779) |
Stock-based compensation | — |  | — |  | 3,173 |  | — |  | — |  | 3,173 |
Costs of issuance of common stock | — |  | — |  | (35) |  | — |  | — |  | (35) |
Issuance of common stock upon vesting of stock-based compensation, net of shares used for tax withholdings | 199,147 |  | 199 |  | (2,822) |  | — |  | — |  | (2,623) |
At March 31, 2024 | 203,888,237 |  | $ | 203,888 |  | $ | 1,466,551 |  | $ | 1,328,812 |  | $ | (18,310) |  | $ | 2,980,941 |
Net income | — |  | — |  | — |  | 60,436 |  | — |  | 60,436 |
Other comprehensive income | — |  | — |  | — |  | — |  | 139 |  | 139 |
Dividends declared on common stock | — |  | — |  | — |  | (25,644) |  | — |  | (25,644) |
Stock-based compensation | — |  | — |  | 1,947 |  | — |  | — |  | 1,947 |
Costs of issuance of common stock | — |  | — |  | (15) |  | — |  | — |  | (15) |
At June 30, 2024 | 203,888,237 |  | $ | 203,888 |  | $ | 1,468,483 |  | $ | 1,363,604 |  | $ | (18,171) |  | $ | 3,017,804 |
Net income | — |  | — |  | — |  | 64,615 |  | — |  | 64,615 |
Other comprehensive income | — |  | — |  | — |  | — |  | 284 |  | 284 |
Dividends declared on common stock | — |  | — |  | — |  | (26,664) |  | — |  | (26,664) |
Stock-based compensation | — |  | — |  | 1,946 |  | — |  | — |  | 1,946 |
At September 30, 2024 | 203,888,237 |  | $ | 203,888 |  | $ | 1,470,429 |  | $ | 1,401,555 |  | $ | (17,887) |  | $ | 3,057,985 |

The accompanying notes are an integral part of these consolidated financial statements.
10

Index

MDU Resources Group, Inc. |
Consolidated Statements of Cash Flows |
(Unaudited) |
| Nine Months Ended |
| September 30, |
| 2025 | 2024 |
| (In thousands) |
Operating activities: |  |  |
Net income | $ | 114,056 |  | $ | 225,950 |  |
(Loss) income from discontinued operations, net of tax | (938) |  | 115,370 |  |
Income from continuing operations | 114,994 |  | 110,580 |  |
Adjustments to reconcile net income to net cash provided by operating activities: |  |  |
Depreciation and amortization | 155,160 |  | 149,292 |  |
Deferred income taxes | (12,473) |  | (6,719) |  |
Provision for credit losses | 5,404 |  | 4,953 |  |
Amortization of debt issuance costs | 928 |  | 1,167 |  |
Employee stock-based compensation costs | 4,920 |  | 6,033 |  |
Pension and postretirement benefit plan net periodic benefit credit | (802) |  | (2,882) |  |
Unrealized gains on investments | (4,772) |  | (5,282) |  |
Changes in current assets and liabilities, net of acquisitions: |  |  |
Receivables | 136,261 |  | 128,063 |  |
Inventories | (603) |  | (2,092) |  |
Other current assets | 47,598 |  | 39,312 |  |
Accounts payable | (47,736) |  | (60,145) |  |
Other current liabilities | 13,815 |  | 16,311 |  |
Pension and postretirement benefit plan contributions | (2,807) |  | (2,799) |  |
Other noncurrent changes | (16,354) |  | (23,249) |  |
Net cash provided by continuing operations | 393,533 |  | 352,543 |  |
Net cash (used in) provided by discontinued operations | (740) |  | 89,243 |  |
Net cash provided by operating activities | 392,793 |  | 441,786 |  |
Investing activities: |  |  |
Capital expenditures | (353,804) |  | (366,483) |  |
Cost of removal, net of salvage value | (7,653) |  | (6,130) |  |
Investments | (3,288) |  | (3,308) |  |
Proceeds from investment excess cash and cost basis withdrawal | 5,000 |  | 9,000 |  |
Net cash used in continuing operations | (359,745) |  | (366,921) |  |
Net cash used in discontinued operations | — |  | (25,489) |  |
Net cash used in investing activities | (359,745) |  | (392,410) |  |
Financing activities: |  |  |
Repayment of short-term borrowings | — |  | (95,000) |  |
Issuance of long-term debt | 123,100 |  | 302,400 |  |
Repayment of long-term debt | (62,812) |  | (147,731) |  |
Debt issuance costs | (226) |  | (2,416) |  |
Costs of issuance of common stock | (47) |  | (50) |  |
Dividends paid | (79,638) |  | (76,915) |  |
Tax withholding on stock-based compensation | (4,476) |  | (2,623) |  |
Net cash used in continuing operations | (24,099) |  | (22,335) |  |
Net cash used in discontinued operations | — |  | — |  |
Net cash used in financing activities | (24,099) |  | (22,335) |  |
(Decrease) increase in cash, cash equivalents and restricted cash | 8,949 |  | 27,041 |  |
Cash, cash equivalents and restricted cash - beginning of year | 66,904 |  | 76,975 |  |
Cash, cash equivalents and restricted cash - end of period * | $ | 75,853 |  | $ | 104,016 |  |
*Includes cash of discontinued operations of $15.7 million at September 30, 2024. |

The accompanying notes are an integral part of these consolidated financial statements.
11

Index
MDU Resources Group, Inc.
Notes to Consolidated
Financial Statements
September 30, 2025 and 2024
(Unaudited)
Note 1 - Basis of presentation
The accompanying consolidated interim financial statements were prepared in accordance with GAAP for interim financial information and with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X. Interim financial statements do not include all disclosures provided in annual financial statements and, accordingly, these financial statements should be read in conjunction with those appearing in the 2024 Annual Report. The information is unaudited but includes all adjustments that are, in the opinion of management, necessary for a fair presentation of the accompanying consolidated interim financial statements and are of a normal recurring nature. Depreciation and amortization expense is reported separately on the Consolidated Statements of Income and therefore is excluded from the other line items within operating expenses.
On October 31, 2024, the Company completed the separation of Everus, its former construction services business, resulting in Everus becoming an independent, publicly-traded company. The Company's board of directors approved the distribution of all the outstanding shares of Everus common stock to the Company's stockholders. Stockholders of the Company received one share of Everus common stock for every four shares of the Company's common stock held as of the close of business on October 21, 2024, the record date for the distribution. The separation of Everus was a tax-free spinoff transaction to the Company's stockholders for U.S. federal income tax purposes, except for cash received in lieu of fractional shares.
The Company's consolidated financial statements and accompanying notes for the current and prior periods have been restated to present the results of operations and the assets and liabilities of Everus as discontinued operations, other than certain corporate overhead costs of the Company historically allocated to Everus, which are reflected in Other. Also included in discontinued operations in the Consolidated Statements of Income are the supporting activities of Fidelity and certain interest expense related to financing activity associated with the Everus separation. The assets and liabilities of the Company's discontinued operations are included in current assets of discontinued operations, noncurrent assets of discontinued operations, current liabilities of discontinued operations and noncurrent liabilities of discontinued operations on the Consolidated Balance Sheets. Unless otherwise indicated, the amounts presented in the accompanying notes to the consolidated financial statements relate to the Company's continuing operations. For more information on discontinued operations, see Note 3.
Additionally, certain amounts recorded in prior year financial statements have been reclassified to conform to the current year presentation. The Company has reclassified $7.3 million and $21.4 million of transmission-related expenses from operation and maintenance to electric fuel and purchased power for the three and nine months ended September 30, 2024, respectively, in the Consolidated Statements of Income. These transmission-related expenses are an integral component of the cost of electricity sold to customers and therefore, more appropriately reflected in electric fuel and purchased power than operation and maintenance expense. These reclassifications had no effect on previously reported results of operations or cash flows.
Management has also evaluated the impact of events occurring after September 30, 2025, up to the date of issuance of these consolidated interim financial statements on November 10, 2025, that would require recognition or disclosure in the Consolidated Financial Statements.
12

Index
Note 2 - New accounting standards
The following table provides a brief description of the accounting pronouncements applicable to the Company and the potential impact on its financial statements and/or disclosures:

Standard | Description | Effective date | Impact on financial statements/disclosures
Recently issued accounting standards not yet adopted
ASU 2023-09 Income Taxes - Improvements to Income Tax Disclosures an Amendment, December 2023 | In December 2023, the FASB issued guidance to address investors requests for more transparency about income tax information through improvements to income tax disclosures primarily related to the rate reconciliation and income taxes paid information and effectiveness of income tax disclosures. | Effective for annual reporting periods beginning after 2024 on a prospective basis. | The Company has evaluated and does not expect a material impact on its disclosures for the year ended December 31, 2025.
ASU 2024-01 Compensation - Stock Compensation | In March 2024, the FASB issued improvements to GAAP through an example to demonstrate application of the scope of paragraph 718-10-15-3 to determine whether profits interest and similar awards should be accounted in Compensation - Stock Compensation. | Effective for fiscal years beginning after December 15, 2024. | The Company has evaluated and does not expect a material impact on its disclosures for the year ended December 31, 2025.
ASU 2024-03 Disaggregation of Income Statement Expenses | In November 2024, the FASB issued guidance to improve the disclosures about a public business entity's expenses and address requests from investors for more detailed information about the types of expenses (including purchases of inventory, employee compensation, depreciation, amortization, and depletion) in commonly presented expense captions (such as cost of sales, selling, general, and administrative; and research and development). | Effective for annual reporting periods beginning after December 15, 2026, and interim reporting periods beginning after December 15, 2027. | The Company is currently evaluating the impact the guidance will have on its disclosures for the year ended December 31, 2027.

Note 3 - Discontinued operations
On October 31, 2024, the Company completed the separation of Everus, its former construction services segment, into a new independent, publicly-traded company. The Company's board of directors approved the distribution of all the outstanding shares of Everus common stock to the Company's stockholders. Stockholders of the Company received one share of Everus common stock for every four shares of the Company's common stock held as of the close of business on October 21, 2024, the record date for the distribution. The separation of Everus was a tax-free spinoff transaction to the Company's stockholders for U.S. federal income tax purposes, except for cash received in lieu of fractional shares.
As a result of the separation, the historical results of operations are shown in discontinued operations, net of tax, except for allocated general corporate overhead costs of the Company, which did not meet the criteria for discontinued operations. The Company’s consolidated financial statements and accompanying notes for prior periods have been restated.
The Company provided and will provide to Everus and Everus provided and will provide to the Company transition services in accordance with the TSA entered into on October 31, 2024. For the three and nine months ended September 30, 2025, the Company received $1.3 million and $6.8 million, respectively, and paid $17,000 and $42,000, respectively, for these related activities. The majority of the transition services are expected to be provided for a period of approximately eighteen months, however, no longer than two years after the separation.
Separation related costs of $39,000 and $586,000, net of tax, were incurred during the three and nine months ended September 30, 2025, respectively. Separation related costs of $1.9 million and $9.2 million, net of tax, were incurred during the three and nine months ended September 30, 2024, respectively. Separation costs incurred are presented in Discontinued operations, net of tax in the Consolidated Statements of Income. These charges primarily relate to transaction and third-party support costs, one-time business separation fees and related tax charges.
13

Index
The Company had no assets or liabilities related to the discontinued operations of Everus on its balance sheet as of September 30, 2025 or December 31, 2024. The carrying amounts of the major classes of assets and liabilities of discontinued operations included in the Company's Consolidated Balance Sheet at September 30, 2024 were as follows:

| September 30, 2024
Assets | (In Thousands)
Current assets: |
Cash, cash equivalents and restricted cash | $ | 15,734 |
Receivables, net | 806,233 |
Inventories | 46,923 |
Prepayments and other current assets | 19,955 |
Total current assets of discontinued operations | 888,845 |
Noncurrent assets: |
Net property, plant and equipment | 129,361 |
Goodwill | 143,224 |
Other intangible assets, net | 466 |
Investments | 17,648 |
Operating lease right-of-use assets | 68,852 |
Other | 33,209 |
Total noncurrent assets of discontinued operations | 392,760 |
Total assets of discontinued operations | $ | 1,281,605 |
Liabilities |
Current liabilities: |
Long-term debt due within one year | $ | 132,000 |
Accounts payable | 382,597 |
Taxes payable | 14,006 |
Accrued compensation | 66,960 |
Operating lease liabilities due within one year | 26,110 |
Other accrued liabilities | 56,745 |
Total current liabilities of discontinued operations | 678,418 |
Noncurrent liabilities: |
Deferred income taxes | 642 |
Operating lease liabilities | 43,247 |
Other | 13,080 |
Total noncurrent liabilities of discontinued operations | 56,969 |
Total liabilities of discontinued operations | $ | 735,387 |

The reconciliation of the major classes of income and expense constituting pretax loss from discontinued operations to the after-tax loss from discontinued operations on the Consolidated Statements of Income were as follows:

| Three Months Ended | Nine Months Ended
| September 30, | September 30,
| 2025 | 2024 | 2025 | 2024
| (In thousands)
Operating revenues | $ | — |  | $ | 760,822 |  | $ | 2 |  | $ | 2,089,446 |
Operating expenses | 52 |  | 705,135 |  | 1,195 |  | 1,944,457 |
Operating (loss) income | (52) |  | 55,687 |  | (1,193) |  | 144,989 |
Other income | — |  | 4,868 |  | — |  | 11,044 |
Interest expense | — |  | 2,128 |  | — |  | 6,431 |
(Loss) income from discontinued operations before income taxes | (52) |  | 58,427 |  | (1,193) |  | 149,602 |
Income tax (benefit) expense | (13) |  | 9,415 |  | (255) |  | 34,232 |
Discontinued operations, net of tax | $ | (39) |  | $ | 49,012 |  | $ | (938) |  | $ | 115,370 |

14

Index
Note 4 - Seasonality of operations
Some of the Company's operations are highly seasonal and revenues from, and certain expenses for, such operations may fluctuate significantly among quarterly periods. Accordingly, the interim results for particular businesses, and for the Company as a whole, may not be indicative of results for the full fiscal year.
Note 5 - Receivables and allowance for expected credit losses
Receivables consist primarily of trade receivables from the sale of goods and services net of expected credit losses. The Company's trade receivables are all due in 12 months or less.
The Company's expected credit losses are determined through a review using historical credit loss experience, changes in asset specific characteristics, current conditions and reasonable and supportable future forecasts, among other specific account data, and is performed at least quarterly. The Company develops and documents its methodology to determine its allowance for expected credit losses at each of its reportable business segments. Risk characteristics used by the business segments may include customer mix, knowledge of customers and general economic conditions of the various local economies, among others. Specific account balances are written off when management determines the amounts to be uncollectible. Management has reviewed the balance reserved through the allowance for expected credit losses and believes it is reasonable.
Details of the Company's expected credit losses were as follows:

| Electric | Natural gas distribution | Pipeline | Total
| (In thousands)
At December 31, 2024 | $ | 473 |  | $ | 1,366 |  | $ | — |  | $ | 1,839 |
Current expected credit loss provision | 939 |  | 2,213 |  | — |  | 3,152 |
Less write-offs charged against the allowance | 1,036 |  | 1,269 |  | — |  | 2,305 |
Credit loss recoveries collected | 166 |  | 252 |  | — |  | 418 |
At March 31, 2025 | $ | 542 |  | $ | 2,562 |  | $ | — |  | $ | 3,104 |
Current expected credit loss provision | 178 |  | (151) |  | — |  | 27 |
Less write-offs charged against the allowance | 333 |  | 1,002 |  | — |  | 1,335 |
Credit loss recoveries collected | 74 |  | 165 |  | — |  | 239 |
At June 30, 2025 | $ | 461 |  | $ | 1,574 |  | $ | — |  | $ | 2,035 |
Current expected credit loss provision | 646 |  | 1,579 |  | — |  | 2,225 |
Less write-offs charged against the allowance | 688 |  | 2,454 |  | — |  | 3,142 |
Credit loss recoveries collected | 76 |  | 220 |  | — |  | 296 |
At September 30, 2025 | $ | 495 |  | $ | 919 |  | $ | — |  | $ | 1,414 |

| Electric | Natural gas distribution | Pipeline | Total
| (In thousands)
At December 31, 2023 | $ | 414 |  | $ | 1,189 |  | $ | — |  | $ | 1,603 |
Current expected credit loss provision | 782 |  | 1,916 |  | — |  | 2,698 |
Less write-offs charged against the allowance | 659 |  | 1,455 |  | — |  | 2,114 |
Credit loss recoveries collected | 147 |  | 314 |  | — |  | 461 |
At March 31, 2024 | $ | 684 |  | $ | 1,964 |  | $ | — |  | $ | 2,648 |
Current expected credit loss provision | 190 |  | 215 |  | — |  | 405 |
Less write-offs charged against the allowance | 463 |  | 969 |  | — |  | 1,432 |
Credit loss recoveries collected | 80 |  | 196 |  | — |  | 276 |
At June 30, 2024 | $ | 491 |  | $ | 1,406 |  | $ | — |  | $ | 1,897 |
Current expected credit loss provision | 520 |  | 1,330 |  | — |  | 1,850 |
Less write-offs charged against the allowance | 594 |  | 2,121 |  | — |  | 2,715 |
Credit loss recoveries collected | 86 |  | 255 |  | — |  | 341 |
At September 30, 2024 | $ | 503 |  | $ | 870 |  | $ | — |  | $ | 1,373 |

15

Index
Note 6 - Inventories and natural gas in storage
Natural gas in storage is generally valued at lower of cost or market using the last-in, first-out method or lower of cost or net realizable value using the average cost or first-in, first-out method. The majority of all other inventories are valued at the lower of cost or net realizable value using the average cost method. The portion of the cost of natural gas in storage expected to be used within 12 months was included in inventories. Inventories on the Consolidated Balance Sheets were as follows:

| September 30, 2025 | September 30, 2024 | December 31, 2024
| (In thousands)
Natural gas in storage (current) | $ | 40,077 |  | $ | 40,770 |  | $ | 40,073 |
Fuel stock | 4,195 |  | 4,196 |  | 4,867 |
Total | $ | 44,272 |  | $ | 44,966 |  | $ | 44,940 |

The remainder of natural gas in storage, which largely represents the cost of gas required to maintain pressure levels for normal operating purposes, was included in noncurrent assets - other and was $48.5 million, $50.1 million and $48.5 million at September 30, 2025 and 2024 and December 31, 2024, respectively.
Note 7 - Earnings per share
Basic earnings per share is computed by dividing net income by the weighted average number of shares of common stock outstanding during the applicable period. Diluted earnings per share is computed by dividing net income by the total of the weighted average number of shares of common stock outstanding during the applicable period, plus the effect of non-vested performance share awards and restricted stock units. Net income was the same for both the basic and diluted earnings per share calculations. A reconciliation of the weighted average common shares outstanding used in the basic and diluted earnings per share calculations follows:

| Three Months Ended | Nine Months Ended
| September 30, | September 30,
| 2025 | 2024 | 2025 | 2024
| (In thousands, except per share amounts)
Weighted average common shares outstanding - basic | 204,331 |  | 203,888 |  | 204,269 |  | 203,852 |
Effect of dilutive performance share awards and restricted stock units | 954 |  | 790 |  | 884 |  | 599 |
Weighted average common shares outstanding - diluted | 205,285 |  | 204,678 |  | 205,153 |  | 204,451 |
Earnings per share - basic: |  |  |  |
Income from continuing operations | $ | .09 |  | $ | .08 |  | $ | .56 |  | $ | .54 |
Discontinued operations, net of tax | — |  | .24 |  | — |  | .57 |
Earnings per share - basic | $ | .09 |  | $ | .32 |  | $ | .56 |  | $ | 1.11 |
Earnings per share - diluted: |  |  |  |
Income from continuing operations | $ | .09 |  | $ | .08 |  | $ | .56 |  | $ | .54 |
Discontinued operations, net of tax | — |  | .24 |  | — |  | .57 |
Earnings per share - diluted | $ | .09 |  | $ | .32 |  | $ | .56 |  | $ | 1.11 |
Shares excluded from the calculation of diluted earnings per share | — |  | — |  | — |  | — |
Dividends declared per common share | $ | .1400 |  | $ | .1300 |  | $ | .4000 |  | $ | .3800 |

Note 8 - Equity
At-the-Market Offering Program On August 7, 2025, the Company entered into an EDA pursuant to which it may issue, offer, and sell, from time to time, up to an aggregate gross sales price of $400.0 million of shares of its common stock through an ATM offering program, which includes the ability to enter into FSAs. Since the establishment of the ATM offering program, the Company did not issue common stock pursuant to the EDA nor enter into any FSAs.
16

Index
Note 9 - Revenue from contracts with customers
Revenue is recognized when a performance obligation is satisfied by transferring control over a product or service to a customer. Revenue is measured based on consideration specified in a contract with a customer and excludes any sales incentives and amounts collected on behalf of third parties. The Company is considered an agent for certain taxes collected from customers. As such, the Company presents revenues net of these taxes at the time of sale to be remitted to governmental authorities, including sales and use taxes.
Under ASC 606 - Revenue from Contracts with Customers, the Company elected the practical expedient to recognize the incremental costs of obtaining a contract as an expense when incurred if the amortization period of the asset that the Company otherwise would have recognized is 12 months or less.
The Company recognizes revenue from the sale of emissions allowances allocated under the environmental programs in certain states. The Company has the right to payment when the allowances are sold at auction. Revenue is recognized on a point in time basis within the quarter that the auction is held. The revenues associated with the sale of these allowances are deferred as a component of the respective jurisdiction’s regulatory liability for environmental compliance. For more information on the Company’s regulatory assets and liabilities, see Note 10.
Disaggregation
In the following tables, revenue is disaggregated by the type of customer or service provided. The Company believes this level of disaggregation best depicts how the nature, amount, timing and uncertainty of revenue and cash flows are affected by economic factors. The table also includes a reconciliation of the disaggregated revenue by reportable segments. For more information on the Company's business segments, see Note 15.

