Form 10-Q BASIN ELECTRIC POWER For: Mar 31

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Basin Electric Power Cooperative (Basin Electric) is an electric generation and transmission cooperative corporation, organized and existing under the laws of the State of North Dakota. It serves member electric service needs in a nine-state region of North Dakota, South Dakota, Montana, Wyoming, New Mexico, Colorado, Nebraska, Minnesota and Iowa. Basin Electric’s power supply resources are composed of its own generating facilities and contractual power purchase arrangements. Basin Electric owns and operates transmission assets, some of which are a part of regional transmission organizations.

The rates charged to its members for electric service are established by Basin Electric’s Board of Directors with changes in rates subject to acceptance by the United States Department of Agriculture Rural Utilities Service (RUS).

Basin Electric has three wholly owned for-profit subsidiaries, Dakota Gasification Company (Dakota Gas), Dakota Coal Company (Dakota Coal), and Nemadji River Generation (NRG). Basin Electric also has one wholly owned not-for-profit subsidiary, Basin Cooperative Services (BCS). Dakota Gas has a wholly owned for-profit subsidiary, Souris Valley Pipeline Limited (SVPL). Dakota Coal has a wholly owned for-profit subsidiary, Montana Limestone Company (MLC). Dakota Gas owns and operates the Great Plains Synfuels Plant (Synfuels Plant) which converts lignite coal into pipeline-quality synthetic gas and produces a number of other products including anhydrous ammonia, urea, diesel exhaust fluid (DEF), carbon dioxide (CO2), tar oil and chemical products. The Synfuels Plant is located adjacent to Basin Electric’s Antelope Valley Station (AVS) electric generating plant. These plants share certain facilities, and coal and water supplies. Dakota Gas supplies various Basin Electric gas generating stations and AVS with synthetic gas. SVPL owns and operates a CO2 pipeline in Saskatchewan, Canada. Dakota Coal purchases lignite coal from the Freedom Mine, a coal mine in North Dakota that is owned and operated by The Coteau Properties Company (Coteau), a wholly owned subsidiary of The North American Coal Corporation (NACoal). NACoal is a wholly owned subsidiary of NACCO Industries, Inc. (NACCO). Coteau is a variable interest entity (VIE) of Dakota Coal. Pursuant to the coal purchase agreement, Dakota Coal is obligated to provide financing for and has certain rights with respect to the operation of the coal mine. The lignite coal is used in Basin Electric’s Leland Olds Station (LOS), AVS, and Dakota Gas’s Synfuels Plant. Dakota Coal coordinates procurement and rail delivery of Powder River Basin coal to the Laramie River Station (LRS) and the Dry Fork Station (DFS). Dakota Coal also owns a lime plant that sells lime to AVS, the Laramie River Station (LRS) and others. MLC operates a limestone quarry and owns and operates a fine grind plant, both in Montana, and sells limestone to Dakota Coal’s lime plant, LOS and others. BCS provides certain nonutility property management services to Basin Electric. Basin Electric is a 42.27% owner of the Missouri Basin Power Project (MBPP) and acts as the operating agent for the 1,700 megawatt LRS generating plant in Wyoming, associated transmission facilities and the Grayrocks Dam and Reservoir. Basin Electric’s ownership in MBPP is accounted for using proportionate consolidation consistent with accounting for jointly owned utility property. NRG was a 30 percent owner in the Nemadji Trail Energy Center (NTEC) project, which was a proposed 600 megawatt combined cycle generating plant in Wisconsin. In January 2026, NRG exited the NTEC project and the NRG subsidiary is expected to be fully dissolved by the end of 2026.

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PRINCIPLES OF CONSOLIDATION–The consolidated financial statements include the accounts of Basin Electric, its wholly owned subsidiaries and its VIE’s, Coteau and DCS. DCS is considered a VIE for which Dakota Gas is the primary beneficiary. All intercompany investments, debt, and receivable and payable accounts have been eliminated in consolidation. Charges from BCS, Dakota Gas, Dakota Coal, MLC and Coteau to Basin Electric and charges from Basin Electric to BCS, Dakota Gas, Dakota Coal, MLC and Coteau are not eliminated as Basin Electric includes the results of these activities in the determination of rates charged to its members (Note 16).

N-7 LLC (N-7) is a Delaware limited liability company formed by OCI Iowa, Inc. (OCI) and Dakota Gas on May 18, 2018. N-7 was formed to market OCI’s, Dakota Gas’s and other companies’ fertilizer and DEF production. N-7 is considered a VIE of Dakota Gas for which Dakota Gas is not the primary beneficiary and, therefore, Dakota Gas is not required to consolidate N-7. However, Dakota Gas has the ability to exercise significant influence over N-7. Therefore, Dakota Gas’s share of N-7 net income is recorded in the consolidated financial statements using the equity method of accounting. The investment in N-7 is included in other investments on the consolidated balance sheets and Dakota Gas’ share of N-7 net income is presented in other and tax credits income in the consolidated statements of operations.

In 2024, Dakota Gas and OCI agreed to dissolve N-7 with final dissolution to be completed in 2026. Basin Electric does not anticipate this to have a material impact on the consolidated financial statements and disclosures.

USE OF ESTIMATES–The preparation of consolidated financial statements in conformity with accounting principles generally accepted in the United States of America (GAAP) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenue and expenses during the reporting period. Estimates are used for items such as present value of lease assets and lease liabilities, plant depreciable lives, actuarially determined benefit costs, valuation of derivatives, asset retirement obligations, present value of expected tax credits, cash flows used in asset impairment evaluations and income tax expense or benefits. Ultimate results could differ from those estimates.

INTERIM FINANCIAL INFORMATION–Basin Electric’s consolidated interim financial statements are unaudited, and reflect all adjustments management considers necessary (consisting of normal recurring accruals) for a fair presentation. The Financial Statements included herein have been prepared pursuant to the rules and regulations of the U.S. Securities and Exchange Commission (SEC). Certain information and footnote disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations; however, we believe that the condensed disclosures provided are adequate to make the information presented not misleading. Basin Electric’s operating results are affected by various factors including sales to members which may vary with weather conditions, the availability and market for sales of surplus power, actions of the Basin Electric board of directors in their role as regulator, general business conditions, the demand for non-utility products and services produced by Dakota Gas, Dakota Coal and Basin Electric’s other subsidiary companies and availability of substitute products in the market, and operating costs which vary based on plant outages, labor conditions and other costs of production. Accordingly, Basin Electric’s operating results for the three-month periods ended March 31, 2026 and 2025 are not necessarily an appropriate base from which to project annual results.

The consolidated interim financial statements should be read in conjunction with the audited consolidated financial statements and notes included in Basin Electric’s final prospectus filed with the SEC pursuant to Rule 424(b) under the Securities Act of 1933, as amended, on May 6, 2026 (the Prospectus). There have been no changes to Basin Electric’s significant accounting policies described in the Prospectus that have had a material impact on Basin Electric’s consolidated interim financial statements and related notes.

