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of Contents](#ie41c29dc85f24c7592e001ecbbe30268_7)\n\nUNITED STATES\n\nSECURITIES AND EXCHANGE COMMISSION\n\nWASHINGTON, D.C. 20549\n\n__________________________________\n\nFORM 10-Q\n\n(Mark One)\n\n☒QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934\n\nFor the quarterly period ended March 31, 2026\n\nOR\n\n☐TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934\n\nFor the transition period from to\n\nCommission File No. 333-212006\n\nTRI-STATE GENERATION AND TRANSMISSION ASSOCIATION, INC.\n\n(Exact name of registrant as specified in its charter)\n\nColorado84-0464189\n\n(State or other jurisdiction of incorporation or\n\norganization)\n\n(I.R.S. employer identification\n\nnumber)\n\n1100 West 116th Avenue\n\nWestminster,Colorado80234\n\n(Address of principal executive offices)\n\n(Zip Code)\n\n(303) 452-6111\n\n(Registrant’s telephone number, including area code)\n\nIndicate 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 ☒ (Note: The registrant is not subject to the filing requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934 (the “Exchange Act”), but voluntarily files reports with the Securities and Exchange Commission).\n\nIndicate 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 ☐\n\nIndicate 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 ☐\n\nNon-accelerated Filer ☒ Smaller reporting company ☐ Emerging growth company ☐\n\nIf 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. ☐\n\nIndicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No ☒\n\nSecurities registered pursuant to Section 12(b) of the Act:\n\nTitle of each classTrading Symbol(s)Name of each exchange on which registered\n\nNoneNoneNone\n\nIndicate the number of shares outstanding of each of the issuer’s classes of common stock, as of the latest practicable date. The registrant is a membership corporation and has no authorized or outstanding equity securities.\n\n[Table of Contents](#ie41c29dc85f24c7592e001ecbbe30268_7)\n\nTRI-STATE GENERATION AND TRANSMISSION ASSOCIATION, INC.\n\nINDEX TO QUARTERLY REPORT ON FORM 10-Q\n\nFOR THE QUARTER ENDED MARCH 31, 2026\n\nPage Number\n\n[PART I. FINANCIAL INFORMATION](#ie41c29dc85f24c7592e001ecbbe30268_16)\n\n[Item 1.](#ie41c29dc85f24c7592e001ecbbe30268_19)\n\n[Financial Statements](#ie41c29dc85f24c7592e001ecbbe30268_19)\n\n[Consolidated Statements of Financial Position (Unaudited)](#ie41c29dc85f24c7592e001ecbbe30268_22)\n\n[1](#ie41c29dc85f24c7592e001ecbbe30268_22)\n\n[Consolidated Statements of Operations (Unaudited)](#ie41c29dc85f24c7592e001ecbbe30268_25)\n\n[2](#ie41c29dc85f24c7592e001ecbbe30268_25)\n\n[Consolidated Statements of Comprehensive Income (Unaudited)](#ie41c29dc85f24c7592e001ecbbe30268_28)\n\n[3](#ie41c29dc85f24c7592e001ecbbe30268_28)\n\n[Consolidated Statements of Equity (Unaudited)](#ie41c29dc85f24c7592e001ecbbe30268_31)\n\n[4](#ie41c29dc85f24c7592e001ecbbe30268_31)\n\n[Consolidated Statements of Cash Flows (Unaudited)](#ie41c29dc85f24c7592e001ecbbe30268_34)\n\n[5](#ie41c29dc85f24c7592e001ecbbe30268_34)\n\n[Notes to Unaudited Consolidated Financial