Three Months Ended September 30, 2025 | Electric | Natural gas distribution | Pipeline | Other | Total
| (In thousands)
Residential utility sales | $ | 35,730 |  | $ | 64,225 |  | $ | — |  | $ | — |  | $ | 99,955 |
Commercial utility sales | 52,492 |  | 45,581 |  | — |  | — |  | 98,073 |
Industrial utility sales | 9,525 |  | 7,873 |  | — |  | — |  | 17,398 |
Other utility sales | 1,949 |  | — |  | — |  | — |  | 1,949 |
Natural gas transportation | — |  | 16,292 |  | 47,239 |  | — |  | 63,531 |
Natural gas storage | — |  | — |  | 5,680 |  | — |  | 5,680 |
Other | 19,118 |  | 7,983 |  | 4,439 |  | 182 |  | 31,722 |
Intersegment eliminations | (138) |  | (92) |  | (4,269) |  | (182) |  | (4,681) |
Revenues from contracts with customers | 118,676 |  | 141,862 |  | 53,089 |  | — |  | 313,627 |
Other revenues | (1,014) |  | 2,353 |  | 70 |  | — |  | 1,409 |
Total external operating revenues | $ | 117,662 |  | $ | 144,215 |  | $ | 53,159 |  | $ | — |  | $ | 315,036 |

Three Months Ended September 30, 2024 | Electric | Natural gas distribution | Pipeline | Other | Total
| (In thousands)
Residential utility sales | $ | 37,076 |  | $ | 61,928 |  | $ | — |  | $ | — |  | $ | 99,004 |
Commercial utility sales | 46,648 |  | 37,687 |  | — |  | — |  | 84,335 |
Industrial utility sales | 9,702 |  | 6,869 |  | — |  | — |  | 16,571 |
Other utility sales | 2,045 |  | — |  | — |  | — |  | 2,045 |
Natural gas transportation | — |  | 15,279 |  | 41,936 |  | — |  | 57,215 |
Natural gas storage | — |  | — |  | 6,053 |  | — |  | 6,053 |
Other | 16,182 |  | 9,736 |  | 3,537 |  | 22 |  | 29,477 |
Intersegment eliminations | (12) |  | (31) |  | (3,924) |  | (21) |  | (3,988) |
Revenues from contracts with customers | 111,641 |  | 131,468 |  | 47,602 |  | 1 |  | 290,712 |
Other revenues | (3,173) |  | 2,122 |  | 33 |  | — |  | (1,018) |
Total external operating revenues | $ | 108,468 |  | $ | 133,590 |  | $ | 47,635 |  | $ | 1 |  | $ | 289,694 |

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Index

Nine Months Ended September 30, 2025 | Electric | Natural gas distribution | Pipeline | Other | Total
| (In thousands)
Residential utility sales | $ | 103,984 |  | $ | 453,501 |  | $ | — |  | $ | — |  | $ | 557,485 |
Commercial utility sales | 144,397 |  | 303,611 |  | — |  | — |  | 448,008 |
Industrial utility sales | 27,936 |  | 32,433 |  | — |  | — |  | 60,369 |
Other utility sales | 5,592 |  | — |  | — |  | — |  | 5,592 |
Natural gas transportation | — |  | 49,816 |  | 142,612 |  | — |  | 192,428 |
Natural gas storage | — |  | — |  | 16,882 |  | — |  | 16,882 |
Other | 53,832 |  | 43,086 |  | 10,778 |  | 540 |  | 108,236 |
Intersegment eliminations | (457) |  | (278) |  | (47,401) |  | (540) |  | (48,676) |
Revenues from contracts with customers | 335,284 |  | 882,169 |  | 122,871 |  | — |  | 1,340,324 |
Other revenues | (7,476) |  | 8,088 |  | 119 |  | — |  | 731 |
Total external operating revenues | $ | 327,808 |  | $ | 890,257 |  | $ | 122,990 |  | $ | — |  | $ | 1,341,055 |

Nine Months Ended September 30, 2024 | Electric | Natural gas distribution | Pipeline | Other | Total
| (In thousands)
Residential utility sales | $ | 107,735 |  | $ | 431,721 |  | $ | — |  | $ | — |  | $ | 539,456 |
Commercial utility sales | 129,783 |  | 264,091 |  | — |  | — |  | 393,874 |
Industrial utility sales | 32,809 |  | 30,716 |  | — |  | — |  | 63,525 |
Other utility sales | 6,046 |  | — |  | — |  | — |  | 6,046 |
Natural gas transportation | — |  | 43,194 |  | 128,979 |  | — |  | 172,173 |
Natural gas storage | — |  | — |  | 16,766 |  | — |  | 16,766 |
Other | 44,998 |  | 18,705 |  | 9,903 |  | 82 |  | 73,688 |
Intersegment eliminations | (71) |  | (108) |  | (43,249) |  | (64) |  | (43,492) |
Revenues from contracts with customers | 321,300 |  | 788,319 |  | 112,399 |  | 18 |  | 1,222,036 |
Revenues out of scope | (5,915) |  | 6,200 |  | 119 |  | — |  | 404 |
Total external operating revenues | $ | 315,385 |  | $ | 794,519 |  | $ | 112,518 |  | $ | 18 |  | $ | 1,222,440 |

Remaining performance obligations
The remaining performance obligations at the pipeline segment include firm transportation and storage contracts with fixed pricing and fixed volumes. The Company has applied the practical expedient that does not require additional disclosures for contracts with an original duration of less than 12 months, to certain firm transportation, storage and non-regulated contracts. The Company's firm transportation and storage contracts included in the remaining performance obligations have weighted average remaining durations of less than five years and two years, respectively.
At September 30, 2025, the Company's remaining performance obligations were $552.1 million. The Company expects to recognize the following revenue amounts in future periods related to these remaining performance obligations: $87.5 million within the next 12 months or less; $80.7 million within the next 13 to 24 months; and $383.9 million in 25 months or more.
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Index
Note 10 - Regulatory assets and liabilities
The following table summarizes the individual components of unamortized regulatory assets and liabilities:

| Estimated Recovery or Refund Period as of September 30, 2025 | * | September 30, 2025 | September 30, 2024 | December 31, 2024
|  |  | (In thousands)
Regulatory assets: |  |  |  |  |
Current: |  |  |  |  |
Environmental compliance programs | Up to 1 year |  | $ | 69,646 |  | $ | 80,198 |  | $ | 76,964 |
Natural gas costs recoverable through rate adjustments | Up to 1 year |  | 34,325 |  | 111,946 |  | 91,091 |
Conservation programs | Up to 1 year |  | 27,405 |  | 19,059 |  | 19,123 |
Demand cost deferral | Up to 1 year |  | 15,287 |  | 13,898 |  | 5,237 |
Decoupling mechanisms | Up to 1 year |  | 9,716 |  | 4,795 |  | 6,767 |
Electric fuel and purchased power deferral | Up to 1 year |  | 9,644 |  | 4,497 |  | 9,662 |
Cost recovery mechanisms | Up to 1 year |  | 8,606 |  | 4,332 |  | 5,114 |
Other | Up to 1 year |  | 4,520 |  | 2,283 |  | 1,478 |
|  |  | 179,149 |  | 241,008 |  | 215,436 |
Noncurrent: |  |  |  |  |
Pension and postretirement benefits | ** |  | 142,064 |  | 142,511 |  | 142,064 |
Cost recovery mechanisms | Up to 24 years |  | 68,314 |  | 82,907 |  | 76,542 |
Plant costs/asset retirement obligations | Over plant lives |  | 46,334 |  | 45,249 |  | 47,042 |
Manufactured gas plant site remediation | - |  | 27,147 |  | 25,789 |  | 27,964 |
Taxes recoverable from customers | Over plant lives |  | 12,257 |  | 12,316 |  | 12,221 |
Covid-19 deferred costs | Up to 3 years |  | 3,863 |  | 3,857 |  | 4,167 |
Long-term debt refinancing costs | Up to 36 years |  | 1,571 |  | 2,159 |  | 2,011 |
Natural gas costs recoverable through rate adjustments | - |  | — |  | 11,707 |  | — |
Electric fuel and purchased power deferral | - |  | — |  | 8,335 |  | 4,349 |
Environmental compliance programs | - |  | — |  | 2,858 |  | — |
Other | Up to 14 years |  | 4,340 |  | 5,890 |  | 5,990 |
|  |  | 305,890 |  | 343,578 |  | 322,350 |
Total regulatory assets |  |  | $ | 485,039 |  | $ | 584,586 |  | $ | 537,786 |
Regulatory liabilities: |  |  |  |  |
Current: |  |  |  |  |
Environmental compliance programs | Up to 1 year |  | $ | 84,884 |  | $ | 77,392 |  | $ | 72,387 |
Natural gas costs refundable through rate adjustments | Up to 1 year |  | 43,373 |  | 54,197 |  | 45,427 |
Provision for rate refund | Up to 1 year |  | 4,358 |  | 8,868 |  | 3,677 |
Margin sharing | Up to 1 year |  | 3,831 |  | 3,945 |  | 4,156 |
Taxes refundable to customers | Up to 1 year |  | 2,325 |  | 2,195 |  | 2,163 |
Conservation programs | Up to 1 year |  | 1,108 |  | 2,662 |  | 2,082 |
Cost recovery mechanisms | Up to 1 year |  | 154 |  | 2,634 |  | 1,720 |
Other | Up to 1 year |  | 3,789 |  | 5,175 |  | 5,555 |
|  |  | 143,822 |  | 157,068 |  | 137,167 |
Noncurrent: |  |  |  |  |
Plant removal and decommissioning costs | Over plant lives |  | 228,982 |  | 224,839 |  | 217,603 |
Taxes refundable to customers | Over plant lives |  | 177,469 |  | 184,715 |  | 185,402 |
Cost recovery mechanisms | Up to 17 years |  | 38,426 |  | 28,397 |  | 30,354 |
Accumulated deferred investment tax credit | Over plant lives |  | 21,615 |  | 17,679 |  | 18,788 |
Pension and postretirement benefits | ** |  | 4,862 |  | 6,043 |  | 4,862 |
Other | Up to 13 years |  | 2,458 |  | 2,117 |  | 2,161 |
|  |  | 473,812 |  | 463,790 |  | 459,170 |
Total regulatory liabilities |  |  | $ | 617,634 |  | $ | 620,858 |  | $ | 596,337 |
Net regulatory position |  |  | $ | (132,595) |  | $ | (36,272) |  | $ | (58,551) |

*Estimated recovery or refund period for amounts currently being recovered or refunded in rates to customers.
** Recovered as expense is incurred or cash contributions are made.

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Index
As of September 30, 2025 and 2024, and December 31, 2024, approximately $175.9 million, $178.8 million and $181.2 million, respectively, of regulatory assets were not earning a rate of return but are expected to be recovered from customers in future rates. These assets are largely comprised of the unfunded portion of pension and postretirement benefits, asset retirement obligations, certain pipeline integrity costs and the estimated future cost of manufactured gas plant site remediation.
The Company is subject to environmental compliance regulations in certain states which require natural gas distribution companies to reduce overall GHG emissions to certain thresholds as established by each applicable state. Compliance with these standards may be achieved through increased energy efficiency and conservation measures, purchased emission allowances and offsets and purchases of low carbon fuels. Emission allowances are allocated by the respective states to the Company at no cost, of which a portion is required to be sold at auction in certain states. The compliance costs for these regulations and the revenues from the sale of the allocated emissions allowances are passed through to customers in rates and the Company has, accordingly, deferred the environmental compliance costs as a regulatory asset and proceeds from the sale of allowances as a regulatory liability.
For a discussion of the Company's most recent cases by jurisdiction, see Note 17.
If, for any reason, the Company's regulated businesses cease to meet the criteria for application of regulatory accounting for all or part of their operations, the regulatory assets and liabilities relating to those portions ceasing to meet such criteria would be written off and included in the statement of income or accumulated other comprehensive loss in the period in which the discontinuance of regulatory accounting occurs.
Note 11 - Environmental allowances and obligations
The Company's natural gas distribution segment acquires environmental allowances as part of its requirement to comply with environmental regulations in certain states. Allowances are allocated by the respective states to the Company at no cost and additional allowances are required to be purchased as needed based on the requirements in the respective states. The segment records purchased and allocated environmental allowances at weighted average cost under the inventory method of accounting. Environmental allowances are included in Prepayments and other current assets and noncurrent assets - Other on the Consolidated Balance Sheets.
Environmental compliance obligations, which are based on GHG emissions, are measured at the carrying value of environmental allowances held plus the estimated value of additional allowances necessary to satisfy the compliance obligation. Environmental compliance obligations are included in current liabilities - Other accrued liabilities and noncurrent liabilities - Other on the Consolidated Balance Sheets.
The Company recognizes revenue from the sale of emissions allowances allocated under the environmental programs when the allowances are sold at auction. The revenues associated with the sale of these allowances are deferred as a component of the respective jurisdiction’s regulatory liability for environmental compliance.
As environmental allowances are surrendered, the segment reduces the associated environmental compliance assets and liabilities from the Consolidated Balance Sheets. The expenses and revenues associated with the Company’s environmental allowances and obligations are deferred as regulatory assets and liabilities and recognized as a component of purchased natural gas sold as recovered in customer rates. For more information on the Company’s regulatory assets and liabilities, see Note 10.
Note 12 - Fair value measurements
Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability (an exit price) in an orderly transaction between market participants at the measurement date. The fair value ASC establishes a hierarchy for grouping assets and liabilities, based on the significance of inputs. The estimated fair values of the Company's assets and liabilities measured on a recurring basis are determined using the market approach.
The Company measures its investments in certain fixed-income and equity securities at fair value with changes in fair value recognized in income. The Company anticipates using these investments, which consist of insurance contracts, to satisfy its obligations under its unfunded, nonqualified defined benefit and defined contribution plans for executive officers and certain key management employees and invests in these fixed-income and equity securities for the purpose of earning investment returns and capital appreciation. These investments, which totaled $66.2 million, $59.2 million and $59.3 million, at September 30, 2025 and 2024, and December 31, 2024, respectively, are classified as Investments on the Consolidated Balance Sheets. The net unrealized gain on these investments was $2.2 million and $4.8 million for the three and nine months ended September 30, 2025, respectively. The net unrealized gain on these investments was $2.4 million and $5.3 million for the three and nine months ended September 30, 2024, respectively. The change in fair value, which is considered part of the cost of the plan, is classified in Other income on the Consolidated Statements of Income. In the second quarter of 2025 the Company withdrew $5.0 million of cash in excess of 125 percent of the full funding amount, which had no effect on the cost basis of the investments held. In the first quarter of 2024 the Company withdrew $9.0 million of its cost basis, which reduced Investments on the Consolidated Balance Sheets.
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Index
The Company did not elect the fair value option, which records gains and losses in income, for its available-for-sale securities, which include mortgage-backed securities and U.S. Treasury securities. These available-for-sale securities are recorded at fair value and are classified as Investments on the Consolidated Balance Sheets. Unrealized gains or losses are recorded in Accumulated other comprehensive loss on the Consolidated Balance Sheets. Details of available-for-sale securities were as follows:

September 30, 2025 | Cost | Gross Unrealized Gains | Gross Unrealized Losses | Fair Value
| (In thousands)
Mortgage-backed securities | $ | 8,465 |  | $ | 24 |  | $ | 230 |  | $ | 8,259 |
U.S. Treasury securities | 3,495 |  | 24 |  | 3 |  | 3,516 |
Total | $ | 11,960 |  | $ | 48 |  | $ | 233 |  | $ | 11,775 |

September 30, 2024 | Cost | Gross Unrealized Gains | Gross Unrealized Losses | Fair Value
| (In thousands)
Mortgage-backed securities | $ | 8,104 |  | $ | 41 |  | $ | 312 |  | $ | 7,833 |
U.S. Treasury securities | 3,897 |  | 74 |  | — |  | 3,971 |
Total | $ | 12,001 |  | $ | 115 |  | $ | 312 |  | $ | 11,804 |

December 31, 2024 | Cost | Gross Unrealized Gains | Gross Unrealized Losses | Fair Value
| (In thousands)
Mortgage-backed securities | $ | 7,933 |  | $ | 4 |  | $ | 383 |  | $ | 7,554 |
U.S. Treasury securities | 3,945 |  | 80 |  | 1 |  | 4,024 |
Total | $ | 11,878 |  | $ | 84 |  | $ | 384 |  | $ | 11,578 |

The Company's assets measured at fair value on a recurring basis were as follows:

| Fair Value Measurements at September 30, 2025, Using |
| Quoted Prices in Active Markets for Identical Assets (Level 1) | Significant Other Observable Inputs (Level 2) | Significant Unobservable Inputs (Level 3) | Balance at September 30, 2025
| (In thousands)
Assets: |  |  |  |
Money market funds | $ | — |  | $ | 9,743 |  | $ | — |  | $ | 9,743 |
Insurance contracts* | — |  | 66,229 |  | — |  | 66,229 |
Available-for-sale securities: |  |  |  |
Mortgage-backed securities | — |  | 8,260 |  | — |  | 8,260 |
U.S. Treasury securities | — |  | 3,516 |  | — |  | 3,516 |
Total assets measured at fair value | $ | — |  | $ | 87,748 |  | $ | — |  | $ | 87,748 |

* The insurance contracts invest approximately 57 percent in fixed-income investments, 18 percent in common stock of large-cap companies, 10 percent in target date investments, 7 percent in common stock of mid-cap companies, 4 percent in common stock of small-cap companies, 3 percent in cash equivalents, and 1 percent in international investments.