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RECENTLY ISSUED ACCOUNTING STANDARD UPDATES (ASU) NOT YET ADOPTED

ASU No. 2024-03, Income Statement-Reporting Comprehensive Income-Expense Disaggregation Disclosures: Disaggregation of Income Statement Expenses – In November 2024, the FASB issued new guidance to improve disclosures about a public business entity’s expenses that will require additional detail for certain categories of income statement expenses. The new guidance will be effective for Basin Electric for annual reporting periods beginning after December 15, 2026, and interim reporting periods beginning after December 15, 2027. Early adoption is permitted and the new guidance is to be applied either on a prospective or retrospective basis. Management is currently evaluating the impact of adoption of this new guidance on the financial statements and disclosures.

ASU No. 2025-06, Intangibles-Goodwill and Other-Internal-Use Software: Targeted Improvements to the Accounting for Internal-Use Software – In September 2025, the FASB issued new guidance to modernize existing older guidance regarding capitalization and recognition to reflect the software development approaches currently being utilized. The new guidance will be effective for Basin Electric for annual reporting periods beginning after December 15, 2027, and interim reporting periods within those annual reporting periods. Early adoption is permitted and the new guidance is to be applied using one of the three prescribed approaches. Management is currently evaluating the impact of adoption of this new guidance on the financial statements and disclosures.

ASU No. 2025-09, Derivatives and Hedging: Hedge Accounting Improvements – In November 2025, the FASB issued new guidance in an effort to better reflect an entity's risk management activities in the financial statements. The update makes targeted improvements by addressing five specific matters that arose from the implementation of previous ASU 2017-12, Derivatives and Hedging: Targeted Improvements for Accounting for Hedging Activities and the effects of LIBOR cessation. The new guidance will be effective for Basin Electric for annual reporting periods beginning after December 15, 2026, and interim reporting periods within those annual reporting periods. Early adoption is permitted and the new guidance is to be applied on a prospective basis, although an entity may elect to adopt the guidance for hedging relationships that exist as of the date of adoption. Management is currently evaluating the impact of adoption of this new guidance on the financial statements and disclosures.

ASU No. 2025-10, Government Grants: Accounting for Government Grants Received by Business Entities – In December 2025, the FASB issued new guidance to improve GAAP by establishing authoritative guidance on the accounting for government grants received by business entities. Previously, GAAP did not provide specific guidance about the recognition, measurement, and presentation of a grant received by a business entity from a government, and due to this absence of specific guidance, Basin Electric like many other business entities, utilized the guidance contained in IAS 20, Accounting for Government Grants and Disclosure of Government Assistance. The new guidance will be effective for Basin Electric for annual reporting periods beginning after December 15, 2028, and interim reporting periods within those annual reporting periods. Early adoption is permitted and the new guidance is to be applied using one of the three prescribed approaches. Management is currently evaluating the impact of adoption of this new guidance on the financial statements and disclosures.

Cash, cash equivalents, and restricted and designated cash and cash equivalents reported within the

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consolidated balance sheets and included in the consolidated statement of cash flows are as follows:

			March 31, 2026						December 31, 2025
			(In thousands)
Cash and cash equivalents			$	622,221					$	685,570
Restricted and designated cash and equivalents:
MBPP operating funds			31,190						29,923
Deferred revenue			272,000						272,000
			303,190						301,923
Total cash, cash equivalents and restricted and designated cash and equivalents included in the consolidated statements of cash flows			$	925,411					$	987,493

Restricted and designated investments reported within the consolidated balance sheets are as follows:

			March 31, 2026						December 31, 2025
			(In thousands)
Restricted and designated investments:
Funds held in trust for an asset retirement obligation by Bank of Montreal as trustee for SVPL			5,487						5,244
Asset retirement obligations			54,620						56,118
			$	60,107					$	61,362

Restricted cash and investments include funds held by a financial institution, as trustee. Designated cash and investments includes amounts designated by the Basin Electric Board of Directors.

INVENTORIES–Inventories were as follows:

			March 31, 2026						December 31, 2025
			(In thousands)
Materials and supplies			$	259,968					$	245,857
Coal and fuel oil			61,232						62,238
Urea			20,891						18,786
Ammonia			14,655						9,233
Ammonium sulfate			7,952						5,081
Lime and limestone			7,886						8,484
Natural gas held in storage			1,688						2,055
Other			6,124						7,078
			$	380,396					$	358,812

COLLATERAL-Certain derivative instruments and certain agreements of Basin Electric and Dakota Gas contain contract provisions that require collateral to be posted if the credit ratings of Basin Electric fall below certain levels or if the counterparty exposure to Basin Electric or Dakota Gas exceeds a certain level.

Collateral posted (received) is related to derivative assets and liabilities and agreements that contain

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credit-related contingent features and is in the consolidated balance sheets as follows:

			March 31, 2026						December 31, 2025
			(In thousands)
Other investments			$	51,215					$	47,575
Prepayments and other current assets			26,350						3,350
Taxes and other current liabilities			(5,434)						(1,954)
			$	72,131					$	48,971

Investments in equity securities and available-for-sale debt securities are included in mine related assets, restricted and designated investments and other investments on the consolidated balance sheets. The cost, unrealized holding gains and losses, and fair value of equity and debt securities that do not have an allowance for credit losses were as follows as of March 31, 2026:

									Gross Unrealized Holding												Fair Value
			Cost						Gains						Losses
			(In thousands)
Available-for-sale debt securities:
Corporate and government bonds			$	1,958					$	44					$	—					$	2,002
Equity securities:
Equities and equity funds			43,347						79,899						—						123,246
Bond market funds			79,293						—						(6,239)						73,054
			122,640						79,899						(6,239)						196,300
Other			208						—						—						208
			$	124,806					$	79,943					$	(6,239)					$	198,510

The cost, unrealized holding gains and losses, and fair value of equity and debt securities that do not have an allowance for credit losses were as follows as of December 31, 2025:

									Gross Unrealized Holding												Fair Value
			Cost						Gains						Losses
			(In thousands)
Available-for-sale debt securities:
Corporate and government bonds			$	1,947					$	24					$	—					$	1,971
Equity securities:
Equities and equity funds			42,147						86,512						—						128,659
Bond market funds			78,577						—						(5,573)						73,004
			120,724						86,512						(5,573)						201,663
Other			88						—						—						88
			$	122,759					$	86,536					$	(5,573)					$	203,722

For the three months ended March 31, 2026, there were no sales proceeds on debt securities classified as available-for-sale. For the three months ended March 31, 2025, sales proceeds on debt securities classified as available-for-sale were $17.3 million. The cost of securities sold is based on the specific identification method. The realized losses for the three months ended March 31, 2025 were immaterial.

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The fair value of available-for-sale debt securities by contracted maturity date as of March 31, 2026 was as follows:

			March 31, 2026
			(In thousands)
Due through one year			$	461
Due after one year through five years			729
Due after five years			812
			$	2,002

Held-to-maturity debt securities have contracted maturity dates of one year or less and are included in cash and cash equivalents, restricted and designated cash and cash equivalents and short-term investments on the consolidated balance sheets. The amortized cost of held-to-maturity debt securities as of March 31, 2026 and December 31, 2025, was as follows:

			March 31, 2026						December 31, 2025
			(In thousands)
Corporate commercial paper			$	17,650					$	38,030
Money market funds			689,108						745,170
Treasuries			209,292						199,300
			$	916,050					$	982,500

Included in other investments on the consolidated balance sheets is the cash surrender value of life insurance policies of $1.7 million and $1.6 million, as of March 31, 2026 and December 31, 2025, respectively.

The MBPP provides financing to Western Fuels Association (Western Fuels) and Western Fuels-Wyoming, Inc. (WFW), a wholly owned subsidiary of Western Fuels, for mine development costs associated with coal deliveries to LRS. Basin Electric provides financing to Western Fuels and WFW for mine development costs associated with coal deliveries to DFS.

Notes receivable from WFW of $20.3 million and $20.8 million as of March 31, 2026 and December 31, 2025, respectively, are included in other investments, investments in associated companies and receivables, net on the consolidated balance sheets. Maturities range from July 2026 through May 2043, and the weighted average interest rate is 5.53 percent. The estimated fair value of these notes receivable as of March 31, 2026 and December 31, 2025 was $20.4 million and $21.0 million, respectively, based on the future cash flows discounted using the yield on a treasury note with a similar maturity.

Normal operations expose Basin Electric to risks associated with changes in the market price of certain commodities. Basin Electric entered into derivative financial instruments for the purpose of mitigating the risks associated with market price volatility of natural gas, tar oil, electricity and diesel. Any changes in cash flows from the underlying purchases and sales that are indexed to certain prices are offset by corresponding changes in the cash flows from the derivatives. As directed by a Basin Electric Board of Director’s policy (Board Policy) to monitor risk and establish an internal control framework, Basin Electric maintains a Risk Management Steering Committee (RMSC) that is governed by a Commodity Risk Management Manual (Manual). The Board Policy prohibits speculation and the Manual has been adopted by the RMSC. In offsetting market risk, Basin Electric is exposed to other forms of incremental risk such as credit or liquidity risk.

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The following table presents the outstanding hedged forecasted transactions as of March 31, 2026:

Hedged Transaction

Term

Contracted Monthly Volumes of Forecasted Transactions

Price

Natural gas purchases

Through December 2033

20% to 62%

$2.79 - $6.51 per dekatherm

Tar oil sales

Through December 2027

23% to 90%

$52.00 - $93.80 per barrel

Electricity purchases

Through December 2027

24% to 90%

$30.50 - $58.60 per MWh

Diesel purchases

Through January 2029

9% to 80%

$2.05 - $2.44 per gallon

Basin Electric is also exposed to interest rate risk. To mitigate this risk, Basin Electric entered into various interest rate swaps to reduce the impact of changes in interest rates on certain variable rate long-term bonds and projected future bond issuances. The total notional amount of outstanding swap agreements as of March 31, 2026, was $325.0 million with due dates ranging from 2032 through 2058 at a weighted average interest rate of 5.10 percent.

The fair value and classification of the asset and liability portion of the derivative instruments in the consolidated balance sheets is as follows:

						March 31, 2026												December 31, 2025
Balance Sheet Location						Fair Value of Asset Derivatives						Fair Value of Liability Derivatives						Fair Value of Asset Derivatives						Fair Value of Liability Derivatives
						(In thousands)
Derivatives designated as cash flow hedges:
Commodity derivatives:
Prepayments and other current assets						$	5,031					$	—					$	5,312					$	—
Other investments						1,858						—						1,684						—
Other current liabilities						—						(8,104)						—						(1,319)
Other noncurrent liabilities						—						(1,693)						—						(671)
Total derivatives designated as cash flow hedges						6,889						(9,797)						6,996						(1,990)
Derivatives not designated as cash flow hedges:
Commodity derivatives:
Prepayments and other current assets						12,367						—						34,673						—
Other investments						—						—						1,211						—
Other current liabilities						—						(10,895)						—						(14,763)
Other noncurrent liabilities						—						(13,072)						—						(14,687)
Interest rate derivatives:
Other noncurrent liabilities						—						(19,689)						—						(22,031)
Total derivatives not designated as cash flow hedges						12,367						(43,656)						35,884						(51,481)
						$	19,256					$	(53,453)					$	42,880					$	(53,471)

Under ASC 980, Basin Electric’s Board of Directors defers changes in the fair value of certain derivative instruments as regulatory assets or liabilities. Current settlements of derivatives, including interest rate swaps and commodity derivatives, resulted in (credits) charges to the consolidated statements of operations for the three months ended March 31, 2026 and 2025 of $(14.3) million and $8.3 million, respectively, which are reclassified from regulatory assets and liabilities.

The change in fair value of derivatives deferred as a regulatory item for the three months ended March 31, 2026 and the year ended December 31, 2025 resulted in net deferred (gains) losses of $(9.9) million and $21.7 million, respectively.

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For derivative instruments that are designated and qualify as a cash flow hedge under ASC 815, the gain or loss on the derivative instrument is reported as a component of other comprehensive income (loss) and reclassified into net earnings in the same period or periods during which the hedged transaction affects net margin and earnings and is presented in the same line item on the consolidated statements of operations as the net earnings effect of the hedged item.

The following table summarizes Dakota Gas and Dakota Coal gains and losses and financial statement classification of the derivatives designated as cash flow hedges as of March 31, 2026. This does not reflect the expected gains or losses arising from the underlying physical transactions; therefore it is not indicative of the economic gross profit or loss realized when the underlying physical and financial transactions were settled.

			Location of Loss Recognized in Net (Gain) Loss on Cash Flow Hedging Relationships
			March 31, 2026
			Other Operating Revenues						Cost of Products Sold
			(In thousands)
Total amounts of income and expense line items presented on the consolidated statements of operations in which the effects of cash flow hedges are recorded			$	240,425					$	131,746
Loss on cash flow hedges:
Commodity derivatives:
Amount reclassified from accumulated other comprehensive income into net margins and earnings			$	(760)					$	(28)

The following table summarizes Dakota Gas and Dakota Coal gains and losses and financial statement classification of the derivatives designated as cash flow hedges as of March 31, 2025. This does not reflect the expected gains or losses arising from the underlying physical transactions; therefore it is not indicative of the economic gross profit or loss realized when the underlying physical and financial transactions were settled.

			Location of Gain (Loss) Recognized in Net (Gain) Loss on Cash Flow Hedging Relationships
			March 31, 2025
			Other Operating Revenues						Cost of Products Sold
			(In thousands)
Total amounts of income and expense line items presented on the consolidated statements of operations in which the effects of cash flow hedges are recorded			$	222,934					$	123,734
Gain (loss) on cash flow hedges:
Commodity derivatives:
Amount reclassified from accumulated other comprehensive income into net margins and earnings			$	554					$	(73)

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The following table summarizes Dakota Gas and Dakota Coal gains and losses and financial statement classification of the derivatives designated as cash flow hedges for the three months ended March 31, 2026 and 2025.