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Index

| Fair Value Measurements at September 30, 2024, Using |
| Quoted Prices in Active Markets for Identical Assets (Level 1) | Significant Other Observable Inputs (Level 2) | Significant Unobservable Inputs (Level 3) | Balance at September 30, 2024
| (In thousands)
Assets: |  |  |  |
Money market funds | $ | — |  | $ | 11,033 |  | $ | — |  | $ | 11,033 |
Insurance contracts* | — |  | 59,210 |  | — |  | 59,210 |
Available-for-sale securities: |  |  |  |
Mortgage-backed securities | — |  | 7,833 |  | — |  | 7,833 |
U.S. Treasury securities | — |  | 3,971 |  | — |  | 3,971 |
Total assets measured at fair value | $ | — |  | $ | 82,047 |  | $ | — |  | $ | 82,047 |

* The insurance contracts invest approximately 55 percent in fixed-income investments, 18 percent in common stock of large-cap companies, 10 percent in target date investments, 8 percent in common stock of mid-cap companies, 4 percent in common stock of small-cap companies, 4 percent in cash equivalents, and 1 percent in international investments.

| Fair Value Measurements at December 31, 2024, Using |
| Quoted Prices in Active Markets for Identical Assets (Level 1) | Significant Other Observable Inputs (Level 2) | Significant Unobservable Inputs (Level 3) | Balance at December 31, 2024
| (In thousands)
Assets: |  |  |  |
Money market funds | $ | — |  | $ | 12,879 |  | $ | — |  | $ | 12,879 |
Insurance contracts* | — |  | 59,282 |  | — |  | 59,282 |
Available-for-sale securities: |  |  |  |
Mortgage-backed securities | — |  | 7,554 |  | — |  | 7,554 |
U.S. Treasury securities | — |  | 4,024 |  | — |  | 4,024 |
Total assets measured at fair value | $ | — |  | $ | 83,739 |  | $ | — |  | $ | 83,739 |

* The insurance contracts invest approximately 58 percent in fixed-income investments, 17 percent in common stock of large-cap companies, 8 percent in target date investments, 8 percent in common stock of mid-cap companies, 4 percent in common stock of small-cap companies, 4 percent in cash equivalents, and 1 percent in international investments.

The Company's money market funds are valued at the net asset value of shares held at the end of the period, based on published market quotations on active markets, or using other known sources including pricing from outside sources. The estimated fair value of the Company's mortgage-backed securities and U.S. Treasury securities are based on comparable market transactions, other observable inputs or other sources, including pricing from outside sources. The estimated fair value of the Company's insurance contracts are based on contractual cash surrender values that are determined primarily by investments in managed separate accounts of the insurer. These amounts approximate fair value. The managed separate accounts are valued based on other observable inputs or corroborated market data.
Though the Company believes the methods used to estimate fair value are consistent with those used by other market participants, the use of other methods or assumptions could result in a different estimate of fair value.
The Company applies the provisions of the fair value measurement standard to its nonrecurring, non-financial measurements, including long-lived asset impairments. These assets are not measured at fair value on an ongoing basis but are subject to fair value adjustments only in certain circumstances. The Company reviews the carrying value of its long-lived assets, excluding goodwill, whenever events or changes in circumstances indicate that such carrying amounts may not be recoverable.
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Index
The Company's long-term debt is not measured at fair value on the Consolidated Balance Sheets and the fair value is being provided for disclosure purposes only. The fair value was categorized as Level 2 in the fair value hierarchy and was based on discounted future cash flows using current market interest rates. The estimated fair value of the Company's Level 2 long-term debt was as follows:

| September 30, 2025 | September 30, 2024 | December 31, 2024
| (In thousands)
Carrying amount | $ | 2,353,185 |  | $ | 2,320,297 |  | $ | 2,292,610 |
Fair value | $ | 2,068,905 |  | $ | 2,075,359 |  | $ | 1,963,396 |

The carrying amounts of the Company's remaining financial instruments included in current assets and current liabilities approximate their fair values.
Note 13 - Debt
Certain debt instruments of the Company and its subsidiaries contain restrictive and financial covenants and cross-default provisions. In order to borrow under the respective debt agreements, the Company and its subsidiaries must be in compliance with the applicable covenants and certain other conditions. In the event the Company or its subsidiaries do not comply with the applicable covenants and other conditions, alternative sources of funding may need to be pursued. As of September 30, 2025, the Company and its subsidiaries were in compliance with all covenants and conditions, except as otherwise noted below.
Long-term debt
Intermountain On July 15, 2025, Intermountain entered into a NPA to issue a total of $50.0 million of senior notes, with a maturity date of July 15, 2055, at an interest rate of 6.39 percent. On July 15, 2025, Intermountain issued $25.0 million in senior notes under the NPA with the remaining $25.0 million expected to be issued on November 14, 2025. This NPA is one of three distinct Intermountain NPAs that contain certain customary covenants, including a minimum interest coverage ratio. Intermountain was not in compliance with this minimum interest coverage ratio for the period ended September 30, 2025, which constituted an event of default under the terms of the Intermountain NPAs. In addition, the event of default under the terms of the Intermountain NPAs constituted a cross-default under the terms of certain NPAs of MDU Energy Capital and revolving credit agreements held by the Company and Intermountain. Subsequent to September 30, 2025, Intermountain and MDU Energy Capital obtained waivers for this non-compliance from the holders of a majority of their respective outstanding notes, and Intermountain and the Company obtained waivers from the lenders of the revolving credit agreements, which collectively cured the impact of any events of default. The Company expects to be in compliance with the minimum interest coverage ratio under the Intermountain NPAs by December 31, 2025.
Long-term Debt Outstanding Long-term debt outstanding was as follows:

| Weighted Average Interest Rate at September 30, 2025 | September 30, 2025 | September 30, 2024 | December 31, 2024
|  | (In thousands)
Senior Notes due on dates ranging from October 30, 2025 to June 15, 2062 | 4.60 | % | $ | 1,947,000 |  | $ | 1,947,000 |  | $ | 1,947,000 |
Credit agreements due on dates ranging from May 31, 2028 to June 20, 2029 | 6.06 | % | 183,400 |  | 163,500 |  | 169,700 |
Commercial paper supported by revolving credit agreement | 4.40 | % | 132,700 |  | 57,800 |  | 81,400 |
Term Loan Agreements due on dates ranging from September 3, 2032 to April 1, 2039 | 4.44 | % | 60,900 |  | 123,600 |  | 65,600 |
Medium-Term Notes due on dates ranging from September 15, 2027 to March 16, 2029 | 7.32 | % | 35,000 |  | 35,000 |  | 35,000 |
Other notes due on November 30, 2038 | 6.00 | % | 333 |  | 350 |  | 346 |
Less unamortized debt issuance costs |  | 6,148 |  | 6,953 |  | 6,436 |
Total long-term debt |  | 2,353,185 |  | 2,320,297 |  | 2,292,610 |
Less current maturities |  | 164,700 |  | 86,777 |  | 161,700 |
Net long-term debt |  | $ | 2,188,485 |  | $ | 2,233,520 |  | $ | 2,130,910 |

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Index
Note 14 - Cash flow information
Cash expenditures for interest and income taxes were as follows:

| Nine Months Ended
| September 30,
| 2025 | 2024 |
| (In thousands)
Interest, net* | $ | 68,267 |  | $ | 74,677 |
Income taxes paid, net | $ | 27,491 |  | $ | 14,385 |

*AFUDC - borrowed was $5.4 million and $8.4 million for the nine months ended September 30, 2025 and 2024, respectively.

Noncash investing and financing transactions were as follows:

| September 30, 2025 | September 30, 2024 | December 31, 2024
| (In thousands)
Right-of-use assets obtained in exchange for new operating lease liabilities | $ | 1,344 |  | $ | 1,104 |  | $ | 1,787 |
Property, plant and equipment additions in accounts payable | $ | 53,653 |  | $ | 49,393 |  | $ | 36,820 |

Note 15 - Business segment data
The Company's reportable segments are those that are based on the Company's method of internal reporting, which generally segregates the strategic business units due to differences in products, services and regulation. The internal reporting of these operating segments is defined based on the reporting and review process used by the Company's CODM, the chief executive officer. The Company's operations are located within the United States.
The Company's CODM regularly reviews discrete financial information of each reportable segment and uses net income to assess the performance of each reportable segment. The CODM uses this information to assess performance and make decisions about resources to be allocated to each reportable segment, including capital and personnel. The information provided to the CODM is prepared at the reportable segment level in quarterly financial packages and on a more summarized basis monthly. Budget and forecast information is also provided to the CODM at the reportable segment level.
The electric segment generates, transmits and distributes electricity in Montana, North Dakota, South Dakota and Wyoming. The natural gas distribution segment distributes natural gas in those states, as well as in Idaho, Minnesota, Oregon and Washington. These operations also supply related value-added services.
The pipeline segment provides natural gas transportation and underground storage services through a FERC regulated pipeline system primarily in the Rocky Mountain and northern Great Plains regions of the United States. This segment also provides non-regulated energy-related services, including cathodic protection.
The Other category includes the activities of Centennial Capital, which, through its subsidiary InterSource Insurance Company, insures various types of risks as a captive insurer for certain of the Company's subsidiaries. The function of the captive insurer is to fund the self-insured layers of the insured Company's general liability, automobile liability and other coverages. In addition, the Other category includes certain assets, liabilities and tax adjustments of the holding company primarily associated with corporate functions. Also included are certain general and administrative costs (reflected in operation and maintenance expense) and interest expense, which were previously allocated to Everus, Fidelity and the refining business which do not meet the criteria for income (loss) from discontinued operations.
Discontinued operations includes Everus' operations and certain associated separation costs. Discontinued operations also includes the supporting activities of Fidelity other than certain general and administrative costs and interest expense as described above.
24

Index
The information below follows the same accounting policies as described in Note 2 of the Notes to Consolidated Financial Statements in the 2024 Annual Report. Information on the Company's segments was as follows:

Three Months Ended September 30, 2025 | Electric |  | Natural gas distribution |  | Pipeline |  | Other |  | Consolidated
| (In thousands)
Operating revenues: |  |  |  |  |  |  |  |  |
External operating revenues | $ | 117,662 |  |  | $ | 144,215 |  |  | $ | 53,159 |  |  | $ | — |  |  | $ | 315,036 |
Intersegment operating revenues | 138 |  |  | 92 |  |  | 4,269 |  |  | 182 |  |  | 4,681 |
Purchased natural gas sold: |  |  |  |  |  |  |  |  |
External purchased natural gas sold | — |  |  | 58,514 |  |  | — |  |  | — |  |  | 58,514 |
Intersegment purchased natural gas sold | — |  |  | 4,226 |  |  | — |  |  | — |  |  | 4,226 |
Electric fuel and purchased power | 41,098 |  |  | — |  |  | — |  |  | — |  |  | 41,098 |
Operation and maintenance: |  |  |  |  |  |  |  |  |
External operation and maintenance | 25,957 |  |  | 56,531 |  |  | 21,016 |  |  | (1,742) |  |  | 101,762 |
Intersegment operation and maintenance | 138 |  |  | 92 |  |  | 43 |  |  | 182 |  |  | 455 |
Depreciation and amortization | 17,479 |  |  | 26,558 |  |  | 8,009 |  |  | — |  |  | 52,046 |
Taxes, other than income | 4,713 |  |  | 13,375 |  |  | 3,688 |  |  | — |  |  | 21,776 |
Other income: |  |  |  |  |  |  |  |  |
External other income | 2,027 |  |  | 3,850 |  |  | 880 |  |  | 541 |  |  | 7,298 |
Intersegment other income | — |  |  | — |  |  | 122 |  |  | 1,565 |  |  | 1,687 |
Interest expense: |  |  |  |  |  |  |  |  |
External interest expense | 7,639 |  |  | 14,686 |  |  | 2,447 |  |  | 1,645 |  |  | 26,417 |
Intersegment interest expense | — |  |  | — |  |  | 1,687 |  |  | — |  |  | 1,687 |
Income tax expense (benefit) | 1,339 |  |  | (7,612) |  |  | 4,782 |  |  | 3,862 |  |  | 2,371 |
Income (loss) from continuing operations | 21,464 |  |  | (18,213) |  |  | 16,758 |  |  | (1,659) |  |  | 18,350 |
Discontinued operations, net of tax | — |  |  | — |  |  | — |  |  | (39) |  |  | (39) |
Net income (loss) | $ | 21,464 |  |  | $ | (18,213) |  |  | $ | 16,758 |  |  | $ | (1,698) |  |  | $ | 18,311 |

25

Index

Three Months Ended September 30, 2024 | Electric |  | Natural gas distribution |  | Pipeline |  | Other |  | Consolidated
| (In thousands)
Operating revenues: |  |  |  |  |  |  |  |  |
External operating revenues | $ | 108,468 |  |  | $ | 133,590 |  |  | $ | 47,635 |  |  | $ | 1 |  |  | $ | 289,694 |
Intersegment operating revenues | 12 |  |  | 31 |  |  | 3,924 |  |  | 21 |  |  | 3,988 |
Purchased natural gas sold: |  |  |  |  |  |  |  |  |
External purchased natural gas sold | — |  |  | 53,377 |  |  | — |  |  | — |  |  | 53,377 |
Intersegment purchased natural gas sold | — |  |  | 3,888 |  |  | — |  |  | — |  |  | 3,888 |
Electric fuel and purchased power | 32,576 |  |  | — |  |  | — |  |  | — |  |  | 32,576 |
Operation and maintenance: |  |  |  |  |  |  |  |  |
External operation and maintenance | 23,359 |  |  | 54,785 |  |  | 18,969 |  |  | 4,098 |  |  | 101,211 |
Intersegment operation and maintenance | 12 |  |  | 31 |  |  | 36 |  |  | 21 |  |  | 100 |
Depreciation and amortization | 16,848 |  |  | 25,055 |  |  | 7,369 |  |  | 563 |  |  | 49,835 |
Taxes, other than income | 3,606 |  |  | 11,180 |  |  | 3,006 |  |  | 57 |  |  | 17,849 |
Other income: |  |  |  |  |  |  |  |  |
External other income | 1,403 |  |  | 5,985 |  |  | 1,117 |  |  | 465 |  |  | 8,970 |
Intersegment other income | — |  |  | — |  |  | 237 |  |  | 3,794 |  |  | 4,031 |
Interest expense: |  |  |  |  |  |  |  |  |
External interest expense | 7,646 |  |  | 15,901 |  |  | 2,564 |  |  | 1,226 |  |  | 27,337 |
Intersegment interest expense | — |  |  | — |  |  | 1,097 |  |  | 2,934 |  |  | 4,031 |
Income tax expense (benefit) | 1,544 |  |  | (7,130) |  |  | 4,688 |  |  | 1,774 |  |  | 876 |
Income (loss) from continuing operations | 24,292 |  |  | (17,481) |  |  | 15,184 |  |  | (6,392) |  |  | 15,603 |
Discontinued operations, net of tax | — |  |  | — |  |  | — |  |  | 49,012 |  |  | 49,012 |
Net income (loss) | $ | 24,292 |  |  | $ | (17,481) |  |  | $ | 15,184 |  |  | $ | 42,620 |  |  | $ | 64,615 |

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Index

Nine Months Ended September 30, 2025 | Electric |  | Natural gas distribution |  | Pipeline |  | Other |  | Consolidated
| (In thousands)
Operating revenues: |  |  |  |  |  |  |  |  |
External operating revenues | $ | 327,808 |  |  | $ | 890,257 |  |  | $ | 122,990 |  |  | $ | — |  |  | $ | 1,341,055 |
Intersegment operating revenues | 457 |  |  | 278 |  |  | 47,401 |  |  | 540 |  |  | 48,676 |
Purchased natural gas sold: |  |  |  |  |  |  |  |  |
External purchased natural gas sold | — |  |  | 471,728 |  |  | — |  |  | — |  |  | 471,728 |
Intersegment purchased natural gas sold | — |  |  | 47,300 |  |  | — |  |  | — |  |  | 47,300 |
Electric fuel and purchased power | 119,737 |  |  | — |  |  | — |  |  | — |  |  | 119,737 |
Operation and maintenance: |  |  |  |  |  |  |  |  |
External operation and maintenance | 84,186 |  |  | 180,471 |  |  | 62,608 |  |  | (1,569) |  |  | 325,696 |
Intersegment operation and maintenance | 457 |  |  | 278 |  |  | 101 |  |  | 540 |  |  | 1,376 |
Depreciation and amortization | 52,055 |  |  | 79,151 |  |  | 23,954 |  |  | — |  |  | 155,160 |
Taxes, other than income | 14,176 |  |  | 60,938 |  |  | 10,585 |  |  | — |  |  | 85,699 |
Other income: |  |  |  |  |  |  |  |  |
External other income | 5,745 |  |  | 12,246 |  |  | 2,804 |  |  | 1,445 |  |  | 22,240 |
Intersegment other income | — |  |  | — |  |  | 334 |  |  | 3,613 |  |  | 3,947 |
Interest expense: |  |  |  |  |  |  |  |  |
External interest expense | 23,140 |  |  | 43,307 |  |  | 8,703 |  |  | 3,534 |  |  | 78,684 |
Intersegment interest expense | — |  |  | — |  |  | 3,947 |  |  | — |  |  | 3,947 |
Income tax expense (benefit) | (6,646) |  |  | 519 |  |  | 14,246 |  |  | 3,478 |  |  | 11,597 |
Income from continuing operations | 46,905 |  |  | 19,089 |  |  | 49,385 |  |  | (385) |  |  | 114,994 |
Discontinued operations, net of tax | — |  |  | — |  |  | — |  |  | (938) |  |  | (938) |
Net income | $ | 46,905 |  |  | $ | 19,089 |  |  | $ | 49,385 |  |  | $ | (1,323) |  |  | $ | 114,056 |