			March 31, 2026						March 31, 2025
			(In thousands)
Decrease in fair value of commodity derivatives			$	(8,703)					$	(1,486)
Recognition of losses (gains) in earnings due to settlements on commodity derivatives			788						(481)
Total other comprehensive loss from hedging			$	(7,915)					$	(1,967)

Based on March 31, 2026 prices, a $3.1 million loss would be realized, reported in pre-tax earnings and reclassified from accumulated other comprehensive income during the next 12 months. As market prices fluctuate, estimated and actual realized gains or losses will change during future periods.

There are certain commodity derivative financial instruments that do not meet the criteria for hedge accounting under ASC 815 when using the critical terms match effectiveness assessment. For those derivatives, gains or losses are recorded in the consolidated statements of operations. The following table summarizes the impact of commodity derivatives that do not meet the criteria. This does not reflect the expected gains or losses arising from the underlying physical transactions; therefore it is not indicative of the economic gross profit or loss realized when the underlying physical and financial transactions were settled.

						March 31, 2026						March 31, 2025
Location of Gain on Derivatives Recognized in Net Margin and Earnings						Recognized Gain						Recognized Gain
						(In thousands)
Derivatives not designated as cash flow hedges:
Commodity derivatives:
Other operating revenues						$	19					$	86
Total						$	19					86

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Regulatory assets and liabilities were as follows at:

			Remaining Recovery Period						March 31, 2026						December 31, 2025
									(In thousands)
Regulatory assets:
Deferred income taxes			Over Plant lives						$	164,726					$	160,754
Refinancing fees			Up to 24 years						78,579						80,122
Unrealized loss on interest rate swaps			Up to 6 years						20,263						21,066
Unrealized loss on commodity derivatives			Up to 8 years						19,190						28,239
Other			Up to 49 years						21,068						21,192
									303,826						311,373
Regulatory liabilities:
Deferred revenue									(272,000)						(272,000)
Unrealized gain on equity investments									(16,436)						(18,489)
Post-retirement medical gain									(21,044)						(21,044)
Other									(22,296)						(24,772)
									(331,776)						(336,305)
Net regulatory liabilities									$	(27,950)					$	(24,932)

If all or a separable portion of Basin Electric’s operations no longer are subject to the provisions of ASC 980, a write-off of net related regulatory assets (liabilities) would be required, unless some form of transition recovery (refund) continues through rates established and collected for Basin Electric’s remaining regulated operations. In addition, Basin Electric would be required to determine any impairment to the carrying costs of deregulated plant and inventory assets.

The following table includes the changes in the balances of the components of accumulated other comprehensive income on the consolidated balance sheets:

			Post Employment  Benefit Plans						Unrealized Gain on Securities						Unrealized Gain (Loss) on Cash Flow Hedges						Total
			(In thousands)
Balance, December 31, 2025			$	9,491					$	16					$	3,956					$	13,463
Other comprehensive income (loss)			(112)						14						(6,252)						(6,350)
Balance, March 31, 2026			$	9,379					$	30					$	(2,296)					$	7,113
Balance, December 31, 2024			$	5,311					$	22					$	(527)					$	4,806
Other comprehensive income (loss)			(168)						183						(1,554)						(1,539)
Balance, March 31, 2025			$	5,143					$	205					$	(2,081)					$	3,267

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Outstanding long-term debt was as follows at:

			Due Date						Weighted Average Interest Rate at March 31, 2026						March 31, 2026						December 31, 2025
															(In thousands)
Basin Electric Power Cooperative
First Mortgage Bonds
2006 Series			June 2041						6.13%						$	200,000					$	200,000
2017 Series			April 2047						4.75%						500,000						500,000
2025 Series			Oct. 2055						5.85%						700,000						700,000
															1,400,000						1,400,000
First Mortgage Obligations
2005 Series			Dec. 2028-May 2030						5.85%						90,000						90,000
2007 Series			Sep. 2042						5.75%						214,711						216,854
2008 Series			Dec. 2028-Dec. 2038						5.92%						413,389						413,389
2009 Series			Oct. 2027-April 2040						5.47%						132,222						132,222
2011 Series			Oct. 2031-Oct. 2049						4.53%						208,080						208,080
2012 Series			Nov. 2044						4.07%						73,949						73,949
2015 Series			June 2027-June 2044						4.50%						1,353,420						1,353,420
2016 CoBank Note			April 2046						4.48%						66,667						68,333
2016 CFC Note			April 2046						3.74%						50,420						51,050
2022 Series			Feb. 2042-Feb. 2062						3.00%						276,810						276,810
2024 CoBank Note			Nov. 2034-May 2035						6.14%						200,000						200,000
2024 Series			Feb. 2029-Feb. 2054						6.22%						344,033						350,525
2007 and 2008 Notes			June 2027-Dec. 2028						5.09%						4,750						4,750
2023 Note			Oct. 2043						5.56%						72,000						72,000
2025 RUS Loan			June 2033						4.33%						538						538
															3,500,989						3,511,920
Equipment Notes			Dec. 2035-Apr. 2036						5.00%						21,446						21,617
2019 Tax-Exempt Bonds			July 2039						3.63%						150,000						150,000
															171,446						171,617
Dakota Coal
Equipment notes			May 2026-July 2036						4.92%						64,345						66,462
Other									Various						12,583						11,806
															76,928						78,268
															5,149,363						5,161,805
Less:
Current portion															(175,854)						(176,019)
Unamortized debt issue costs															(35,059)						(35,447)
Discount payable															(1,067)						(1,075)
Long-term debt, net of current portion															$	4,937,383					$	4,949,264

In October 2025, in connection with the issuance and sale in a private offering of the First Mortgage Bonds, 2025 Series, Basin Electric entered into an exchange and registration rights agreement with the

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representatives of the initial purchasers of the First Mortgage Bonds. Pursuant to such agreement, Basin Electric filed a Registration Statement on Form S-4 with the SEC on April 15, 2026, which was declared effective on May 6, 2026, with respect to an offer to exchange these First Mortgage Bonds for substantially similar First Mortgage Bonds of Basin Electric that are registered under the Securities Act. On June 5, 2026, Basin Electric completed an exchange offer of these First Mortgage Bonds for like principal amounts registered under the Securities Act.

The estimated fair value of debt at March 31, 2026 and December 31, 2025 was $5.0 billion and $5.1 billion, respectively, based on cash flows discounted at interest rates for similar issues or at the current rates offered to Basin Electric for debt of comparable maturities.

NOTES PAYABLE–Basin Electric and Dakota Gas have outstanding revolving credit facilities which are included in Notes payable on the consolidated balance sheets as follows:

Facility						Expiration Date						Facility Limit						Outstanding Amounts as of March 31, 2026
												(In thousands)
Commercial Paper/Revolving Credit Agreement (a)						March 2031						$	100,000					$	100,000
Revolving Credit Agreement (a)						May 2030						1,250,000						-
2025 Term Loan						October 2026						375,000						375,000
Total notes payable												$	1,725,000					$	475,000

_______________

(a)The taxable and tax-exempt commercial paper programs are supported by revolving credit agreements with various banks. Balances reflect commercial paper amounts outstanding. There were no amounts outstanding under the revolving credit agreements.

As of March 31, 2026 and December 31, 2025, the effective interest rate of the outstanding advances was 4.60 percent and 4.74 percent, respectively.

MEMBER INVESTMENT PROGRAM–Basin Electric holds notes related to funds invested by the members under a member investment program. These funds are used by Basin Electric to reduce short-term borrowings. The members receive investment earnings based on market rates, adjusted for administrative costs. The notes held as part of this program were as follows at:

			March 31, 2026						December 31, 2025
			(In thousands)
Long-term debt, net of current portion			$	1,000					$	—
Notes payable – Members			176,988						159,495
			$	177,988					$	159,495

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The following tables disaggregate revenue by major source for the periods presented. The tables also include a reconciliation of the disaggregated revenue by reportable segments. For more information on Basin Electric’s business segments, see Note 14.

			Three Months Ended March 31, 2026
			Electric Utility						Gasification						Coal and Limestone Operations						Elimination of Intersegment						Total
			(In thousands)
Sales of electricity to members			$	600,778					$	—					$	—					$	—					$	600,778
Sales of electricity to non-members			68,804						—						—						—						68,804
Synthetic natural gas			—						42,056						—						—						42,056
Fertilizer and DEF products			—						55,900						—						—						55,900
Other byproducts			—						16,895						—						—						16,895
Lignite coal			—						—						79,062						(30,966)						48,096
Miscellaneous			2,007						344						7,065						—						9,416
Revenue from contracts with customers			671,589						115,195						86,127						(30,966)						841,945
Other revenue			—						(742)						—						—						(742)
Total operating revenue			$	671,589					$	114,453					$	86,127					$	(30,966)					$	841,203

			Three Months Ended March 31, 2025
			Electric Utility						Gasification						Coal and Limestone Operations						Elimination of Intersegment						Total
			(In thousands)
Sales of electricity to members			$	555,678					$	—					$	—					$	—					$	555,678
Sales of electricity to non-members			59,317						—						—						—						59,317
Synthetic natural gas			—						39,888						—						—						39,888
Fertilizer and DEF products			—						51,411						—						—						51,411
Other byproducts			—						18,689						—						—						18,689
Lignite coal			—						—						70,974						(28,604)						42,370
Miscellaneous			2,577						329						6,853						—						9,759
Revenue from contracts with customers			617,572						110,317						77,827						(28,604)						777,112
Other revenue			861						639						—						—						1,500
Total operating revenue			$	618,433					$	110,956					$	77,827					$	(28,604)					$	778,612

OTHER REVENUE–Other revenue includes derivative revenue from hedging activities for synthetic natural gas, tar oil, and electricity sales which is accounted for under ASC 815.

CONTRACT BALANCES–At times, Basin Electric and its subsidiaries will receive payment in advance of performing an obligation under a contract. Unearned revenue, a contract liability, is recognized when this occurs. At March 31, 2026 and December 31, 2025, the unearned revenue balance (included in other current liabilities on the consolidated balance sheets) was $70.1 million and $7.6 million, respectively. There were no contract assets at March 31, 2026 and December 31, 2025. The balance in receivables, net on the consolidated balance sheets represent the unconditional right to consideration from customers.

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POSTRETIREMENT BENEFITS–Eligible employees of Basin Electric, Dakota Gas, and MLC who are retiring may elect to continue medical and dental benefits by paying premiums to continue participating in the current employee plan. Coteau also maintains medical care and life insurance plans which provide benefits to eligible retired employees.

Components of net periodic postretirement benefit expense (income) for the three months ended March 31, 2026 and 2025 were as follows:

			Basin Electric and Subsidiaries												Coteau
			2026						2025						2026						2025
			(In thousands)
Service cost			$	319					$	292					$	3					$	5
Interest cost			258						233						13						16
Amortization of prior service cost			58						58						—						—
Amortization of net actuarial gain			(412)						(459)						(110)						(169)
Net periodic expense (income)			$	223					$	124					$	(94)					$	(148)

Basin Electric, Dakota Gas, and MLC made contributions (withdrawals) of $768,000 and $(163,000) to (from) the postretirement benefit plans during the three months ended March 31, 2026 and 2025, respectively.

DEFINED BENEFIT PLANS

NRECA RS PLAN–Pension benefits for Basin Electric and Dakota Gas employees participating in the pension plan are provided through participation in the National Rural Electric Cooperative Association (NRECA) Retirement Security Plan (RS Plan) which is a defined benefit pension plan qualified under Section 401 and tax-exempt under Section 501(a) of the Internal Revenue code. It is a multiemployer plan under GAAP.

Pension costs charged to expense for the three months ended March 31, 2026 and 2025 were $9.6 million and $9.5 million, respectively.

BCS AND COTEAU PLANS–BCS’s former United Mine Workers of America employees are covered under a defined benefit plan which is funded by BCS. Substantially all of Coteau’s salaried employees hired prior to January 1, 2000, participate in the Coteau Pension Plan (the Plan), a noncontributory defined benefit plan sponsored by NACoal. In October 2025, Coteau terminated the Plan and settled all future obligations by transferring the remaining benefit obligations to a third-party insurance company.

Components of net periodic pension expense (income) for the three months ended March 31, 2026 and 2025 were as follows:

			BCS												Coteau
			2026						2025						2026						2025
			(In thousands)
Interest cost			$	32					$	31					$	—					$	904
Expected return on assets			(34)						(35)						—						(1,027)
Amortization of net actuarial loss			12						16						—						—
Settlements			—						—						45						—
Net periodic expense (income)			$	10					$	12					$	45					$	(123)

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BCS did not make any contributions to the defined benefit plan during the three months ended March 31, 2026. BCS and Coteau did not make any contributions to the defined benefit plans for the three months ended March 31, 2025.

Level 1 inputs utilize observable market data in active markets for identical assets or liabilities. Level 2 inputs consist of observable market data, other than that included in Level 1, that is either directly or indirectly observable. Level 3 inputs consist of unobservable market data which are typically based on an entity’s own assumptions of what a market participant would use in pricing an asset or liability as there is little, if any, related market activity. In instances where the determination of the fair value measurement is based on inputs from different levels of the fair value hierarchy, the level in the fair value hierarchy within which the entire fair value measurement falls is based on the lowest level input that is significant to the fair value measurement in its entirety. Basin Electric’s assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment, and considers factors specific to the asset or liability.

On March 31, 2026 and December 31, 2025, Basin Electric had government obligations, equity securities, bond market funds and corporate bonds included in restricted and designated investments, mine related assets and other investments, recorded at a fair value, using quoted prices in active markets for identical assets as the fair value measurement (Level 1).