27

Index

Nine Months Ended September 30, 2024 | Electric |  | Natural gas distribution |  | Pipeline |  | Other |  | Consolidated
| (In thousands)
Operating revenues: |  |  |  |  |  |  |  |  |
External operating revenues | $ | 315,385 |  |  | $ | 794,519 |  |  | $ | 112,518 |  |  | $ | 18 |  |  | $ | 1,222,440 |
Intersegment operating revenues | 71 |  |  | 108 |  |  | 43,249 |  |  | 64 |  |  | 43,492 |
Purchased natural gas sold: |  |  |  |  |  |  |  |  |
External purchased natural gas sold | — |  |  | 406,569 |  |  | — |  |  | — |  |  | 406,569 |
Intersegment purchased natural gas sold | — |  |  | 42,958 |  |  | — |  |  | — |  |  | 42,958 |
Electric fuel and purchased power | 108,991 |  |  | — |  |  | — |  |  | — |  |  | 108,991 |
Operation and maintenance: |  |  |  |  |  |  |  |  |
External operation and maintenance | 69,989 |  |  | 169,034 |  |  | 56,461 |  |  | 13,296 |  |  | 308,780 |
Intersegment operation and maintenance | 71 |  |  | 108 |  |  | 291 |  |  | 64 |  |  | 534 |
Depreciation and amortization | 49,685 |  |  | 76,081 |  |  | 21,806 |  |  | 1,720 |  |  | 149,292 |
Taxes, other than income | 13,222 |  |  | 55,130 |  |  | 9,108 |  |  | 271 |  |  | 77,731 |
Other income: |  |  |  |  |  |  |  |  |
External other income | 5,449 |  |  | 19,506 |  |  | 4,616 |  |  | 1,671 |  |  | 31,242 |
Intersegment other income | — |  |  | — |  |  | 692 |  |  | 12,253 |  |  | 12,945 |
Interest expense: |  |  |  |  |  |  |  |  |
External interest expense | 22,367 |  |  | 46,925 |  |  | 7,466 |  |  | 3,591 |  |  | 80,349 |
Intersegment interest expense | — |  |  | — |  |  | 3,949 |  |  | 8,996 |  |  | 12,945 |
Income tax expense (benefit) | (1,109) |  |  | (253) |  |  | 14,493 |  |  | (1,741) |  |  | 11,390 |
Income (loss) from continuing operations | 57,689 |  |  | 17,581 |  |  | 47,501 |  |  | (12,191) |  |  | 110,580 |
Discontinued operations, net of tax | — |  |  | — |  |  | — |  |  | 115,370 |  |  | 115,370 |
Net income | $ | 57,689 |  |  | $ | 17,581 |  |  | $ | 47,501 |  |  | $ | 103,179 |  |  | $ | 225,950 |

A reconciliation of reportable segment operating revenues to consolidated operating revenues is as follows:

| Three Months Ended | Nine Months Ended
| September 30, | September 30,
| 2025 |  | 2024 |  | 2025 |  | 2024 |
| (In thousands)
Operating revenues reconciliation: |  |  |  |
Total reportable segment operating revenues | $ | 319,535 |  | $ | 293,660 |  | $ | 1,389,191 |  | $ | 1,265,850 |
Other revenue | 182 |  | 22 |  | 540 |  | 82 |
Elimination of intersegment operating revenues | (4,681) |  | (3,988) |  | (48,676) |  | (43,492) |
Total consolidated operating revenues | $ | 315,036 |  | $ | 289,694 |  | $ | 1,341,055 |  | $ | 1,222,440 |

Note 16 - Employee benefit plans
Pension and other postretirement plans
The Company has noncontributory qualified defined benefit pension plans and other postretirement benefit plans for certain eligible employees.
Components of net periodic benefit cost for the Company's pension benefit plans were as follows:

| Three Months Ended | Nine Months Ended
| September 30, | September 30,
| 2025 | 2024 | 2025 | 2024
| (In thousands)
Components of net periodic benefit cost: |  |  |  |
Interest cost | $ | 3,303 |  | $ | 3,200 |  | $ | 9,909 |  | $ | 9,600 |
Expected return on assets | (3,645) |  | (4,028) |  | (10,935) |  | (12,084) |
Amortization of net actuarial loss | 1,193 |  | 1,037 |  | 3,580 |  | 3,111 |
Net periodic benefit cost | $ | 851 |  | $ | 209 |  | $ | 2,554 |  | $ | 627 |

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Index
Components of net periodic benefit credit for the Company's other postretirement benefit plans were as follows:

| Three Months Ended | Nine Months Ended
| September 30, | September 30,
| 2025 | 2024 | 2025 | 2024
| (In thousands)
Components of net periodic benefit credit: |  |  |  |
Service cost | $ | 99 |  | $ | 126 |  | $ | 297 |  | $ | 378 |
Interest cost | 462 |  | 459 |  | 1,386 |  | 1,377 |
Expected return on assets | (1,292) |  | (1,329) |  | (3,876) |  | (3,987) |
Amortization of prior service credit | (290) |  | (330) |  | (869) |  | (990) |
Amortization of net actuarial gain | (80) |  | (72) |  | (240) |  | (216) |
Net periodic benefit credit, including amount capitalized | (1,101) |  | (1,146) |  | (3,302) |  | (3,438) |
Less amount capitalized | 18 |  | 25 |  | 54 |  | 72 |
Net periodic benefit credit | $ | (1,119) |  | $ | (1,171) |  | $ | (3,356) |  | $ | (3,510) |

The components of net periodic benefit cost (credit), other than the service cost component, are included in Other income on the Consolidated Statements of Income. The service cost component is included in Operation and maintenance expense on the Consolidated Statements of Income.
Nonqualified defined benefit plans
In addition to the qualified defined benefit pension plans reflected in the table at the beginning of this note, the Company also has unfunded, nonqualified defined benefit plans for executive officers and certain key management employees. The Company's net periodic benefit cost for these plans was $716,000 and $733,000 for the three months ended September 30, 2025 and 2024, respectively, and $2.1 million and $2.2 million for the nine months ended September 30, 2025 and 2024, respectively. The components of net periodic benefit cost for these plans are included in Other income on the Consolidated Statements of Income.
Note 17 - Regulatory matters
The Company regularly reviews the need for electric and natural gas rate changes in each of the jurisdictions in which service is provided. The Company files for rate adjustments to seek recovery of operating costs and capital investments, as well as reasonable returns as allowed by regulators. Certain regulatory proceedings and cases may also contain recurring mechanisms that can have an annual true-up. Examples of these recurring mechanisms include: infrastructure riders, transmission trackers, renewable resource cost adjustment riders, as well as weather normalization and decoupling mechanisms. The following paragraphs summarize the Company's significant open regulatory proceedings and cases by jurisdiction including updates to those reported in the 2024 Annual Report and should be read in conjunction with previous filings. The Company is unable to predict the ultimate outcome of these matters, the timing of final decisions of the various regulators and courts, or the effect on the Company's results of operations, financial position or cash flows.
IPUC
On May 30, 2025, Intermountain filed a request with the IPUC for a natural gas general rate increase of approximately $26.5 million annually or 8.6 percent above current rates. The requested increase is primarily to recover increased operating expenses and costs associated with plant additions, as well as revenues necessary to produce a fair rate of return to enable continued safe and reliable service. On October 20, 2025, an all-party settlement agreement was filed reflecting an annual revenue increase of $13.0 million or 4.2 percent. The IPUC has a hearing scheduled November 18 and 19, 2025, with rates expected to be effective January 1, 2026. The reduction from the original filing is largely related to a lower return on equity, a monthly average rate base methodology versus end of period, and reduced incentives.
NDPSC
On July 15, 2025, Montana-Dakota filed an annual update to its transmission cost adjustment rider with the NDPSC requesting to recover revenues of approximately $6.3 million, which includes a true-up of the prior period adjustment, resulting in an increase of approximately $7.2 million over current rates. Included in this filing is capital investment in transmission projects and the associated revenue of approximately $8.6 million. On October 23, 2025, the NDPSC approved the transmission cost adjustment with rates effective November 1, 2025.
Montana-Dakota has a renewable resource cost adjustment rate tariff that allows for annual adjustments for recent projected capital costs and related expenses for projects determined to be recoverable under the tariff. On October 31, 2025, Montana-Dakota filed an annual update to its renewable resource cost adjustment, including Badger Wind, requesting to recover a revenue requirement of approximately $43.6 million annually. The update reflects an increase of approximately $25.3 million annually from the revenues currently included in rates.
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Index
MTPSC
On July 15, 2024, Montana-Dakota filed a request with the MTPSC for a natural gas general rate increase of approximately $9.4 million annually or 11.1 percent above current rates. The requested increase is primarily to recover investments in system upgrades and pipeline replacement projects enhancing the reliability, safety and integrity of the natural gas system, as well as increased costs to operate and maintain that system. On October 15, 2024, the MTPSC denied Montana-Dakota's request for an interim rate increase of approximately $8.0 million annually or 10.2 percent above current rates. On October 25, 2024, Montana-Dakota filed a motion for reconsideration of the interim rate increase. On January 14, 2025, the MTPSC approved an interim increase of approximately $7.7 million with interim rates effective on and after February 1, 2025. On April 3, 2025, an all-party settlement agreement was filed reflecting an annual revenue increase of $7.3 million or 8.6 percent overall. On October 7, 2025, the MTPSC approved the settlement with rates effective November 1, 2025.
On September 30, 2025, Montana-Dakota filed a request with the MTPSC for an electric general rate increase of approximately $14.1 million annually or 20.2 percent above current rates. The requested increase is primarily to recover investments, including Badger Wind, made since the last regulatory procedure, the corresponding depreciation on those investments and increased operation and maintenance expenses. The filing includes a request for a Systems Management Cost Adjustment mechanism for cost recovery of transmission and wildfire related costs. This matter is pending before the MTPSC.
SDPUC
Montana-Dakota has an infrastructure rider that allows annual adjustments for recent projected capital costs and related expense for projects determined to be recoverable under the tariff. On October 31, Montana-Dakota filed an annual update to its infrastructure rider, including Badger Wind, requesting to recover a revenue requirement of approximately $1.5 million annually. The update reflects an increase of $1.1 million annually from the revenues currently included in rates.
WYPSC
On June 30, 2025, Montana-Dakota filed a request with the WYPSC for an electric general rate increase of approximately $7.5 million annually or 24.4 percent above current rates. The filing includes a request for a Reliability and Safety Infrastructure Rider. The requested increase is primarily to recover increases in operation and maintenance expenses, investments made since the last rate case, and the corresponding depreciation on those infrastructure investments. This matter is pending before the WYPSC.
On August 15, 2025, Montana-Dakota filed for approval with the WYPSC a gas System Safety and Integrity Rider. The System Safety Integrity Rider would allow Montana-Dakota to recover costs and expenses associated with a pipeline replacement program.
Note 18 - Commitments and contingencies
The Company is party to claims and lawsuits arising out of its business and that of its consolidated subsidiaries, which may include, but are not limited to, matters involving property damage, personal injury, and environmental, contractual, statutory and regulatory obligations. The Company accrues a liability for those contingencies when the incurrence of a loss is probable and the amount can be reasonably estimated. If a range of amounts can be reasonably estimated and no amount within the range is a better estimate than any other amount, then the minimum of the range is accrued. The Company does not accrue liabilities when the likelihood that the liability has been incurred is probable but the amount cannot be reasonably estimated or when the liability is believed to be only reasonably possible or remote. For contingencies where an unfavorable outcome is probable or reasonably possible and which are material, the Company discloses the nature of the contingency and, in some circumstances, an estimate of the possible loss. Accruals are based on the best information available, but in certain situations management is unable to estimate an amount or range of a reasonably possible loss including, but not limited to when: (1) the damages are unsubstantiated or indeterminate, (2) the proceedings are in the early stages, (3) numerous parties are involved, or (4) the matter involves novel or unsettled legal theories.
At September 30, 2025 and 2024, and December 31, 2024, the Company accrued liabilities, which have not been discounted, of $25.1 million, $22.0 million and $24.1 million, respectively. The Company also recorded corresponding receivables of $1.9 million at September 30, 2025. The receivable amounts were not material at September 30, 2024 and December 31, 2024. The Company recorded regulatory assets of $22.1 million, $20.9 million and $22.9 million, at September 30, 2025 and 2024, and December 31, 2024, respectively, related to the accrued liabilities. The accruals are for contingencies resulting from litigation, regulatory and environmental matters. This includes amounts that have been accrued for matters discussed in Environmental matters within this note. The Company will continue to monitor each matter and adjust accruals as might be warranted based on new information and further developments. Management believes that the outcomes with respect to probable and reasonably possible losses in excess of the amounts accrued, net of recoveries, while uncertain, either cannot be estimated or will not have a material effect upon the Company's financial position, results of operations or cash flows. Unless otherwise required by GAAP, legal costs are expensed as they are incurred.
Environmental matters
The Company is a party to claims for the cleanup of environmental contamination at certain manufactured gas plant sites. There were no material changes to the Company's environmental matters that were previously reported in the 2024 Annual Report.
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Index
Purchase Commitments
The Company has entered in various commitments largely consisting of contracts for natural gas and coal supply; purchased power; natural gas transportation and storage; information technology; and environmental compliance instruments. Certain of these contracts are subject to variability in volume and price. The purchase commitments at September 30, 2025, under these contracts for the twelve month periods ending September 30, were:

| 2026 | 2027 | 2028 | 2029 | 2030 | Thereafter
| (In thousands)
Purchase Commitments | $ | 939,500 |  | $ | 280,400 |  | $ | 174,200 |  | $ | 128,800 |  | $ | 113,700 |  | $ | 627,000 |

The Company's purchase commitments decreased from those reported in the 2024 Annual Report due to an anticipated decrease in electric supply contracts as a result of the Badger Wind, LLC purchase and sale agreement at the Company's electric segment.
In February 2025, Montana-Dakota entered into a definitive purchase and sale agreement with Badger Wind, LLC, a subsidiary of Orsted Onshore North America, LLC. Pursuant to the terms of the agreement, Montana-Dakota will purchase a 49 percent undivided ownership interest in a wind project being constructed and located in North Dakota that is anticipated to have a net generating capacity of approximately 250 MW for a purchase price of $294.0 million, which would represent 122.5 MW of wind generation to be owned by Montana-Dakota. In September 2025, the NDPSC granted an advanced determination of prudence and certificate of public convenience and necessity. The project is expected to be completed near the end of 2025. This transaction would reduce Montana-Dakota's purchase requirements under the existing power purchase agreement with Badger Wind, LLC, dated November 4, 2024.
Guarantees
The Company and certain subsidiaries have outstanding letters of credit to third parties related to insurance policies and other agreements, some of which are guaranteed by other subsidiaries of the Company. At September 30, 2025, the fixed maximum amounts guaranteed under these letters of credit aggregated $3.2 million, all of which have scheduled expiration of the maximum amounts in 2025. There were no amounts outstanding under the previously mentioned letters of credit at September 30, 2025. In the event of default under these letter of credit obligations, the Company or subsidiary guaranteeing the letter of credit would be obligated for reimbursement of payments made under the letter of credit.
In the normal course of business, the Company and its subsidiaries have surety bonds. In the event the Company or its subsidiaries do not fulfill a bonded obligation, the Company or its subsidiaries would be responsible to the surety bond company for completion of the bonded contract or obligation. At September 30, 2025, approximately $13.0 million of surety bonds were outstanding, which were not reflected on the Consolidated Balance Sheet.
Leases
The Company's leases primarily include operating leases for equipment, buildings, easements and vehicles. The Company leases certain equipment to third parties through its utility business, which are considered short-term operating leases with terms of less than 12 months. Lease revenue was not material for the three and nine months ended September 30, 2025 or 2024. At September 30, 2025, the Company had no lease receivables.
Variable interest entities
The Company evaluates its arrangements and contracts with other entities to determine if they are VIEs and if so, if the Company is the primary beneficiary.
Fuel Contract Coyote Station entered into a coal supply agreement with Coyote Creek that provides for the purchase of coal necessary to supply the coal requirements of the Coyote Station for the period May 2016 through December 2040. Coal purchased under the coal supply agreement is reflected in Inventories on the Consolidated Balance Sheets and is recovered from customers as a component of electric fuel and purchased power.
The coal supply agreement creates a variable interest in Coyote Creek due to the transfer of all operating and economic risk to the Coyote Station owners, as the agreement is structured so that the price of the coal will cover all costs of operations, as well as future reclamation costs. The Coyote Station owners are also providing a guarantee of the value of the assets of Coyote Creek as they would be required to buy the assets at book value should they terminate the contract prior to the end of the contract term and are providing a guarantee of the value of the equity of Coyote Creek in that they are required to buy the entity at the end of the contract term at equity value. Although the Company has determined that Coyote Creek is a VIE, the Company has concluded that it is not the primary beneficiary of Coyote Creek because the authority to direct the activities of the entity is shared by the four unrelated owners of the Coyote Station, with no primary beneficiary existing. As a result, Coyote Creek is not required to be consolidated in the Company's financial statements.
At September 30, 2025, the Company's exposure to loss as a result of the Company's involvement with the VIE, based on the Company's ownership percentage, was $24.1 million.
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Index
Note 19 - Subsequent events
On October 28, 2025, Montana-Dakota entered into a NPA to issue $250.0 million of senior notes, with maturity dates ranging from October 28, 2035 to February 2, 2056, at a weighted average interest rate of 5.96 percent. On October 28, 2025, Montana-Dakota issued $150.0 million in senior notes under the NPA with the remaining $100.0 million expected to be issued on February 2, 2026. The agreement contains customary covenants and provisions, including a covenant of Montana-Dakota not to permit, at any time, the ratio of debt to total capitalization to be greater than 65 percent. Other covenants include a minimum interest coverage ratio and restrictions on the sale of certain assets.
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Index
Item 2. Management's Discussion and Analysis of Financial Condition and Results of Operations
The Company generates, transmits and distributes electricity and provides natural gas distribution, transportation and storage services. Through a strategy focusing on its "CORE," the Company strives to deliver superior value and achieve industry-leading performance as a pure-play regulated energy delivery company, while pursuing organic growth opportunities. The Company's "CORE" strategy prioritizes customers and communities, operational excellence, returns focused initiatives and an employee driven culture.
Strategic Initiatives On October 31, 2024, the Company completed the separation of Everus, its former construction services business, resulting in Everus becoming an independent, publicly-traded company. The Company's board of directors approved the distribution of all the outstanding shares of Everus common stock to the Company's stockholders. Stockholders of the Company received one share of Everus common stock for every four shares of the Company's common stock held as of the close of business on October 21, 2024, the record date for the distribution. The separation of Everus was a tax-free spinoff transaction to the Company's stockholders for U.S. federal income tax purposes, except for cash received in lieu of fractional shares.
The Company incurred costs in connection with its strategic initiatives in 2024 and 2025, as noted in the Business Segment Financial and Operating Data section. The majority of the separation costs have already been incurred due to the separation of Everus in October 2024, as previously discussed.
Dividends Based on the Company becoming a pure-play regulated energy delivery business, the Company's board of directors established a long-term dividend payout ratio target of 60 percent to 70 percent of regulated energy delivery earnings. The Company has an 87-year history of uninterrupted dividend payments to stockholders and remains committed to paying a competitive dividend.
One Big Beautiful Bill Act On July 4, 2025, the reconciliation bill was enacted into law, extending key provisions of the 2017 Tax Cuts and Jobs Act while scaling back clean energy tax incentives of the IRA. Changes in tax laws may affect recorded deferred tax assets and deferred tax liabilities or the Company's effective tax rates in the future. The Company has evaluated new legislation, and it does not expect a material impact to the consolidated financial statements or ongoing tax rate as a result of this legislation.
Market Trends The Company continues to manage the inflationary pressures experienced throughout the United States, including the impact that inflation, higher interest rates, changes in tariffs, commodity price volatility and supply chain disruptions may have on its business and customers and proactively looks for ways to lessen the impact to its business. The Company has observed supply chain improvements in lead times for certain commodities. The Company has experienced impacts related to the changes in tariffs and continues to navigate the current environment and monitor the future for impacts that could occur. For more information specific to each of the Company's businesses, see the following discussion in each business segment's Outlook section. For more information on the possible impacts, see Part II, Item 1A. Risk Factors in this Form 10-Q and Part I, Item 1A. Risk Factors in the 2024 Annual Report.
Cautionary Note Regarding Forward-Looking Statements
This Quarterly Report on Form 10-Q contains forward-looking statements within the meaning of the federal securities laws. Other than statements of historical facts, all statements which address activities, events, or developments that the Company anticipates will or may occur in the future are based on underlying assumptions (many of which are based, in turn, upon further assumptions), including, but not limited to, statements identified by the words "anticipates," "estimates," "expects," "intends," "plans," and "predicts," in each case related to such things as growth estimates, stockholder value creation, the Company's "CORE" strategy, capital expenditures, trends, objectives, goals, dividend payout ratio targets, strategies and other such matters, are forward-looking statements. These forward-looking statements are based on many assumptions and factors, which are detailed in the Company's filings with the SEC.
While made in good faith, these forward-looking statements are based largely on the Company's expectations and judgments and are subject to a number of risks and uncertainties, many of which are unforeseeable and beyond the Company's control. For additional discussion regarding risks and uncertainties that may affect forward-looking statements, see Part II, Item 1A. Risk Factors in this quarterly report, Part I, Item 1A. Risk Factors in the 2024 Annual Report and subsequent filings with the SEC. Any changes in such assumptions or factors could produce significantly different results. Undue reliance should not be placed on forward-looking statements, which speak only as of the date they are made. Except as required by applicable law, the Company undertakes no obligation to update the forward-looking statements, whether as a result of new information, future events, or otherwise.
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Consolidated Earnings Overview
The following table summarizes the contribution to the consolidated income by each of the Company's business segments.

| Three Months Ended |  | Nine Months Ended
| September 30, |  | September 30,
| 2025 |  | 2024 |  |  | 2025 |  | 2024 |
| (In millions, except per share amounts)
Electric | $ | 21.5 |  | $ | 24.3 |  |  | $ | 46.9 |  | $ | 57.7 |
Natural gas distribution | (18.2) |  | (17.5) |  |  | 19.1 |  | 17.6 |
Pipeline | 16.8 |  | 15.1 |  |  | 49.4 |  | 47.5 |
Other | (1.7) |  | (6.3) |  |  | (.4) |  | (12.2) |
Income from continuing operations | 18.4 |  | 15.6 |  |  | 115.0 |  | 110.6 |
Discontinued operations, net of tax | — |  | 49.0 |  |  | (.9) |  | 115.3 |
Net income | $ | 18.4 |  | $ | 64.6 |  |  | $ | 114.1 |  | $ | 225.9 |
Earnings per share - basic: |  |  |  |  |
Income from continuing operations | $ | .09 |  | $ | .08 |  |  | $ | .56 |  | $ | .54 |
Discontinued operations, net of tax | — |  | .24 |  |  | — |  | .57 |
Earnings per share - basic | $ | .09 |  | $ | .32 |  |  | $ | .56 |  | $ | 1.11 |
Earnings per share - diluted: |  |  |  |  |
Income from continuing operations | $ | .09 |  | $ | .08 |  |  | $ | .56 |  | $ | .54 |
Discontinued operations, net of tax | — |  | .24 |  |  | — |  | .57 |
Earnings per share - diluted | $ | .09 |  | $ | .32 |  |  | $ | .56 |  | $ | 1.11 |

On October 31, 2024, the Company completed the separation of Everus, its former construction services business, into a new independent publicly-traded company. As a result of the separation, the historical results of operations for Everus are shown in discontinued operations, net of tax, except for allocated general corporate overhead costs of the Company, which did not meet the criteria for discontinued operations and are reflected in Other. Also included in discontinued operations are certain strategic initiative costs associated with the separation of Everus.
Three Months Ended September 30, 2025, Compared to Three Months Ended September 30, 2024 The Company's consolidated earnings decreased $46.2 million. The decrease in earnings is primarily due to the absence of income from discontinued operations in 2025. Other drivers of the earnings decrease include:
•The electric business earnings decrease was largely the result of higher operation and maintenance expense, primarily due to increased payroll-related costs and higher contract services related to electric generation station outage-related costs. Higher depreciation expense, primarily associated with capital projects placed in service, further drove the decrease. The decrease in net income was partially offset by higher retail sales revenue.
•The natural gas distribution business reported an increased seasonal loss, largely the result of higher operation and maintenance expense, primarily due to higher payroll-related costs and decreased interest income associated with lower purchased gas costs. Higher depreciation expense, primarily associated with capital projects placed in service, further drove the loss. The seasonal loss was partially offset by higher retail sales revenue due to rate relief in Washington, Montana, and Wyoming, as well as lower interest expense.
•The earnings increase at the pipeline business was driven by higher transportation revenue due to growth projects placed in service in late 2024 and customer demand for short-term natural gas transportation contracts. The increase was offset in part by higher operation and maintenance expense, primarily attributable to payroll-related costs. The business also incurred higher property tax accruals in Montana and higher depreciation expense due to growth projects placed in service.
•Other experienced lower operation and maintenance expense, primarily a result of corporate overhead costs classified as continuing operations allocated to Everus in 2024, which are not included in Other in 2025, and lower insurance claims experience at the captive insurer. Other was negatively impacted by higher income tax adjustments related to the Company's annualized estimated tax rate.
•As previously discussed, the Company was adversely impacted by the absence of income from discontinued operations in 2025.
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Nine Months Ended September 30, 2025, Compared to Nine Months Ended September 30, 2024 The Company's consolidated earnings decreased $111.8 million. The decrease in earnings is primarily due to the absence of income from discontinued operations in 2025.
•The electric business earnings decrease was largely the result of higher operation and maintenance expense, primarily due to higher payroll-related costs, higher contract services related to electric generation station outage-related costs, increased software expenses, which includes certain costs associated with TSA services provided, and higher insurance expense. The decrease in net income was partially offset by higher retail sales volumes, partly from a data center near Ellendale, North Dakota.
•The natural gas distribution earnings improvement was largely the result of higher rate relief in Washington, Montana, South Dakota and Wyoming and increased volumes due to colder weather in certain jurisdictions. These increases were partially offset by higher operation and maintenance expense, primarily due to increased payroll-related costs, higher software expenses, which includes certain costs associated with TSA services provided, and higher insurance expense. Lower interest income also negatively impacted earnings.
•The earnings increase at the pipeline business was driven by growth projects placed in service throughout 2024 and customer demand for short-term natural gas transportation contracts. Higher storage-related revenue further drove the increase. The increase was partially offset by higher operation and maintenance expense, primarily attributable to payroll-related costs. The absence of $1.5 million, net of tax proceeds received in 2024 from a customer settlement further offset the increase. The business also incurred higher depreciation expense due to growth projects placed in service, as previously discussed, and higher property tax accruals in Montana.
•Other experienced lower operation and maintenance expense, primarily a result of corporate overhead costs classified as continuing operations allocated to Everus in 2024, which are not included in Other in 2025, and lower insurance claims experience at the captive insurer.
•As previously discussed, the Company was adversely impacted by the absence of income from discontinued operations in 2025.
A discussion of key financial data from the Company's business segments follows.
Business Segment Financial and Operating Data
The following sections include key financial and operating data for each of the Company's business segments. Also included are highlights on key growth strategies, projections and certain assumptions for the Company and its subsidiaries and other matters of the Company's business segments.
The Company's CODM, the chief executive officer of MDU Resources Group, Inc., regularly reviews discrete financial information of each reportable segment and uses net income to assess performance of each reportable segment. The CODM uses this information to assess performance and make decisions about resources to be allocated to each reportable segment, including capital and personnel. The information provided to the CODM is prepared at the reportable segment level in quarterly financial packages and on a more summarized basis monthly. Budget and forecast information is also provided to the CODM at the reportable segment level.
For information pertinent to various commitments and contingencies, see the Notes to Consolidated Financial Statements. For a summary of the Company's business segments, see Note 15 of the Notes to Consolidated Financial Statements.
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Electric and Natural Gas Distribution
Strategy and challenges The electric and natural gas distribution segments provide electric and natural gas distribution services to customers, as discussed in Note 15. Both segments strive to be top performing utilities and provide safe, reliable, competitively priced and environmentally responsible energy services to customers. The segments are focused on cultivating organic growth while managing operating costs and monitoring opportunities for these segments to retain, grow and expand their customer base through extensions of existing operations, including building and upgrading electric generation, transmission and distribution, and natural gas systems. The continued efforts to create operational improvements and efficiencies across both segments promotes the Company's business integration strategy. The primary factors that impact the results of these segments are the ability to earn authorized rates of return; weather; climate change laws, regulations and initiatives; competitive factors in the energy industry; population growth; and economic conditions in the segments' service areas.
The electric and natural gas distribution segments are subject to extensive regulation in the jurisdictions where they conduct operations with respect to costs, timely recovery of investments and permitted returns on investment. The Company is focused on modernizing utility infrastructure to meet the varied energy needs of both its customers and communities while working to deliver safe, reliable, affordable and environmentally responsible energy. The segments continue to invest in facility upgrades to be in compliance with existing and known future regulations. To assist in the reduction of regulatory lag in obtaining revenue increases to align with increased investments, tracking mechanisms have been implemented in certain jurisdictions. The Company also seeks rate adjustments for operating costs and capital investments, as well as reasonable returns on investments not covered by tracking mechanisms. For more information on the Company's tracking mechanisms and recent rate cases, see Note 17 and the 2024 Annual Report.
These segments are also subject to extensive regulation related to certain operational and environmental compliance, cybersecurity, permit terms and system integrity. Both segments are faced with the ongoing need to actively evaluate cybersecurity processes and procedures related to its transmission and distribution systems for opportunities to further strengthen its cybersecurity protections. There have been cyber and physical attacks within the energy industry on infrastructure, such as substations, and the Company continues to evaluate the safeguards implemented to protect its electric and natural gas utility systems. Implementation of enhancements and additional requirements to protect the Company's infrastructure is ongoing.
To date, many states have enacted and others are considering, mandatory clean energy standards requiring utilities to meet certain thresholds of renewable and/or carbon-free energy supply. Over the long-term, the Company expects overall electric demand to be positively impacted by increased electrification trends as a means to address economy-wide carbon emission concerns, large data center growth and changing customer conservation patterns. Recently, MISO and NERC announced concerns with the reliability of the electric grid due to rapid expansion of renewables and retirement of baseload resources such as coal and the uncertainty of adequate energy production during certain periods of time, while load growth has increased faster than expected primarily due to growth in the data center industry. Montana-Dakota filed its 2024 IRP with the NDPSC in July 2024. With MISO's filed changes in resources adequacy at FERC and the adoption of direct loss of load accreditation for generation resources around riskiest hours on the system versus peak load hours, Montana-Dakota is seeing the need to add additional capacity resources to its system in 2028 versus 2034 as identified in its previous IRP. The Company signed a power purchase and ownership purchase agreement with Badger Wind, LLC for 150 MW of output capacity from the 250 MW Badger Wind Project which will reduce the Company's capacity and energy purchase requirements as identified in the 2024 IRP. Montana-Dakota will continue to monitor the progress of these changes, including the impacts associated with the implementation of MISO's direct loss of load accreditation in 2028, and assess the potential impacts they may have on its stakeholders, business processes, results of operations, cash flows and disclosures.
Revenues are impacted by both customer growth and usage, the latter of which is primarily impacted by weather, as well as impacts associated with commercial and industrial slow-downs, including economic recessions, and energy efficiencies. Very cold winters increase demand for natural gas and to a lesser extent, electricity, while warmer than normal summers increase demand for electricity, especially among residential and commercial customers. Average consumption among both electric and natural gas customers has tended to decline as more efficient appliances and furnaces are installed, and as the Company has implemented conservation programs. Natural gas weather normalization and decoupling mechanisms in certain jurisdictions have been implemented to largely mitigate the effect that would otherwise be caused by variations in volumes sold to these customers due to weather and changing consumption patterns on the Company's distribution margins.
In second half of 2023, electric fuel and purchased power prices increased across Montana-Dakota's integrated system, and remained elevated through January 2024. This was caused by transmission congestion in northwest North Dakota due to delays in additional SPP transmission line build-out, as well as additional load growth in the Bakken region. To assist in the recovery of the higher electric fuel and purchased power costs, Montana-Dakota filed waiver requests with the NDPSC and SDPUC, deferring the increased costs to the annual fuel clause adjustment. In Montana, the waiver request is filed monthly and was unopposed by the MTPSC. Effective April 1, 2024, as approved by the NDPSC, Montana-Dakota started recovery in North Dakota of these increased costs over a period of two years rather than one year. In South Dakota and Montana, Montana-Dakota recovered these costs over a one-year period effective July 1, 2024. In July 2025, the NDPSC approved Montana-Dakota's request to defer external legal expenses related to this congestion litigation and record those deferred expenses into a regulatory asset. Montana-Dakota and MISO each filed a petition for review of the FERC decision with the Eighth Circuit with a decision expected in the first half of 2026.
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The Company continues to proactively monitor and work with its manufacturers to reduce the effects of increased pricing and long lead times on delivery of certain raw materials and equipment used in electric generation, transmission and distribution system and natural gas pipeline projects. Long lead times are attributable to increased demand for steel products from pipeline companies as they continue pipeline system safety and integrity replacement projects driven by PHMSA regulations, as well as delays in the manufacturing and shipping of electrical equipment and increased demand for electrical equipment due to regulatory activity and grid expansion. The Company has been able to minimize the effects by working closely with suppliers or obtaining additional suppliers, as well as modifying project plans to accommodate extended lead times and increased costs. The Company expects these delays to continue. Inflationary pressures have moderated but costs for goods and services remain high. The Company also continues to monitor the impact tariffs will have on its costs. Tariff increases on raw materials could negatively affect the Company's construction projects and maintenance work. For additional discussion regarding risks and uncertainties, see Part II, Item 1A. Risk Factors in this quarterly report and Part I, Item 1A. Risk Factors in the 2024 Annual Report.
The ability to grow through acquisitions is subject to significant competition and acquisition premiums. In addition, the ability of the segments to grow their service territory and customer base is affected by regulatory constraints, the economic environment of the markets served, population changes and competition from other energy providers and fuel. The construction of new electric generating facilities, transmission lines and other service facilities is subject to higher costs and long lead times for equipment, extensive permitting procedures, and federal and state legislative and regulatory initiatives, which may necessitate increases in electric energy prices. As the industry continues to expand the use of renewable energy sources, the need for additional transmission infrastructure is growing. As part of MISO's long range transmission plan, in August 2022, the Company announced its intent to develop, construct and co-own JETx with Otter Tail Power Company in central North Dakota. In October 2023, the FERC issued an order approving the Company's request for CWIP Incentive Rate and Abandoned Plant Incentive treatment on this project. Montana-Dakota and Otter Tail Power Company received approval of a Certificate of Public Convenience and Necessity from the NDPSC in November 2024 on this project. The route permit for JETx line was filed with the NDPSC in August 2025. JETx is expected to be placed in service at the end of 2028.
Earnings overview - The following information summarizes the performance of the electric segment.

| Three Months Ended |  | Nine Months Ended
| September 30, |  | September 30,
| 2025 |  | 2024 |  | Variance |  | 2025 |  | 2024 |  | Variance
| (In millions)
Operating revenues | $ | 117.8 |  | $ | 108.5 |  | 8.6 | % |  | $ | 328.3 |  | $ | 315.5 |  | 4.1 | %
Operating expenses: |  |  |  |  |  |  |
Electric fuel and purchased power | 41.2 |  | 32.5 |  | 26.8 | % |  | 119.8 |  | 109.0 |  | 9.9 | %
Operation and maintenance | 26.1 |  | 23.4 |  | 11.5 | % |  | 84.6 |  | 70.1 |  | 20.7 | %
Depreciation and amortization | 17.4 |  | 16.9 |  | 3.0 | % |  | 52.0 |  | 49.7 |  | 4.6 | %
Taxes, other than income | 4.7 |  | 3.6 |  | 30.6 | % |  | 14.2 |  | 13.2 |  | 7.6 | %
Total operating expenses | 89.4 |  | 76.4 |  | 17.0 | % |  | 270.6 |  | 242.0 |  | 11.8 | %
Operating income | 28.4 |  | 32.1 |  | (11.5) | % |  | 57.7 |  | 73.5 |  | (21.5) | %
Other income | 2.0 |  | 1.4 |  | 42.9 | % |  | 5.7 |  | 5.5 |  | 3.6 | %
Interest expense | 7.6 |  | 7.6 |  | — | % |  | 23.1 |  | 22.4 |  | 3.1 | %
Income before income taxes | 22.8 |  | 25.9 |  | (12.0) | % |  | 40.3 |  | 56.6 |  | (28.8) | %
Income tax (benefit) expense | 1.3 |  | 1.6 |  | (18.8) | % |  | (6.6) |  | (1.1) |  | 500.0 | %
Net income | $ | 21.5 |  | $ | 24.3 |  | (11.5) | % |  | $ | 46.9 |  | $ | 57.7 |  | (18.7) | %

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Operating statistics | Three Months Ended |  | Nine Months Ended
| September 30, |  | September 30,
| 2025 |  | 2024 |  |  | 2025 |  | 2024 |
Revenues (millions) |  |  |  |  |
Retail sales: |  |  |  |  |
Residential | $ | 35.7 |  | $ | 36.7 |  |  | $ | 102.2 |  | $ | 106.8 |
Commercial | 50.7 |  | 44.7 |  |  | 137.1 |  | 125.7 |
Industrial | 9.5 |  | 9.5 |  |  | 27.4 |  | 32.4 |
Other | 2.0 |  | 2.0 |  |  | 5.5 |  | 6.0 |
| 97.9 |  | 92.9 |  |  | 272.2 |  | 270.9 |
Other | 19.9 |  | 15.6 |  |  | 56.1 |  | 44.6 |
| $ | 117.8 |  | $ | 108.5 |  |  | $ | 328.3 |  | $ | 315.5 |
Volumes (million kWh) |  |  |  |  |
Retail sales: |  |  |  |  |
Residential | 297.8 |  | 300.4 |  |  | 904.3 |  | 868.5 |
Commercial | 707.9 |  | 725.5 |  |  | 2,104.5 |  | 1,762.9 |
Industrial | 121.1 |  | 119.1 |  |  | 357.8 |  | 394.7 |
Other | 21.2 |  | 21.7 |  |  | 61.5 |  | 61.0 |
| 1,148.0 |  | 1,166.7 |  |  | 3,428.1 |  | 3,087.1 |
Average cost of electric fuel and purchased power per kWh | $ | .027 |  | $ | .020 |  |  | $ | .026 |  | $ | .026 |
Cooling degree days (% warmer (colder) than prior year)1
Montana | (13.0) | % | 6.4 | % |  | (4.3) | % | (3.0) | %
North Dakota | (17.0) | % | 22.0 | % |  | (6.6) | % | (4.2) | %
South Dakota | 8.6 | % | (10.4) | % |  | 18.4 | % | (28.3) | %
Wyoming | (25.2) | % | 38.2 | % |  | (22.9) | % | 42.7 | %
1 Cooling degree days are a measure of the energy demand for cooling.