Basin Electric recorded derivative financial instruments including commodity contracts and interest rate swaps using significant other observable inputs as the fair value measurement (Level 2). The fair value for commodity contracts is determined by comparing the difference between the net present value of the cash flows for the commodity contracts at their initial price and the current market price. The initial price is quoted in the commodity contract and the current market price is corroborated by observable market data. The fair value for interest rate swap contracts is determined by comparing the difference between the net present value of the cash flows for the swaps at their initial fixed rate and the current market interest rate. The initial fixed rate is quoted in the swap agreement and the current market interest rate is corroborated by observable market data.

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The following table summarizes assets and liabilities measured at fair value on a recurring basis as of March 31, 2026, aggregated by the level in the fair value hierarchy within which those measurements fall:

			Fair Value						Fair Value Measurements Using
									Quoted Prices in Active Markets for Identical Assets and Liabilities (Level 1)						Significant Other Observable Inputs (Level 2)						Significant Unobservable Inputs (Level 3)
			(In thousands)
Assets:
Investments:
Equities and equity funds			$	123,246					$	123,246					$	—					$	—
Corporate and government bonds			2,002						2,002						—						—
Bond market funds			73,054						73,054						—						—
			198,302						198,302						—						—
Commodity derivatives			19,256						—						19,256						—
			$	217,558					$	198,302					$	19,256					$	—
Liabilities:
Interest rate swaps			$	19,689					$	—					$	19,689					$	—
Commodity derivatives			33,764						—						33,764						—
			$	53,453					$	—					$	53,453					$	—

The following table summarizes assets and liabilities measured at fair value on a recurring basis as of December 31, 2025, aggregated by the level in the fair value hierarchy within which those measurements fall:

			Fair Value						Fair Value Measurements Using
									Quoted Prices in Active Markets for Identical Assets and Liabilities (Level 1)						Significant Other Observable Inputs (Level 2)						Significant Unobservable Inputs (Level 3)
			(In thousands)
Assets:
Investments:
Equities and equity funds			$	128,659					$	128,659					$	—					$	—
Corporate and government bonds			1,971						1,971						—						—
Bond market funds			73,004						73,004						—						—
			203,634						203,634						—						—
Commodity derivatives			42,880						—						42,880						—
			$	246,514					$	203,634					$	42,880					$	—
Liabilities:
Interest rate swaps			$	22,031					$	—					$	22,031					$	—
Commodity derivatives			31,440						—						31,440						—
			$	53,471					$	—					$	53,471					$	—

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Basin Electric’s reportable segments include the Electric Utility, Gasification, and Coal and Limestone Operations. Certain activities that support the reportable segments, ancillary projects, or operating segments that do not meet the quantitative threshold for a reportable segment are presented as Other. The operating segments are based on Basin Electric’s method of internal reporting that the Chief Operating Decision Maker (CODM) reviews to make decisions on overall resource allocation and to assess performance. The CODM is Basin Electric’s Chief Executive Officer and General Manager. The CODM reviews actual financial information and forecasted financial information at an operating segment level and primarily uses segment net margin and earnings for making decisions on resource allocation and assessing performance. The CODM uses segment net income in assessing financial performance on a monthly basis, reviewing and approving annual operating budgets and long-term forecasts, allocating capital or financial resources to our segments and in making strategic decisions.

The Electric Utility reportable segment provides wholesale electric service and other ancillary services to Basin Electric’s members throughout its service territory with its own electrical generation and transmission assets and various contractual arrangements.

The Gasification reportable segment includes Dakota Gasification Company (DGC). DGC operates a gasification facility that converts lignite coal into synthetic natural gas and other products including fertilizers, diesel exhaust fluid, carbon dioxide, and other oil and chemical products.

The Coal and Limestone Operations reportable segment purchases coal and coordinates deliveries of coal to Basin Electric’s Electric Utility generation facilities and Gasification operations. It also produces lime and limestone that is used for emissions control at the generation facilities.

Other consists of Basin Cooperative Services, Nemadji River Generation, and certain tax adjustments and other activity not associated with the reportable segments. Basin Cooperative Services provides certain nonutility property management services to Basin Electric. Nemadji River Generation owned an undivided interest in a proposed electric generation facility. In January 2026, Nemadji River Generation exited the project and the NRG subsidiary is expected to be fully dissolved by the end of 2026.

Substantially all of Basin Electric’s assets and revenues are located in the United States. Revenues and assets outside the United States were not material for the periods presented.

Major Customer – For the three months ended March 31, 2026 and 2025, revenues from a single customer, Upper Missouri, represented approximately 30.6 percent and 30.7 percent respectively, of Basin Electric’s consolidated revenues, all of which were attributable to the Electric Utility reportable segment. No other customer contributed 10 percent or more of consolidated revenues for the periods.

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Information on Basin Electric’s segments for the three months ended March 31, 2026 and 2025 was as follows:

			Three Months Ended March 31, 2026
			Electric Utility						Gasification						Coal and Limestone Operations						Total Reportable Segments
			(In thousands)
Operating revenue:
External			$	671,589					$	114,453					$	55,161					$	841,203
Intersegment			—						—						30,966						30,966
			671,589						114,453						86,127						872,169
Elimination of intersegment revenue																					(30,966)
Total operating revenue																					$	841,203
Less:
Electric fuel and purchased power			335,299						—						—
Electric operations and maintenance			181,712						—						—
Cost of products sold:
External			—						78,525						53,221
Intersegment			—						30,966						—
Nonelectric selling, general and administrative			—						23,740						2,150
Depreciation, depletion and amortization			49,697						10,346						5,000
Other (income) expense			(17,105)						(39,684)						3,065
Interest and other charges:
External			66,527						4,000						3,098
Intersegment			(3,792)						—						—
Income tax (benefit) expense			(1,112)						3,822						3,565
Net margin and earnings attributable to noncontrolling interest			—						—						6,200
Segment net margin and earnings			60,363						2,738						9,828						72,929
Elimination of intercompany gain																					(3,792)
Other net earnings																					6,230
Net margin and earnings attributable to Basin Electric																					$	75,367
Segment capital expenditures (a)			$	221,105					$	1,858					$	4,835					$	227,798
Other capital expenditures																					—
Total consolidated capital expenditures																					$	227,798

_______________

(a)Does not include accruals for property, plant and equipment as disclosed in the supplemental cash flow information to the consolidated statements of cash flows.

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			Three Months Ended March 31, 2025
			Electric Utility						Gasification						Coal and Limestone Operations						Total Reportable Segments
			(In thousands)
Operating revenue:
External			$	618,433					$	110,956					$	49,223					$	778,612
Intersegment			—						—						28,604						28,604
			618,433						110,956						77,827						807,216
Elimination of intersegment revenue																					(28,604)
Total operating revenue																					$	778,612
Less:
Electric fuel and purchased power			310,658						—						—
Electric operations and maintenance			177,243						—						—
Cost of products sold:
External			—						72,186						51,548
Intersegment			—						28,604						—
Nonelectric selling, general and administrative			—						22,240						2,395
Depreciation, depletion and amortization			51,505						10,019						4,599
Other (income) expense			(16,781)						(31,111)						1,693
Interest and other charges:
External			51,535						8,688						3,356
Intersegment			2,376						—						—
Income tax (benefit) expense			(275)						2,706						2,404
Net margin and earnings attributable to noncontrolling interest			—						—						6,316
Segment net margin and earnings (loss)			42,172						(2,376)						5,516						45,312
Elimination of intercompany loss																					2,376
Other net earnings																					14
Net margin and earnings attributable to Basin Electric																					$	47,702
Segment capital expenditures (a)			$	99,693					$	4,479					$	1,651					$	105,823
Other capital expenditures																					349
Total consolidated capital expenditures																					$	106,172

_______________

(a)Does not include accruals for property, plant and equipment as disclosed in the supplemental cash flow information to the consolidated statements of cash flows.