Three Months Ended September 30, 2025, Compared to Three Months Ended September 30, 2024 Electric earnings decreased $2.8 million as a result of:
•Revenue increased $9.3 million, largely due to higher fuel and purchased power costs of $8.7 million recovered in customer rates and offset in expense, as described below.
•Electric fuel and purchased power increased $8.7 million, largely the result of higher commodity prices, partially offset by lower retail sales volumes.
•Operation and maintenance increased $2.7 million.
◦Largely the result of:
▪Higher payroll-related costs of $2.0 million.
▪Higher contract services related to electric generation station outage-related costs of $600,000.
◦Also reflected are higher costs associated with services provided to Everus as part of the TSA, offset in other income, as described below.
•Depreciation and amortization increased $500,000, largely due to increased property, plant, and equipment balances as a result of transmission projects placed in service to improve reliability and update aging infrastructure.
•Taxes, other than income increased $1.1 million, largely as a result of higher property tax, primarily in Montana.
•Other income increased $600,000, including higher TSA income, as described above.
•Interest expense was comparable to the same period in the prior year.
•Income tax expense decreased $300,000, largely due to lower income before income taxes.
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Nine Months Ended September 30, 2025, Compared to Nine Months Ended September 30, 2024 Electric earnings decreased $10.8 million as a result of:
•Revenue increased $12.8 million.
◦Largely due to:
▪Higher fuel and purchased power costs of $10.8 million recovered in customer rates and offset in expense, as described below.
▪Higher net transmission revenue of $1.9 million, including data center revenue.
▪Higher retail sales volumes of $1.4 million, driven primarily by higher residential volumes, largely due to colder weather in the first quarter of the year, and higher commercial volumes from the data center as further discussed in the Outlook section.
◦Partially offset by lower renewable tracker revenues, partly associated with higher production tax credits offset in income tax benefit, as described below.
•Electric fuel and purchased power increased $10.8 million, largely the result of higher retail sales volumes, partially offset by lower commodity prices.
•Operation and maintenance increased $14.5 million.
◦Largely the result of:
▪Higher payroll-related costs of $5.5 million.
▪Higher contract services related to electric generation station outage-related costs of $3.7 million.
▪Increased software expense of $3.0 million.
▪Higher insurance expense.
◦Also reflected are higher costs associated with services provided to Everus as part of the TSA, offset in other income, as described below.
•Depreciation and amortization increased $2.3 million, largely due to increased property, plant, and equipment balances as a result of transmission projects placed in service to improve reliability and update aging infrastructure.
•Taxes, other than income increased $1.0 million, largely as a result of higher property tax, primarily in Montana.
•Other income increased $200,000, including higher TSA income, as described above, partially offset by lower interest income from regulatory deferral balances.
•Interest expense increased $700,000, largely the result of lower AFUDC, partially offset by lower expense associated with lower average debt balances.
•Income tax benefit increased $5.5 million, largely due to lower income before income taxes, and higher production tax credits of $1.6 million driven by higher wind production.
Earnings overview - The following i nformation summarizes the performance of the natural gas distribution segment.

| Three Months Ended |  | Nine Months Ended
| September 30, |  | September 30,
| 2025 |  | 2024 |  | Variance |  | 2025 |  | 2024 |  | Variance
| (In millions)
Operating revenues | $ | 144.3 |  | $ | 133.6 |  | 8.0 | % |  | $ | 890.5 |  | $ | 794.6 |  | 12.1 | %
Operating expenses: |  |  |  |  |  |  |
Purchased natural gas sold | 62.7 |  | 57.3 |  | 9.4 | % |  | 519.0 |  | 449.5 |  | 15.5 | %
Operation and maintenance | 56.7 |  | 54.8 |  | 3.5 | % |  | 180.8 |  | 169.2 |  | 6.9 | %
Depreciation and amortization | 26.6 |  | 25.0 |  | 6.4 | % |  | 79.2 |  | 76.1 |  | 4.1 | %
Taxes, other than income | 13.3 |  | 11.2 |  | 18.8 | % |  | 60.9 |  | 55.1 |  | 10.5 | %
Total operating expenses | 159.3 |  | 148.3 |  | 7.4 | % |  | 839.9 |  | 749.9 |  | 12.0 | %
Operating income (loss) | (15.0) |  | (14.7) |  | 2.0 | % |  | 50.6 |  | 44.7 |  | 13.2 | %
Other income | 3.9 |  | 6.0 |  | (35.0) | % |  | 12.3 |  | 19.5 |  | (36.9) | %
Interest expense | 14.7 |  | 15.9 |  | (7.5) | % |  | 43.3 |  | 46.9 |  | (7.7) | %
Income (loss) before income taxes | (25.8) |  | (24.6) |  | 4.9 | % |  | 19.6 |  | 17.3 |  | 13.3 | %
Income tax (benefit) expense | (7.6) |  | (7.1) |  | 7.0 | % |  | 0.5 |  | (0.3) |  | (266.7) | %
Net income (loss) | $ | (18.2) |  | $ | (17.5) |  | 4.0 | % |  | $ | 19.1 |  | $ | 17.6 |  | 8.5 | %

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Operating statistics | Three Months Ended |  | Nine Months Ended
| September 30, |  | September 30,
| 2025 |  | 2024 |  |  | 2025 |  | 2024 |
Revenues (millions) |  |  |  |  |
Retail sales: |  |  |  |  |
Residential | $ | 67.5 |  | $ | 62.6 |  |  | $ | 465.2 |  | $ | 434.7 |
Commercial | 43.7 |  | 38.5 |  |  | 296.7 |  | 265.1 |
Industrial | 8.0 |  | 6.9 |  |  | 33.1 |  | 30.8 |
| 119.2 |  | 108.0 |  |  | 795.0 |  | 730.6 |
Transportation and other | 25.1 |  | 25.6 |  |  | 95.5 |  | 64.0 |
| $ | 144.3 |  | $ | 133.6 |  |  | $ | 890.5 |  | $ | 794.6 |
Volumes (MMdk) |  |  |  |  |
Retail sales: |  |  |  |  |
Residential | 3.9 |  | 3.7 |  |  | 44.2 |  | 43.4 |
Commercial | 4.7 |  | 3.6 |  |  | 33.6 |  | 30.8 |
Industrial | .9 |  | 1.0 |  |  | 3.6 |  | 4.0 |
| 9.5 |  | 8.3 |  |  | 81.4 |  | 78.2 |
Transportation sales: |  |  |  |  |
Commercial | .3 |  | .3 |  |  | 1.4 |  | 1.3 |
Industrial | 42.6 |  | 45.1 |  |  | 129.1 |  | 141.6 |
| 42.9 |  | 45.4 |  |  | 130.5 |  | 142.9 |
Total throughput | 52.4 |  | 53.7 |  |  | 211.9 |  | 221.1 |
Average cost of natural gas per dk | $ | 6.59 |  | $ | 6.91 |  |  | $ | 6.38 |  | $ | 5.75 |
Heating degree days (% colder (warmer) than prior year)1
Idaho | (36.0) | % | (23.1) | % |  | (2.0) | % | (11.5) | %
Minnesota | 138.1 | % | (4.5) | % |  | 17.5 | % | (21.4) | %
Montana | — | % | (20.6) | % |  | 6.4 | % | (5.9) | %
North Dakota 2 | 80.0 | % | (16.7) | % |  | 13.1 | % | (17.0) | %
Oregon 2 | (17.7) | % | (36.7) | % |  | (1.7) | % | (7.0) | %
South Dakota 2 | 23.8 | % | (43.2) | % |  | 9.8 | % | (12.0) | %
Washington 2 | (59.1) | % | (7.0) | % |  | (4.8) | % | 0.9 | %
Wyoming | 37.8 | % | (9.8) | % |  | 10.8 | % | (13.3) | %
1 Heating Degree days are a measure of the daily temperature demand for energy heating. 2 Weather normalization or decoupling mechanisms are in place that minimize the weather impact.

Three Months Ended September 30, 2025, Compared to Three Months Ended September 30, 2024 Natural gas distribution reported an increased seasonal loss of $700,000 as a result of:
•Revenue increased $10.7 million.
◦Largely due to:
▪Higher purchased natural gas sold of $5.4 million, including net environmental compliance costs, recovered in customer rates and offset in expense, as described below.
▪Rate relief of $3.7 million, primarily in Washington and Montana.
▪Higher basic service charges of $800,000 due to customer growth.
▪Higher revenue-based taxes of $700,000, recovered in rates and offset in expense, as described below.
•Purchased natural gas sold increased $5.4 million, largely due to higher volumes of natural gas purchased of $8.4 million. This increase was partially offset by lower commodity costs of $1.5 million and net environmental compliance costs of $1.5 million.
•Operation and maintenance increased $1.9 million.
◦Largely due to:
▪Higher payroll-related costs of $1.3 million.
▪Higher costs associated with MAOP projects.
◦Also reflected are higher costs associated with services provided to Everus as part of the TSA, offset in other income, as described below.
•Depreciation and amortization increased $1.6 million, of which $2.0 million resulted from increased property, plant and equipment balances related to growth and replacement projects placed in service, partially offset by lower depreciation rates implemented from rates cases in North Dakota, Montana and Wyoming of $500,000.
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•Taxes, other than income increased $2.1 million, due to higher property taxes, largely in Montana and Washington, and higher revenue-based taxes recovered in rates, as described above.
•Other income decreased $2.1 million, primarily due to lower interest income on regulatory deferral balances, partially offset by higher TSA revenue, as described above.
•Interest expense decreased $1.2 million, primarily from lower long-term interest expense, largely due to lower long-term debt balances.
•Income tax benefit increased $500,000, primarily the result of higher seasonal loss before income taxes and changes in permanent tax adjustments.
Nine Months Ended September 30, 2025, Compared to Nine Months Ended September 30, 2024 Natural gas distribution earnings increased $1.5 million as a result of:
•Revenue increased $95.9 million.
◦Largely due to:
▪Higher purchased natural gas sold of $69.5 million, including net environmental compliance costs, recovered in customer rates and offset in expense, as described below.
▪Rate relief of $16.3 million, primarily in Washington, Montana and South Dakota.
▪Higher revenue-based taxes of $4.7 million, recovered in rates and offset in expense, as described below.
▪Higher retail sales volumes of $2.6 million, which includes weather normalization and decoupling mechanisms in certain jurisdictions, and higher volumes to commercial and residential customer classes, largely due to colder weather in certain jurisdictions.
▪Higher conservation revenues of $2.6 million, offset in expense, as described below.
▪Higher basic service charges of $1.6 million due to customer growth.
•Purchased natural gas sold increased $69.5 million, largely due to net environmental compliance costs of $46.2 million, higher volumes of natural gas purchased of $19.5 million and higher commodity costs of $3.8 million.
•Operation and maintenance increased $11.6 million.
◦Largely due to:
▪Higher payroll-related costs of $4.6 million.
▪Higher conservation-related costs, recovered in rates, as discussed above.
▪Higher costs associated with MAOP projects of $1.2 million.
▪Higher software-related expense of $1.1 million.
▪Higher insurance expense.
◦Also reflected are higher costs associated with services provided to Everus as part of the TSA, offset in other income, as described below.
•Depreciation and amortization increased $3.1 million, of which $5.2 million resulted from increased property, plant and equipment balances related to growth and replacement projects placed in service, partially offset by lower depreciation rates implemented from rates cases in North Dakota, Montana and Wyoming of $1.4 million, and lower regulatory amortizations.
•Taxes, other than income increased $5.8 million, due to higher revenue-based taxes, as described above, and higher property taxes, largely in Montana and Washington.
•Other income decreased $7.2 million.
◦Primarily due to:
▪Lower interest on regulatory deferral balances.
▪The absence of $2.2 million of interest income associated with prior year renewable natural gas projects.
▪Higher pension expense of $1.0 million.
▪Lower returns of $1.0 million on the Company's nonqualified benefit plans.
◦Offset in part by higher TSA revenue, as described above.
•Interest expense decreased $3.6 million, primarily from lower long-term interest expense, largely due to lower long-term debt balances.
•Income tax expense increased $800,000, primarily the result of changes in permanent tax adjustments and higher income before income taxes.
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Outlook In 2024, the utility business experienced rate base growth of 6.8 percent and expects these segments will grow rate base by approximately 7 percent to 8 percent annually over the next five years on a compound basis. Operations are spread across eight states where the Company expects customer growth to be higher than the national average. In 2024, these segments experienced retail customer growth of approximately 1.4 percent and the Company expects customer growth to continue to average 1 percent to 2 percent per year. This customer growth, along with system upgrades and replacements needed to supply safe and reliable service, will require investments in new and replacement electric and natural gas systems.
These segments are exposed to energy price volatility and may be impacted by changes in oil and natural gas exploration and production activity. Rate schedules in the jurisdictions in which the Company's natural gas distribution segment operates contain clauses that permit the Company to file for rate adjustments for changes in the cost of purchased natural gas. Although changes in the price of natural gas are passed through to customers and have minimal impact on the Company's earnings, the natural gas distribution segment's customers benefit from lower natural gas prices through the Company's utilization of storage and fixed price contracts.
The EPA's GHG and mercury emissions standards finalized in May 2024 would have required additional pollution controls for Coyote Station to operate beyond 2031 and 2027, respectively. In April 2025, the EPA granted a two year extension for Coyote Station to add pollution controls to comply with the mercury emissions standard. In June 2025, the EPA proposed rules to repeal both the mercury emissions standard and the electric generation GHG emissions standard. If the rules go into effect, it could require owners of Coyote station to incur significant new costs. These costs could, dependent on determination by state regulatory commissions on approval to recover such costs from customers, negatively impact the Company's results of operations, financial position and cash flows. In December 2024, the EPA issued a final decision on the NDDEQ's Regional Haze state implementation plan, maintaining the proposed disapproval of the state's conclusion that no additional controls are warranted during this implementation period. The EPA did not issue a federal implementation plan in place of the state plan and would have two years from the state plan disapproval to either propose a federal plan or approve a new state plan. Coyote Station co-owners filed a petition for review with the Eighth Circuit in January 2025, challenging EPA's NDDEQ state plan disapproval, and in February 2025, filed a petition for reconsideration with the EPA, which was granted in April 2025. In June 2025, the Eighth Circuit granted a request by the EPA to continue to hold the petition of review proceeding in abeyance so that the EPA could review the previous administration's findings and actions. In March 2025, the EPA announced the agency is restructuring the regulations for implementing the Regional Haze Program. Further, in October 2025, the EPA released an advanced notice of proposed rulemaking seeking input on restructuring the program with the intent to streamline regulatory requirements for states' visibility improvement obligations. The Company is one of four owners of Coyote Station and cannot make a unilateral decision on the plant's future; therefore, the Company could be negatively impacted by decisions of the other owners. The joint owners continue to collaborate in analyzing data and weighing decisions that impact the plant and its employees as well as each company's customers and communities served.
In February 2025, Montana-Dakota entered into a definitive purchase and sale agreement with Badger Wind, LLC, a subsidiary of Orsted Onshore North America, LLC. Pursuant to the terms of the agreement, Montana-Dakota will purchase a 49 percent undivided ownership interest in a wind project being constructed and located in North Dakota that is anticipated to have a net generating capacity of approximately 250 MW for a purchase price of $294.0 million, which would represent 122.5 MW of wind generation to be owned by Montana-Dakota. In September 2025, the NDPSC granted an advanced determination of prudence and certificate of public convenience and necessity. The project is expected to be completed near the end of 2025. This transaction would reduce Montana-Dakota's purchase requirements under the existing power purchase agreement with Badger Wind, LLC, dated November 4, 2024.
In March 2023, the Company began to provide power for Applied Digital's data center near Ellendale, North Dakota. At full capacity, the data center requires 180 MW of electricity, which is the equivalent of about 28 percent of the Company's generation portfolio. Applied Digital's load is purchased from the MISO market and does not impact other customers' power supply. An electric service agreement to serve an additional 350 MW data center load with Applied Digital in the Company's service territory was approved by the NDPSC. 100 MW of the additional data center load is expected to be fully online in the second quarter of 2026.
In August 2024, the Company filed a request with the SDPUC seeking approval on an electric service agreement to provide up to 50 MW of electricity to a data center near Leola, South Dakota. Construction of the data center and approval of the electric service agreement which had been pending development of new local siting requirements for data center loads by McPherson County in South Dakota, were effective August 5, 2025. Approval of the electric service agreement with the SDPUC is still pending final approvals of the data center siting with McPherson County.
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The Infrastructure Investment and Jobs Act, commonly known as the Bipartisan Infrastructure Law, was enacted in the fourth quarter of 2021 designating funds for investments such as upgrades to electric and grid infrastructure, transportation systems, and electric vehicle infrastructure. In July 2025, the North Dakota Industrial Commission awarded the Company a grant award under the Grid Resilience and Innovative Partnerships Program, which is part of the Infrastructure Investment and Jobs Act. The funds from the award will be used by the Company to build a 46 kV transmission line that will connect the Merricourt Transmission Substation to a 46 kV line near Fredonia, North Dakota. In addition, the IRA provided new funding for clean energy programs. The Company continues to pursue various opportunities under the Grid Resilience and Innovative Partnerships Program, and is also pursuing a biogas property at the Knott Landfill site in Bend, Oregon which may qualify for an investment tax credit and clean fuel production credits as part of the IRA. As discussed previously, the Company is evaluating the impact the OBBBA may have on these projects.
Legislation and rulemaking The Company continues to monitor legislation and rulemaking related to clean energy standards that may impact its segments. Below are some of the specific actions the Company is monitoring.
•In May 2024, the EPA published four final rules, three of which will impose stricter standards on GHG emissions from existing coal-fired and new natural gas-fired generation units, require a further reduction of mercury emissions from coal-fired generation units, and impose additional regulations around the storage and management of coal ash. In March 2025, the EPA announced reconsideration of the Electric Generation and Greenhouse Gas Rule, Mercury and Air Toxics Standards Rule, and Effluent Limitations Guidelines Rule. Comments on certain of these proposed rules were due in August 2025. If the rules were to remain as originally proposed and if the costs to comply with these rules are not fully recoverable from customers, they could have a material adverse effect on the Company's results of operations and cash flows.
•In July 2025, the EPA released a new proposed rule, Reconsideration of 2009 Endangerment Finding and Greenhouse Gas Vehicle Standards, to repeal the EPA's 2009 determination. This proposal would undo the basis for federal regulation of GHG's under the Clean Air Act. The Company is evaluating the proposal.
•In July 2024, the ODEQ released the Climate Protection Program Rule, which was adopted by the Oregon Environmental Quality Commission in November 2024. The Company intends to meet its obligations through surrendering no cost emissions allowances and will fill remaining compliance obligations by investing in additional customer conservation and energy efficiency programs, purchasing community climate investment credits, and low carbon fuel projects such as RNG and purchasing associated environmental attributes. Compliance costs for these regulations are being recovered through customer rates. Due to the timing of regulatory recovery, future compliance obligation purchases could impact the Company's operating cash flow.
•In Washington, the Climate Commitment Act was effective in 2023. Compliance costs for these regulations are being recovered through customer rates. Due to the timing of regulatory recovery, the purchase of allowances could impact the Company's operating cash flow.
•The Washington SBCC in November and December 2023, adopted residential and commercial building code amendments that will significantly limit the use of natural gas for space and water heating in new and retrofitted commercial and multifamily buildings and proposed the review of similar restrictions in the future for residential buildings. In May 2024, the Company filed a joint complaint seeking declaratory and injunctive relief under federal law against the Washington SBCC's adoption of the Washington State Energy Code. This complaint was dismissed by the federal district court. Petitioners have appealed this decision to the United States Court of Appeals for the Ninth Circuit. The Company's opening brief was filed in July 2025.
Initiative Measure No. 2066, which was approved by voters, prohibits the Washington State Energy Code from "in any way prohibit, penalize, or discourage the use of gas for any form of heating, or for uses related to any appliance or equipment, in any building." In May 2025, the King County Superior Court filed an order ruling Initiative Measure No. 2066 unconstitutional. Following the ruling, the Building Industry Association of Washington filed a notice of appeal with the King County Superior Court. Instead of transferring to the Court of Appeals, Initiative Measure No. 2066 is now pending review by the Washington State Supreme Court.
•In March 2024, the SEC issued Final Rule 33-11275 - The Enhancement and Standardization of Climate-Related Disclosures for Investors. In April 2024, the SEC announced that it would voluntarily stay its final climate disclosure rules pending judicial review. In March 2025, the SEC withdrew its defense of the rules. In July 2025, the SEC asked the Eighth Circuit to issue a ruling on the abandoned climate regulations. In September 2025, the Eighth Circuit stated it was pausing its consideration of legal challenges against this rule, pending further action by the SEC.
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Pipeline
Strategy and challenges The pipeline segment provides natural gas transportation, underground storage and energy-related services, including cathodic protection, as discussed in Note 15. The segment focuses on utilizing its extensive expertise in the design, construction and operation of energy infrastructure and related services to increase market share and profitability through optimization of existing operations, organic growth and investments in energy-related assets within or in close proximity to its current operating areas. The segment focuses on the continual safety and reliability of its systems, which entails building, operating and maintaining safe natural gas pipelines and facilities. The segment continues to evaluate growth opportunities including the expansion of natural gas facilities; incremental pipeline projects; and expansion of energy-related services leveraging on its core competencies. In support of this strategy, the Company completed the following growth projects in 2024 and 2025:
•In March 2024, the 2023 Line Section 27 Expansion project was placed in service and increased system capacity by 175 MMcf of natural gas per day.
•In July 2024, the Line Section 28 Expansion project was placed in service and increased system capacity by 137 MMcf of natural gas per day.
•In November 2024, the Company closed on the purchase of a 28-mile natural gas pipeline lateral in northwestern North Dakota.
•In December 2024, the Wahpeton Expansion Project was placed in service and increased system capacity by approximately 20 MMcf of natural gas per day.
•In November 2025, the Minot Expansion Project was placed in service and increased system capacity by 7 MMcf of natural gas per day.
The segment is exposed to natural gas and oil price volatility including fluctuations in basis differentials. Legislative and regulatory initiatives on increased pipeline safety regulations and environmental matters such as the reduction of methane emissions could also impact the price and demand for natural gas.
The pipeline segment is subject to extensive regulation related to certain operational and environmental compliance, cybersecurity, permit terms and system integrity. The Company continues to actively evaluate cybersecurity processes and procedures, including changes in the industry's cybersecurity regulations, for opportunities to further strengthen its cybersecurity protections. Implementation of enhancements and additional requirements is ongoing. The segment reviews and secures existing permits and easements, as well as new permits and easements as necessary, to meet current demand and future growth opportunities on an ongoing basis.
Tariff increases on raw materials could negatively affect the Company's construction projects and maintenance work. The Company continues to monitor the impact tariffs will have on its costs. The Company continues to actively manage the national supply chain challenges by working with its manufacturers and suppliers to help mitigate some of these risks on its business. The segment regularly experiences extended lead times on raw materials that are critical to the segment's construction and maintenance work which could delay maintenance work and construction projects potentially causing lost revenues and/or increased costs. The Company is partially mitigating these challenges by planning for extended lead times further in advance. The Company expects these delays to continue. Inflationary pressures have moderated, but costs for raw material and contract services remain high. For additional discussion regarding risks and uncertainties, see Part II, Item 1A. Risk Factors in this quarterly report and Part I, Item 1A. Risk Factors in the 2024 Annual Report.
The segment focuses on the recruitment and retention of a skilled workforce to remain competitive and provide services to its customers. The industry in which it operates relies on a skilled workforce to construct energy infrastructure and operate existing infrastructure in a safe manner. A shortage of skilled personnel can create a competitive labor market which could increase costs incurred by the segment. Competition from other pipeline companies can also have a negative impact on the segment.
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Earnings overview - The following information summarizes the performance of the pipeline segment.

| Three Months Ended |  | Nine Months Ended
| September 30, |  | September 30,
| 2025 |  | 2024 |  | Variance |  | 2025 |  | 2024 |  | Variance
| (In millions)
Operating revenues | $ | 57.4 |  | $ | 51.5 |  | 11.5 | % |  | $ | 170.4 |  | $ | 155.8 |  | 9.4 | %
Operating expenses: |  |  |  |  |  |  |
Operation and maintenance | 21.0 |  | 19.0 |  | 10.5 | % |  | 62.7 |  | 56.8 |  | 10.4 | %
Depreciation and amortization | 8.1 |  | 7.4 |  | 9.5 | % |  | 24.0 |  | 21.8 |  | 10.1 | %
Taxes, other than income | 3.7 |  | 3.0 |  | 23.3 | % |  | 10.6 |  | 9.1 |  | 16.5 | %
Total operating expenses | 32.8 |  | 29.4 |  | 11.6 | % |  | 97.3 |  | 87.7 |  | 10.9 | %
Operating income | 24.6 |  | 22.1 |  | 11.3 | % |  | 73.1 |  | 68.1 |  | 7.3 | %
Other income | 1.0 |  | 1.3 |  | (23.1) | % |  | 3.1 |  | 5.3 |  | (41.5) | %
Interest expense | 4.1 |  | 3.6 |  | 13.9 | % |  | 12.6 |  | 11.4 |  | 10.5 | %
Income before income taxes | 21.5 |  | 19.8 |  | 8.6 | % |  | 63.6 |  | 62.0 |  | 2.6 | %
Income tax expense | 4.7 |  | 4.7 |  | — | % |  | 14.2 |  | 14.5 |  | (2.1) | %
Net income | $ | 16.8 |  | $ | 15.1 |  | 11.3 | % |  | $ | 49.4 |  | $ | 47.5 |  | 4.0 | %

Operating statistics | Three Months Ended |  | Nine Months Ended
| September 30, |  | September 30,
| 2025 |  | 2024 |  |  | 2025 |  | 2024 |
Transportation volumes (MMdk) | 160.3 |  | 155.1 |  |  | 455.2 |  | 463.5 |
Customer natural gas storage balance (MMdk): |  |  |  |  |
Beginning of period | 34.6 |  | 41.4 |  |  | 44.1 |  | 37.7 |
Net injection | 13.6 |  | 13.2 |  |  | 4.1 |  | 16.9 |
End of period | 48.2 |  | 54.6 |  |  | 48.2 |  | 54.6 |

Three Months Ended September 30, 2025, Compared to Three Months Ended September 30, 2024 Pipeline earnings increased $1.7 million as a result of:
•Revenues increased $5.9 million as a result of:
◦Increased demand revenue, largely due to:
▪Growth projects placed in service in late 2024 of $2.7 million.
▪Increased usage of short-term natural gas transportation contracts of $1.3 million.
▪Partially offset by the expiration of certain contracts.
◦Higher interruptible transportation volumes of $1.2 million.
◦Higher non-regulated project revenue of $600,000.
•Operation and maintenance increased $2.0 million.
◦Primarily from:
▪Higher payroll-related costs of $600,000.
▪Higher non-regulated project costs of $500,000, associated with increased non-regulated project revenue as previously discussed.
▪Also reflected are higher costs associated with services provided to Everus as part of TSA, offset in other income, as described below.
▪Higher other costs including insurance.
•Depreciation and amortization increased $700,000 driven largely by higher property, plant and equipment balances related to growth projects placed in service as previously discussed.
•Taxes, other than income increased $700,000, largely due to higher property tax valuations in Montana.
•Other income decreased $300,000,
◦Primarily due to:
▪Lower interest income.
▪Lower AFUDC for the construction of the Company's growth projects.
◦Partially offset by higher TSA income, as described above.
•Interest expense increased $500,000, primarily from higher debt rates and lower AFUDC, as previously discussed.
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•Income tax expense was comparable to the same period in the prior year, largely due to higher income before taxes offset by a decrease in the state effective tax rate largely due to growth in North Dakota.
Nine Months Ended September 30, 2025, Compared to Nine Months Ended September 30, 2024 Pipeline earnings increased $1.9 million as a result of:
•Revenues increased $14.6 million as a result of:
◦Increased demand revenue, largely due to:
▪Growth projects placed in service throughout 2024 of $9.4 million.
▪Increased usage of short-term natural gas transportation contracts of $3.7 million.
▪Higher storage related revenue of $1.1 million.
▪Partially offset by the expiration of certain contracts.
◦Higher interruptible transportation volumes of $1.7 million.
◦Higher non-regulated project revenue of $500,000.
•Operation and maintenance increased $5.9 million.
◦Primarily from:
▪Higher payroll-related costs of $2.8 million.
▪Higher costs associated with services provided to Everus as part of the TSA, offset in other income, as described below.
▪Higher non-regulated project costs of $800,000, associated with increased non-regulated project revenue as previously discussed.
▪Higher other costs including insurance and contract services.
•Depreciation and amortization increased $2.2 million driven largely by higher property, plant and equipment balances related to growth projects placed in service, as previously discussed.
•Taxes, other than income increased $1.5 million, largely due to higher property tax valuations in Montana.
•Other income decreased $2.2 million,
◦Primarily due to:
▪The absence of proceeds received in 2024 from a customer settlement of $2.0 million.
▪Lower interest income.
▪Lower AFUDC, as previously discussed.
▪Partially offset by higher TSA income of $1.2 million, as described above.
•Interest expense increased $1.2 million, primarily from higher debt balances to fund capital expenditures and lower AFUDC, as previously discussed.
•Income tax expense decreased $300,000, primarily from a decrease in the state effective tax rate largely due to growth in North Dakota, partially offset by higher income before income taxes.
Outlook The Company has continued to experience the effect of associated natural gas production in the Bakken, which has provided opportunities for organic growth projects and increased transportation demand. The completion of organic growth projects has contributed to higher volumes of natural gas the Company transports through its system. Bakken natural gas production is currently at or near record levels and the outlook remains positive with continued growth expected due to new oil wells and increasing gas to oil ratios.
Increases in national and global natural gas supply have moderated pressure on natural gas prices and price volatility. While the Company believes there will continue to be varying pressures on natural gas production levels and prices, the long-term outlook for natural gas prices continues to provide growth opportunities for supply and demand related projects and seasonal pricing differentials provide opportunities for natural gas storage services.
The Company continues to monitor, evaluate and implement additional GHG emissions reduction strategies, including increased monitoring frequency and emission source control technologies to minimize potential risk.
In 2024, the EPA published several final rules related to GHG emissions from the oil and natural gas industry. These rules update, strengthen and expand standards to reduce GHG emissions and other air pollutants from new and existing oil and gas facilities, revise the GHG reporting rules and incorporate the Waste Emissions Charge provisions from the IRA. In first quarter 2025, Congress passed a resolution of disapproval overturning the Waste Emissions Charge regulations and President Trump signed the resolution, eliminating the rule. On July 4, 2025, the OBBBA postponed the Waste Emissions Charge provisions in the Clean Air Act to 2034. Also, the EPA Administrator announced "31 Historic Actions to Power the Great American Comeback" which includes plans for reconsideration of several EPA rules related to GHG emissions from the oil and natural gas industry. The EPA has since issued several actions including interim final rules extending deadlines for certain oil and gas new source performance standards and a proposal to reconsider the Greenhouse Gas Reporting Program. The Company continues to comply with rules as they remain effective, and to monitor and assess these rulemakings and the potential impacts they may have on its business processes, current and future projects, results of operations and disclosures.
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The Company continues to focus on improving existing operations and on growth opportunities through organic expansion projects in all areas in which it operates, which includes additional projects with local distribution companies, Bakken area producers, electric generation customers and industrial customers in various stages of development, including:
•Line Section 32 Expansion project which will provide natural gas transportation service to a new electric generation facility in northwest North Dakota. The project consists of approximately 20 miles of pipe and ancillary facilities and is designed to increase natural gas transportation capacity by 190 MMcf per day, which is supported by a long-term customer agreement. The project is dependent on regulatory approvals and targeted to be in service in late 2028.
•Potential Bakken East Pipeline project, which could consist of 350 miles of pipeline construction from western North Dakota to the eastern part of the state, plus additional pipeline laterals. The Company continues actively marketing the project and is actively working with landowners to conduct environmental and civil surveys along the potential route. In August 2025, the North Dakota Industrial Commission selected the project for firm capacity commitments of up to $50 million annually for 10 years.
•Potential Minot Industrial Pipeline Project, which could consist of an approximately 90-mile pipeline from Tioga, North Dakota to Minot, North Dakota and ancillary facilities. The Company has signed an agreement to support the early stage development of the project. The project would provide incremental natural gas transportation capacity for anticipated industrial demand.
•A binding open season for a potential Baker Storage Field Enhancement and associated transportation expansion project concluded in May 2025. Given the project costs and current customer interest, the project is on hold but may be reevaluated in the future.
See Capital Expenditures within this section for information on the expenditures related to these growth projects.
Other

| Three Months Ended |  | Nine Months Ended
| September 30, |  | September 30,
| 2025 |  | 2024 |  | Variance |  | 2025 |  | 2024 |  | Variance
| (In millions)
Operating revenues | $ | .3 |  | $ | — |  | 100.0 | % |  | $ | .6 |  | $ | 0.1 |  | 500.0 | %
Operating expenses: |  |  |  |  |  |  |
Operation and maintenance | (1.5) |  | 4.1 |  | (136.6) | % |  | (1.0) |  | 13.3 |  | (107.5) | %
Depreciation and amortization | — |  | .6 |  | (100.0) | % |  | — |  | 1.7 |  | (100.0) | %
Taxes, other than income | — |  | — |  | — | % |  | — |  | .3 |  | (100.0) | %
Total operating expenses | (1.5) |  | 4.7 |  | (131.9) | % |  | (1.0) |  | 15.3 |  | (106.5) | %
Operating income (loss) | 1.8 |  | (4.7) |  | 138.3 | % |  | 1.6 |  | (15.2) |  | (110.5) | %
Other income | 2.0 |  | 4.2 |  | (52.4) | % |  | 5.0 |  | 13.8 |  | (63.8) | %
Interest expense | 1.6 |  | 4.1 |  | (61.0) | % |  | 3.5 |  | 12.5 |  | (72.0) | %
Income (loss) before income taxes | 2.2 |  | (4.6) |  | (147.8) | % |  | 3.1 |  | (13.9) |  | (122.3) | %
Income tax (benefit) expense | 3.9 |  | 1.7 |  | 129.4 | % |  | 3.5 |  | (1.7) |  | (305.9) | %
Loss from continuing operations | (1.7) |  | (6.3) |  | (73.0) | % |  | (.4) |  | (12.2) |  | (96.7) | %
Discontinued operations, net of tax | — |  | 49.0 |  | (100.0) | % |  | (.9) |  | 115.3 |  | (100.8) | %
Net income (loss) | $ | (1.7) |  | $ | 42.7 |  | (104.0) | % |  | $ | (1.3) |  | $ | 103.1 |  | (101.3) | %

On October 31, 2024, the company completed the separation of Everus, its former construction services business, into a new independent publicly-traded company. As a result of the separation, the historical results of operations for Everus are shown in discontinued operation, net of tax, except for allocated general corporate overhead costs of the Company which did not meet the criteria for discontinued operations. Also included in discontinued operations are strategic initiative costs associated with the separation of Everus.
Three and Nine Months Ended September 30, 2025, Compared to Three and Nine Months Ended September 30, 2024, respectively.
For the quarter and year to date, Other reported decreased net income compared to the same periods in 2024. The decreases were primarily due to the absence of income from discontinued operations in 2025 and income tax adjustments related to the Company's annualized estimated tax rate. Partially offsetting the decreases were lower operation and maintenance expenses, primarily a result of corporate overhead costs classified as continuing operations allocated to Everus in 2024, which are not included in Other in 2025, and lower insurance claims experience at the captive insurer.
Also included in Other is general and administrative costs and interest expense previously allocated to the exploration and production and refining business that did not meet the criteria for discontinued operations.
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Intersegment Transactions
Amounts presented in the preceding tables will not agree with the Consolidated Statements of Income due to the Company's elimination of intersegment transactions. The amounts related to these items were as follows:

| Three Months Ended |  | Nine Months Ended
| September 30, |  | September 30,
| 2025 |  | 2024 |  |  | 2025 |  | 2024 |
| (In millions)
Intersegment transactions: |  |  |  |  |
Operating revenues | $ | 4.7 |  | $ | 4.0 |  |  | $ | 48.7 |  | $ | 43.5 |
Purchased natural gas sold | 4.2 |  | 3.9 |  |  | 47.3 |  | 43.0 |
Operation and maintenance | .5 |  | .1 |  |  | 1.4 |  | .5 |
Other income | 1.7 |  | 3.9 |  |  | 3.9 |  | 12.9 |
Interest expense | 1.7 |  | 3.9 |  |  | 3.9 |  | 12.9 |

For more information on intersegment eliminations, see Note 15.
Liquidity and Capital Commitments
At September 30, 2025, the Company had cash, cash equivalents and restricted cash of $75.9 million and available borrowing capacity of $430.7 million under the outstanding credit facilities of the Company and its subsidiaries. The Company expects to meet its obligations for debt maturing within one year and its other operating and capital requirements from various sources, including internally generated funds; credit facilities and commercial paper of the Company and its subsidiaries, as described in Capital resources; and issuance of debt and equity securities if necessary.
Cash flows

| Nine Months Ended
| September 30,
| 2025 |  | 2024 |
| (In millions)
Net cash provided by (used in): |  |
Operating activities | $ | 392.8 |  | $ | 441.8 |
Investing activities | (359.8) |  | (392.5) |
Financing activities | (24.0) |  | (22.3) |
Increase in cash, cash equivalents and restricted cash | 9.0 |  | 27.0 |
Cash, cash equivalents and restricted cash -- beginning of year | 66.9 |  | 77.0 |
Cash, cash equivalents and restricted cash -- end of period* | $ | 75.9 |  | $ | 104.0 |
*Includes cash of discontinued operations of $15.7 million at September 30, 2024.