Information on Basin Electric’s segments as of March 31, 2026 and December 31, 2025 was as follows:

			March 31, 2026
			Electric Utility						Gasification						Coal and Limestone Operations						Total Reportable Segments
			(In thousands)
Segment total assets			$	9,027,074					$	1,106,862					$	571,572					$	10,705,508
Other assets																					35,171
Elimination of intersegment assets																					(1,258,027)
Total consolidated assets																					$	9,482,652

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			December 31, 2025
			Electric Utility						Gasification						Coal and Limestone Operations						Total Reportable Segments
			(In thousands)
Segment total assets			$	9,014,439					$	1,053,066					$	568,599					$	10,636,104
Other assets																					35,504
Elimination of intersegment assets																					(1,273,951)
Total consolidated assets																					$	9,397,657

LEGAL

We are involved in claims, legal proceedings, investigations, and regulatory matters arising in the normal course of business. We regularly analyze relevant information and, as necessary, estimate and record accrued liabilities for legal, regulatory enforcement and other matters in which a loss or range of loss is probable of occurring and can be reasonably estimated. We believe the effect on our consolidated operating results, financial position and cash flows, if any, for the disposition of all matters pending as of March 31, 2026, other than those discussed below, will not be material.

LITIGATION–On November 7, 2019, McKenzie Electric Cooperative, Inc. (McKenzie), a Class C Member of Basin Electric and a member of Class A Member Upper Missouri G&T Electric Cooperative, Inc. (Upper Missouri), filed a lawsuit in North Dakota State Court against both Basin Electric and Upper Missouri. The complaint brought multiple claims against Basin Electric, some of which have since been dismissed. McKenzie’s remaining claims against Basin Electric are: (1) breach of the wholesale power contract (WPC) between Basin Electric and Upper Missouri (either as an alleged three-tier contract among Basin Electric, Upper Missouri and McKenzie, or with McKenzie being a third-party beneficiary to the WPC) by including losses associated with Dakota Gas in rates; and (2) declaratory judgment that the WPC permits McKenzie to terminate its contract with Upper Missouri prior to the expiration of the contract. Summary judgment motions were argued in April 2025 and are currently pending before the court. In September 2025, the parties reached a non-binding settlement in principle, through which the parties agreed to a settlement of all claims and allegations related to the matter. The settlement in principle which has since been modified and agreed to in a formal settlement agreement, is contingent upon certain corporate and regulatory approvals, as applicable to certain of the parties. In the absence of those approvals and a stipulated dismissal, the Court in North Dakota has indicated that it plans to move forward with setting a trial date and ruling on pending motions until the parties inform the Court that the settlement has been finalized. At this time, while a loss is reasonably possible, Basin Electric does not believe that the amount of loss can be reasonably estimated pending finalization of a definitive settlement agreement and therefore has not currently made any accrual for this matter.

FERC PROCEEDINGS–Effective November 1, 2019, Basin Electric ceased qualifying for an exemption from FERC’s jurisdiction under the Federal Power Act. As part of its new compliance requirements, Basin Electric submitted its WPCs and Rate Schedule A to FERC for approval. FERC accepted Basin Electric’s WPCs and 2020 Rate Schedule A subject to hearing and settlement proceedings effective September 15, 2020, and dismissed Basin Electric’s 2019 Rate Schedule A as moot. FERC subsequently accepted and consolidated Basin Electric’s 2021 Rate Schedule A with the ongoing hearing and settlement proceedings effective January 1, 2021. The FERC presiding judge held a hearing on the WPCs and 2020 and 2021 Rate Schedules A from August 28, 2023, to October 27, 2023, and from February 5, 2024, through February 7, 2024. The FERC presiding judge issued his initial decision on June 11, 2024, addressing arguments raised by Class A Member Tri-State Generation and Transmission Association, Inc. (Tri-State), Class C Members McKenzie, Minnesota Valley Electric Cooperative (MVEC), and Wright-Hennepin Cooperative Electric Association (Wright-Hennepin), and the Sierra Club. In particular, the Sierra Club argued that Basin Electric should not be allowed to recover costs in its rates relating to certain of its coal generation assets; McKenzie argued that Basin Electric should not be allowed to recover costs in its rates relating to Dakota Gas; and Tri-State, MVEC, and

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Wright-Hennepin argued that Basin Electric’s calculation of rates for depreciation expense and transmission service are not just and reasonable. The Initial Decision remains pending before FERC on exceptions. FERC has not indicated when it intends to act on the initial decision. In addition, FERC action remains pending on Basin Electric’s 2022, 2023, 2024, and 2025 Rate Schedules A.

On July 16, 2025, Basin Electric received financing under the Rural Electrification Act of 1936. Basin Electric subsequently filed a motion at FERC to dismiss the active rate proceedings involving the WPCs and Rate Schedules A on the basis that, pursuant to Federal Power Act (FPA) Section 201(f), Basin Electric is no longer a public utility subject to FERC rate regulation and also filed notices of cancellation of its rate schedules, tariffs, and other agreements. On September 12, 2025, FERC issued an order accepting the notices of cancellation, finding that, due to Basin Electric’s change of jurisdictional status, it is no longer required to maintain tariff records with FERC. FERC denied rehearing and issued an order addressing the rehearing arguments. The cancellation order has since been appealed by Tri-State to the D.C. Circuit Court of Appeals and remains pending with the appellate court. MVEC has subsequently voluntarily dismissed its objections in this proceeding and withdrawn as a participant in the matter. In September 2025, Basin Electric and McKenzie reached a settlement in principle, through which McKenzie agreed to withdraw its objections to Basin Electric’s rates in the FERC proceedings and withdraw from any other FERC proceedings and/or appeals in which it had intervened against Basin Electric to the greatest extent possible. The settlement in principle is contingent upon execution of a mutually acceptable settlement agreement and corporate and regulatory approvals, as applicable to each party. See also “Litigation” above. On June 5, 2026, FERC denied the motion to dismiss on the basis that it “must ensure that jurisdictional rates charged to customers were just and reasonable.” Basin Electric considered these FERC proceedings and currently has not made an accrual.

RUS FINANCING–On June 10, 2025, McKenzie filed with FERC a complaint against Basin Electric. The complaint requests that FERC find that Basin Electric is not authorized to obtain financing under the Rural Electrification Act of 1936 and that FERC retain jurisdiction over Basin Electric notwithstanding Basin Electric receiving such financing. Basin Electric contested the allegations of the complaint, and further contested McKenzie’s right to the relief requested under the Federal Power Act. On May 21, 2026, FERC issued an order denying the complaint, finding that McKenzie had not demonstrated that Basin Electric's actions were in violation of either Section 204 of the Federal Power Act or its blanket authorization to obtain financing. It is possible that a party to the complaint proceeding may seek rehearing by June 21, 2026.

NORTHWEST RURAL PUBLIC POWER DISTRICT–On March 25, 2024, Northwest Rural Public Power District (NRPPD) filed with FERC a complaint against Basin Electric and Tri-State. The complaint requested that FERC find that NRPPD is permitted to withdraw its membership in Tri-State, terminate its wholesale electric service contract (WESC) with Tri-State, and that its withdrawal and termination is permissible under the wholesale power contract between Basin Electric and Tri-State. In December 2024, FERC issued its order denying the complaint, but finding that NRPPD’s withdrawal from Tri-State and termination of its WESC is not a breach of the wholesale power contract between Basin Electric and Tri-State. FERC denied rehearing and issued an order addressing the rehearing arguments. Basin Electric filed an appeal of the FERC order with the D.C. Circuit Court of Appeals and the matter remains pending with the appellate court. In April 2026, Basin Electric and NRPPD reached a settlement in principle, through which NRPPD will dismiss its pending appeal at the D.C. Circuit and the underlying FERC complaint. The settlement in principle is contingent on execution of a mutually acceptable settlement agreement and regulatory approval, as applicable to each party. Basin Electric considered this matter and currently has not made an accrual.

Additionally, NRPPD has filed a complaint against Basin Electric in federal district court in Nebraska. In its amended complaint, NRPPD seeks a declaratory judgment that Basin Electric and Tri-State are bound by the December 2024 FERC Order that NRPPD’s withdrawal as a member of Tri-State, and therefore as a Class C Member of Basin Electric, is not a breach of the wholesale power contract for the Eastern Interconnection between Basin Electric and Tri-State. NRPPD further claims that it is a third-party beneficiary of the wholesale power contract between Basin Electric and Tri-State, and that Basin Electric has breached its obligations to Tri-State under the wholesale power contract by failing to provide NRPPD with an exit fee. Additional claims were added against Basin Electric for tortious interference with contract,

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tortious interference with a business relationship, and tortious interference with a prospective business relationship. Basin Electric contests the allegations of the complaint and has filed a motion to dismiss, which remains pending with the court. In April 2026, Basin Electric and NRPPD reached a settlement in principle, through which NRPPD will dismiss the pending complaint. The settlement in principle is contingent on execution of a mutually acceptable settlement agreement and regulatory approval, as applicable to each party. Basin Electric considered this complaint and currently has not made an accrual.

OTHER

DEBT GUARANTEE–Basin Electric guarantees, on an unsecured basis, a certain debt obligation of Dakota Coal totaling $21.4 million as of March 31, 2026. In the event Dakota Coal defaults under this obligation, Basin Electric would be required to make payments under its guarantee.

Basin Electric provides wholesale electricity sales and other services to its members. Basin Electric had accounts receivable from its members related to member wholesale power agreements of $223.8 million and $202.4 million as of March 31, 2026 and December 31, 2025, respectively.

Other receivables include $2.8 million and $2.3 million as of March 31, 2026 and December 31, 2025, respectively, for amounts Basin Electric, as operating agent, and its subsidiaries, have billed to MBPP. Included in special funds on the consolidated balance sheets is Basin Electric’s advance to MBPP of approximately $17.0 million as of both March 31, 2026 and December 31, 2025.

CONTRACTUAL COMMITMENTS–Basin Electric provides and receives power, various materials, supplies and services to and from affiliates which are under the following agreements:

•POWER SUPPLY–Basin Electric provides all electric capacity, energy and transmission service needed to meet Dakota Gas’ Synfuels Plant requirements under an agreement that extends through 2050.

•SCREENED COAL–Dakota Gas’ Synfuels Plant provides screened coal to Basin Electric under an agreement that extends through 2037.

•COAL SUPPLY–Dakota Coal provides all coal requirements of Dakota Gas’ Synfuels Plant and Basin Electric’s AVS and LOS. This agreement extends through 2037.

•ADMINISTRATIVE SERVICES–Basin Electric provides various administrative and financial services to Dakota Gas, Dakota Coal, MLC and BCS.

•LIME SALES–Dakota Coal provides lime to Basin Electric’s AVS and LRS. The agreement with AVS extends through 2030.

•LIMESTONE SALES–Dakota Coal provides limestone to Basin Electric’s LOS under an agreement that extends through 2040.

•WATER SUPPLY–Basin Electric provides water supply facilities for use by Dakota Gas’ Synfuels Plant.

•SALE OF NATURAL GAS–Dakota Gas sells natural gas to Basin Electric for operation of utility gas generating plants and AVS (includes pipeline related costs).

•USE OF TRANSMISSION ASSETS–Basin Electric uses certain Dakota Gas transmission assets for a fee under an agreement that extends through 2047.

•SALE OF FERTILIZERS, UREA AND DEF-Dakota Gas sells fertilizers, urea and DEF to Basin Electric and MBPP for operation of power generation units.

•PROJECT SERVICES–Basin Electric provides the use of operational assets to Dakota Gas’ Synfuels Plant.

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•OTHER-Dakota Coal provides the maintenance of railroad facilities to Dakota Gas' Synfuels Plant and Basin Electric under an agreement that extends through 2040.

Related party amounts that were not eliminated in consolidation in accordance with ASC 980 were billed as follows for the three months ended March 31, 2026 and 2025:

			March 31, 2026						March 31, 2025
			(In thousands)
Sales of goods and services to:
Dakota Gas
Power supply			$	19,343					$	15,892
Administrative services			7,879						6,917
Water supply			700						643
Project and other services			136						267
Dakota Coal
Administrative services			537						630
Total			$	28,595					$	24,349
Goods and services provided by:
Dakota Gas
Screened coal			$	17,251					$	18,426
Natural gas			9,674						2,638
Transmission and other misc. services			264						257
Fertilizers, urea and DEF			1,331						984
Dakota Coal
Coal supply			31,042						23,941
Lime			4,074						4,214
Limestone			429						441
Other			9						—
Total			$	64,074					$	50,901

Various other intercompany management, administrative and financial services were performed, which were not significant.

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ATTACHMENTS / EXHIBITS

EX-31.1

EX-31.2

EX-32.1

EX-32.2

EX-95

XBRL TAXONOMY EXTENSION SCHEMA DOCUMENT

XBRL TAXONOMY EXTENSION CALCULATION LINKBASE DOCUMENT

XBRL TAXONOMY EXTENSION DEFINITION LINKBASE DOCUMENT

XBRL TAXONOMY EXTENSION LABEL LINKBASE DOCUMENT

XBRL TAXONOMY EXTENSION PRESENTATION LINKBASE DOCUMENT

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