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Operating activities

| Nine Months Ended |
| September 30, |
| 2025 |  | 2024 |  | Variance |
| (In millions) |
Components of net cash provided by operating activities: |  |  |  |
Net income | $ | 114.1 |  | $ | 226.0 |  | $ | (111.9) |  |
(Loss) income from discontinued operations, net of tax | (.9) |  | 115.4 |  | (116.3) |  |
Income from continuing operations | 115.0 |  | 110.6 |  | 4.4 |  |
Adjustments to reconcile net income to net cash provided by operating activities | 148.4 |  | 146.6 |  | 1.8 |  |
Changes in current assets and liabilities, net of acquisitions: |  |  |  |
Receivables | 136.3 |  | 128.1 |  | 8.2 |  |
Inventories | (.6) |  | (2.1) |  | 1.5 |  |
Other current assets | 47.6 |  | 39.3 |  | 8.3 |  |
Accounts payable | (47.7) |  | (60.1) |  | 12.4 |  |
Other current liabilities | 13.8 |  | 16.3 |  | (2.5) |  |
Pension & postretirement benefit plan contributions | (2.8) |  | (2.8) |  | — |  |
Other noncurrent changes | (16.5) |  | (23.3) |  | 6.8 |  |
Net cash provided by continuing operations | 393.5 |  | 352.6 |  | 40.9 |  |
Net cash (used in) provided by discontinued operations | (.7) |  | 89.2 |  | (89.9) |  |
Net cash provided by operating activities | $ | 392.8 |  | $ | 441.8 |  | $ | (49.0) |  |

The changes in cash flows from operating activities generally follow the results of operations, as discussed in Business Segment Financial and Operating Data, and are affected by changes in working capital.
The decrease in cash flows provided by operating activities in 2025 from 2024 was largely driven by the absence of cash provided by discontinued operations in 2024. Partially offsetting the decrease was higher 2025 payable balances of power purchases at the electric business and the collection of purchased gas cost balances, including net environmental compliance costs, and higher collection of accounts receivable associated with higher gas costs in December 2024, all at the natural gas distribution business.
Investing activities

| Nine Months Ended |
| September 30, |
| 2025 |  | 2024 |  | Variance |
| (In millions) |
Components of net cash used in investing activities: |  |  |  |
Capital expenditures | $ | (353.8) |  | $ | (366.5) |  | $ | 12.7 |  |
Cost of removal, net of salvage value | (7.7) |  | (6.2) |  | (1.5) |  |
Investments | (3.3) |  | (3.3) |  | — |  |
Proceeds from investment excess cash and cost basis withdrawal | 5.0 |  | 9.0 |  | (4.0) |  |
Net cash used in continuing operations | (359.8) |  | (367.0) |  | 7.2 |  |
Net cash used in discontinued operations | — |  | (25.5) |  | 25.5 |  |
Net cash used in investing activities | $ | (359.8) |  | $ | (392.5) |  | $ | 32.7 |  |

The cash used in investing activities decreased as compared to 2024, primarily due to the absence of cash used in discontinued operations in 2024. Also contributing was lower capital expenditures at the pipeline business, primarily due to the absence of the Wahpeton Expansion project expenditures, which was partially offset by higher capital expenditures at the electric business, largely the Badger Wind project payment.
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Index
Financing activities

| Nine Months Ended |
| September 30, |
| 2025 |  | 2024 |  | Variance |
| (In millions) |
Components of net cash used in financing activities: |  |  |  |
Repayment of short-term borrowings | $ | — |  | $ | (95.0) |  | $ | 95.0 |  |
Issuance of long-term debt | 123.1 |  | 302.4 |  | (179.3) |  |
Repayment of long-term debt | (62.8) |  | (147.7) |  | 84.9 |  |
Debt issuance costs | (.2) |  | (2.4) |  | 2.2 |  |
Costs of issuance of common stock | — |  | (.1) |  | .1 |  |
Dividends paid | (79.6) |  | (76.9) |  | (2.7) |  |
Tax withholding on stock-based compensation | (4.5) |  | (2.6) |  | (1.9) |  |
Net cash used in continuing operations | (24.0) |  | (22.3) |  | (1.7) |  |
Net cash used in discontinued operations | — |  | — |  | — |  |
Net cash used in financing activities | $ | (24.0) |  | $ | (22.3) |  | $ | (1.7) |  |

The increase in cash used in financing activities in 2025 from 2024 was largely due to higher dividend payments in 2025. 2024 had higher new debt issuance proceeds and higher repayments of both long-term debt and short-term borrowings largely offsetting, resulting in an immaterial net change.
Capital expenditures
Capital expenditures for the first nine months of 2025 and 2024 were $379.5 million and $377.3 million, respectively. Capital expenditures at the Company's business segments are estimated to be approximately $531.7 million for 2025, which is comparable to what was previously reported in the 2024 Annual Report. Capital expenditure estimates have been updated to accommodate project timeline and scope changes made thus far in 2025.
Utility investments in the Company's estimated capital expenditures for 2025 include construction of electric transmission lines and substations, as well as natural gas delivery infrastructure, to serve a customer base that is expected to continue growing at 1 percent to 2 percent annually over the next five years, construction of JETx, power generation projects, and replacement and modernization of existing electric and natural gas utility infrastructure to ensure continued safe and reliable service to customers. Estimated capital expenditures at the utility includes the $29.4 million progress payment associated with Badger Wind Farm. The final payment of Badger Wind Farm would be incremental to the outlined capital program. At the pipeline business, the Company will focus on system growth to expand natural gas transmission capacity. For more information on the Company's growth projects, see Business Segment Financial and Operating Data. Other estimated capital expenditures include those for system upgrades, routine replacements, service extensions, RNG infrastructure projects, routine equipment maintenance and replacements, land and building improvements, pipeline and natural gas storage projects, transmission opportunities, environmental upgrades, and other growth opportunities.
The Company continues to evaluate potential future acquisitions and other growth opportunities that would be incremental to the outlined capital program; however, they are dependent upon the availability of economic opportunities and, as a result, capital expenditures may vary significantly from the estimate previously discussed. The Company continuously monitors its capital expenditures for project delays and changes in economic viability and adjusts as necessary. It is anticipated that all of the funds required for capital expenditures for 2025 will be funded by various sources, including internally generated funds; credit facilities and commercial paper of the Company and its subsidiaries, as described later; and issuance of debt and equity securities if necessary.
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Capital resources
The Company requires significant cash to support and grow its businesses. The primary sources of cash other than cash generated from operating activities are cash from revolving credit facilities, the issuance of long-term debt and the sale of equity securities.
Debt resources
Certain debt instruments of the Company and its subsidiaries contain restrictive and financial covenants and cross-default provisions. In order to borrow under the respective debt instruments, the Company and its subsidiaries must be in compliance with the applicable covenants and certain other conditions, all of which the Company and its subsidiaries, as applicable, were in compliance with at September 30, 2025, except as otherwise noted below. In the event the Company and its subsidiaries do not comply with the applicable covenants and other conditions, alternative sources of funding may need to be pursued. As of September 30, 2025, the Company had investment grade credit ratings at all entities issuing debt. For more information on the covenants, certain other conditions and cross-default provisions, see Part II, Item 6 in this document and Part II, Item 8 in the 2024 Annual Report.
The following table summarizes the outstanding revolving credit facilities of the Company and its subsidiaries at September 30, 2025:

Company |  | Facility |  | Facility Limit |  | Amount Outstanding |  | Letters of Credit |  | Expiration Date |
|  |  |  | (In millions) |  |  |  |  |
Montana-Dakota Utilities Co. |  | Commercial paper/Revolving credit agreement | (a) | $ | 200.0 |  |  | $ | 132.7 |  |  | $ | — |  |  | 10/18/28 |
Cascade Natural Gas Corporation |  | Revolving credit agreement |  | $ | 175.0 |  | (b) | $ | 91.4 |  |  | $ | 2.2 |  | (c) | 6/20/29 |
Intermountain Gas Company |  | Revolving credit agreement |  | $ | 175.0 |  | (b) | $ | 72.0 |  |  | $ | — |  |  | 6/20/29 |
MDU Resources Group, Inc. |  | Revolving credit agreement |  | $ | 200.0 |  | (d) | $ | 20.0 |  |  | $ | 1.0 |  | (c) | 5/31/28 |

(a)The commercial paper program is supported by a revolving credit agreement with various banks (provisions allow for increased borrowings, at the option of Montana-Dakota on stated conditions, up to a maximum of $250.0 million). At September 30, 2025, there were no amounts outstanding under the revolving credit agreement. (b)Certain provisions allow for increased borrowings, up to a maximum of $225.0 million. (c)Outstanding letter(s) of credit reduce the amount available under the credit agreement. (d)Certain provisions allow for increased borrowings, up to a maximum of $250.0 million.

The Montana-Dakota commercial paper program is supported by a revolving credit agreement. While the amount of commercial paper outstanding does not reduce available capacity under the revolving credit agreement, Montana-Dakota does not issue commercial paper in an aggregate amount exceeding the available capacity under the credit agreement. The commercial paper and revolving credit agreement borrowings may vary during the period, largely the result of fluctuations in working capital requirements due to the seasonality of certain operations of Montana-Dakota.
Total equity as a percent of total capitalization was 54 percent, 56 percent and 54 percent at September 30, 2025 and 2024 and December 31, 2024, respectively. This ratio is calculated as the Company's total equity, divided by the Company's total capital. Total capital is the Company's total debt, including debt in discontinued operations, short-term borrowings and long-term debt due within 12 months, plus total equity. Management believes this ratio is an indicator of how the Company is financing its operations, as well as its financial strength.
Intermountain On July 15, 2025, Intermountain entered into a NPA to issue a total of $50.0 million of senior notes, with a maturity date of July 15, 2055, at an interest rate of 6.39 percent. On July 15, 2025, Intermountain issued $25.0 million in senior notes under the NPA with the remaining $25.0 million expected to be issued on November 14, 2025. As of September 30, 2025, Intermountain was not in compliance with the minimum interest coverage covenant under certain NPAs. This non-compliance triggered cross-default provisions in certain other long-term debt and revolving credit agreements of the Company, Intermountain, and MDU Energy Capital. Subsequent to September 30, 2025, Intermountain and MDU Energy Capital obtained waivers for this non-compliance from the holders of a majority of their respective outstanding notes, and Intermountain and the Company obtained waivers from the lenders of the revolving credit agreements, which collectively cured the impact of any events of default. The Company expects to be in compliance with the minimum interest coverage ratio under the Intermountain NPAs by December 31, 2025.
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Montana-Dakota On October 28, 2025, Montana-Dakota entered into a NPA to issue $250.0 million of senior notes, with maturity dates ranging from October 28, 2035 to February 2, 2056, at a weighted average interest rate of 5.96 percent. On October 28, 2025, Montana-Dakota issued $150.0 million in senior notes under the NPA with the remaining $100.0 million expected to be issued on February 2, 2026. The agreement contains customary covenants and provisions, including a covenant of Montana-Dakota not to permit, at any time, the ratio of debt to total capitalization to be greater than 65 percent. Other covenants include a minimum interest coverage ratio and restrictions on the sale of certain assets.
Equity Resources
On August 7, 2025, the Company entered into an EDA pursuant to which it may issue, offer, and sell, from time to time, up to an aggregate gross sales price of $400.0 million of shares of its common stock through an ATM offering program, which includes the ability to enter into FSAs. Since the establishment of the ATM offering program, the Company did not issue common stock pursuant to the EDA nor enter into any FSAs.
Material cash requirements
There were no material changes in the Company's remaining contractual obligations related to estimated interest payments, asset retirement obligations and uncertain tax positions for 2025 from those reported in the 2024 Annual Report except for decreases in purchase commitments due to an anticipated decrease in electric supply contracts at the Company's electric segment. For more information on the Company's contractual obligations on long-term debt and operating leases, see Part II, Item 7 in the 2024 Annual Report. For more information on the Company's purchase commitments, see Note 18.
Material short-term cash requirements of the Company include repayment of outstanding borrowings and interest payments on those agreements, payments on operating lease agreements, payment of obligations on purchase commitments and asset retirement obligations.
Material long-term cash requirements of the Company include repayment of outstanding borrowings and interest payments on those agreements, payments on operating lease agreements, payment of obligations on purchase commitments and asset retirement obligations.
Defined benefit pension plans
The Company has noncontributory qualified defined benefit pension plans for certain employees. Various actuarial assumptions are used in calculating the benefit expense (income) and liability (asset) related to these plans, as such costs of providing these benefits bear the risk of changes as they are dependent upon assumptions of future conditions.
There were no material changes to the Company's noncontributory qualified defined benefit pension plans from those reported in the 2024 Annual Report other than the Company now expects to contribute approximately $3.4 million to its pension plans in 2025, largely resulting from acceleration of contributions in order to decrease costs. For more information, see Note 16 and Part II, Item 7 in the 2024 Annual Report.
New Accounting Standards
For information regarding new accounting standards, see Note 2, which is incorporated by reference.
Critical Accounting Estimates
The Company's critical accounting estimates include impairment testing of goodwill; regulatory assets expected to be recovered in rates charged to customers; actuarially determined pension and other postretirement benefit costs; and income taxes. There were no material changes in the Company's critical accounting estimates from those reported in the 2024 Annual Report, except for the estimate related to construction contract revenue recognition, which is no longer a critical accounting estimate subsequent to the separation of Everus in 2024. For more information on critical accounting estimates, see Part II, Item 7 in the 2024 Annual Report.
Item 3. Quantitative and Qualitative Disclosures About Market Risk
The Company uses fixed and variable rate debt to partially finance operations and capital investments which exposes the Company to market risk related to changes in interest rates. Higher interest rates have resulted in and will likely continue to result in higher borrowing costs on new debt and existing variable interest rate debt.
As of September 30, 2025, approximately 13.4 percent of the outstanding debt recorded on the balance sheet consisted of variable interest rate facilities (which uses SOFR as the benchmark rate). Based on the balances outstanding for these borrowings as of September 30, 2025, an increase of 1 percent in the interest rate on the Company's outstanding variable interest rate facilities would result in an estimated $3.2 million pre-tax annual increase in interest expense over the next twelve months.
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Item 4. Controls and Procedures
Evaluation of disclosure controls and procedures
The term "disclosure controls and procedures" is defined in Rules 13a-15(e) and 15d-15(e) under the Exchange Act. The Company's disclosure controls and other procedures are designed to provide reasonable assurance that information required to be disclosed in the reports that the Company files or submits under the Exchange Act is recorded, processed, summarized and reported within the time periods specified in the SEC's rules and forms. The Company's disclosure controls and other procedures are designed to provide reasonable assurance that information required to be disclosed is accumulated and communicated to management, including the Company's chief executive officer and chief financial officer, to allow timely decisions regarding required disclosure. The Company's management, with the participation of the Company's chief executive officer and chief financial officer, has evaluated the effectiveness of the Company's disclosure controls and other procedures as of the end of the period covered by this report. Based upon that evaluation, the chief executive officer and the chief financial officer have concluded that, as of the end of the period covered by this report, such controls and procedures were effective at a reasonable assurance level.
Changes in internal controls
No change in the Company's internal control over financial reporting (as defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act) occurred during the three months ended September 30, 2025, that has materially affected, or is reasonably likely to materially affect, the Company's internal control over financial reporting.
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Part II -- Other Information
Item 1. Legal Proceedings
There were no material changes to the Company's legal proceedings in Part 1, Item 3 - Legal Proceedings in the 2024 Annual Report.
Item 1A. Risk Factors
Please refer to the Company's risk factors that are disclosed in Part I, Item 1A. Risk Factors in the 2024 Annual Report that could be materially harmful to the Company's business, prospects, financial condition or financial results if they occur. At September 30, 2025, there were no material changes to the Company's risk factors provided in Part I, Item 1A. Risk Factors in the 2024 Annual Report other than as set forth below.
Tariffs and changes in trade policy could negatively impact the Company's operations.
The United States government has recently implemented changes to trade policy and introduced tariffs on a range of products from certain countries, in addition to applying baseline tariffs on imports from most countries. These actions have created uncertainty in global markets and have increased and may continue to increase the cost of raw materials, commodities, supplies and equipment purchased by the Company. Additionally, the tariff and trade policy changes could cause supply chain disruptions and delays in sourcing materials and equipment which could delay large capital projects and negatively impact the Company’s financial condition and results of operations. If the Company's regulators do not determine the increased costs are prudent, or otherwise disallow certain costs, it could affect the Company’s ability to recover the cost increases through rates or on a timely basis which could adversely affect the Company's financial condition and results of operations.
Item 2. Unregistered Sales of Equity Securities and Use of Proceeds
The following table includes information with respect to the Company's purchase of equity securities:

ISSUER PURCHASES OF EQUITY SECURITIES
Period | Total Number of Shares (or Units) Purchased (1) | Average Price Paid per Share (or Unit) | Total Number of Shares (or Units) Purchased as Part of Publicly Announced Plans or Programs (2) | Maximum Number (or Approximate Dollar Value) of Shares (or Units) that May Yet Be Purchased Under the Plans or Programs (2)
July 1 through July 31, 2025 | — |  | $ | — |  | — |  | — |
August 1 through August 31, 2025 | — |  | $ | — |  | — |  | — |
September 1 through September 30, 2025 | 1,723 |  | $ | 17.84 |  | — |  | — |
Total | 1,723 |  | $ | 17.84 |  | — |  | — |

(1) Represents shares of common stock purchased on the open market for the Company's non-employee directors who elected to receive additional shares of common stock in lieu of a portion of their cash retainer. (2) Not applicable. The Company does not currently have in place any publicly announced plans or programs to repurchase equity securities.

Item 5. Other Information
During the three months ended September 30, 2025, no director or officer of the Company adopted or terminated a “Rule 10b5-1 trading arrangement” or “non-Rule 10b5-1 trading arrangement,” as each term is defined in Item 408(a) of Regulation S-K.
Item 6. Exhibits
See the index to exhibits immediately preceding the signature page to this report.
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Index

Exhibits Index
|  |  | Incorporated by Reference
Exhibit Number | Exhibit Description | Filed Herewith | Form | Period Ended | Exhibit | Filing Date | File Number
3(a) | Amended and Restated Certificate of Incorporation of MDU Resources Group, Inc. |  | 8-K |  | 3.2 | 5/8/19 | 1-03480
3(b) | Bylaws of MDU Resources Group, Inc. |  | 8-K |  | 3.1 | 2/14/25 | 1-03480
**4(a) | Intermountain Gas Comp any Note Purchase Agreement, dated July 15, 20 25 | X |  |  |  |  |
31(a) | Certification of Chief Executive Officer filed pursuant to Section 302 of the Sarbanes-Oxley Act of 2002 | X |  |  |  |  |
31(b) | Certification of Chief Financial Officer filed pursuant to Section 302 of the Sarbanes-Oxley Act of 2002 | X |  |  |  |  |
*32 | Certification of Chief Executive Officer and Chief Financial Officer furnished pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002 | X |  |  |  |  |
101.INS | XBRL Instance Document - the instance document does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document |  |  |  |  |  |
101.SCH | XBRL Taxonomy Extension Schema Document |  |  |  |  |  |
101.CAL | XBRL Taxonomy Extension Calculation Linkbase Document |  |  |  |  |  |
101.DEF | XBRL Taxonomy Extension Definition Linkbase Document |  |  |  |  |  |
101.LAB | XBRL Taxonomy Extension Label Linkbase Document |  |  |  |  |  |
101.PRE | XBRL Taxonomy Extension Presentation Linkbase Document |  |  |  |  |  |
104 | Cover Page Interactive Data File (formatted as Inline XBRL and contained in Exhibit 101) |  |  |  |  |  |

*Furnished Herewith
**Schedules and exhibits to this agreement have been omitted pursuant to Item 601(a)(5) of Regulation S-K. A copy of any omitted schedule and/or exhibit will be furnished as a supplement to the SEC upon request.

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

|  | MDU RESOURCES GROUP, INC.
DATE: | November 10, 2025 | BY: | /s/ Jason L. Vollmer
|  |  | Jason L. Vollmer
|  |  | Chief Financial Officer
|  | BY: | /s/ Stephanie A. Sievert
|  |  | Stephanie A. Sievert
|  |  | Chief Accounting and Regulatory Affairs Officer

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