Statements](#ie41c29dc85f24c7592e001ecbbe30268_37)\n\n[6](#ie41c29dc85f24c7592e001ecbbe30268_37)\n\n[Item 2.](#ie41c29dc85f24c7592e001ecbbe30268_100)\n\n[Management’s Discussion and Analysis of Financial Condition and Results of Operations](#ie41c29dc85f24c7592e001ecbbe30268_100)\n\n[26](#ie41c29dc85f24c7592e001ecbbe30268_100)\n\n[Item 3.](#ie41c29dc85f24c7592e001ecbbe30268_154)\n\n[Quantitative and Qualitative Disclosures About Market Risk](#ie41c29dc85f24c7592e001ecbbe30268_154)\n\n[34](#ie41c29dc85f24c7592e001ecbbe30268_154)\n\n[Item 4.](#ie41c29dc85f24c7592e001ecbbe30268_157)\n\n[Controls and Procedures](#ie41c29dc85f24c7592e001ecbbe30268_157)\n\n[34](#ie41c29dc85f24c7592e001ecbbe30268_157)\n\n[PART II. OTHER INFORMATION](#ie41c29dc85f24c7592e001ecbbe30268_160)\n\n[Item 1.](#ie41c29dc85f24c7592e001ecbbe30268_163)\n\n[Legal Proceedings](#ie41c29dc85f24c7592e001ecbbe30268_163)\n\n[35](#ie41c29dc85f24c7592e001ecbbe30268_163)\n\n[Item 4.](#ie41c29dc85f24c7592e001ecbbe30268_166)\n\n[Mine Safety Disclosures](#ie41c29dc85f24c7592e001ecbbe30268_166)\n\n[35](#ie41c29dc85f24c7592e001ecbbe30268_166)\n\n[Item 6.](#ie41c29dc85f24c7592e001ecbbe30268_169)\n\n[Exhibits](#ie41c29dc85f24c7592e001ecbbe30268_169)\n\n[35](#ie41c29dc85f24c7592e001ecbbe30268_169)\n\n[SIGNATURES](#ie41c29dc85f24c7592e001ecbbe30268_172)\n\ni\n\n[Table of Contents](#ie41c29dc85f24c7592e001ecbbe30268_7)\n\nGLOSSARY\n\nThe following abbreviations and acronyms used in this quarterly report on Form 10-Q are defined below:\n\nAbbreviations or AcronymsDefinition\n\n2022 Revolving Credit AgreementAmended and Restated Credit Agreement, dated as of April 25, 2022, between Tri-State and CFC, as administrative agent\n\n2023 ERPTri-State's 2023 Electric Resource Plan filed with the COPUC\n\n2026 Credit AgreementSecond Amended and Restated Credit Agreement, dated as of April 21, 2026, between Tri-State and CFC, as administrative agent\n\nASCAccounting Standards Codification\n\nASUAccounting Standards Update\n\nBasinBasin Electric Power Cooperative\n\nBoardBoard of Directors\n\nBYORBring Your Own Resource\n\nCFCNational Rural Utilities Cooperative Finance Corporation\n\nCoBankCoBank, ACB\n\nColowyo CoalColowyo Coal Company L.P., a subsidiary of Tri-State\n\nCOPUCColorado Public Utilities Commission\n\nCRPPDChimney Rock Public Power District\n\nD.C. Circuit Court of AppealsUnited States Court of Appeals for the District of Columbia Circuit\n\nDSRDebt Service Ratio (as defined in our Master Indenture)\n\nECREquity to Capitalization Ratio (as defined in our Master Indenture)\n\nEPAEnvironmental Protection Agency\n\nFASBFinancial Accounting Standards Board\n\nFERCFederal Energy Regulatory Commission\n\nFitchFitch Ratings Inc.\n\nFPAFederal Power Act, as amended\n\nGAAPAccounting principles generally accepted in the United States\n\nIRAInflation Reduction Act of 2022\n\nJemezJemez Mountains Electric Cooperative, Inc.\n\nkWhkilowatt hour\n\nLPEALa Plata Electric Association, Inc.\n\nMaster IndentureMaster First Mortgage Indenture, Deed of Trust and Security Agreement, dated effective as of December 15, 1999, between Tri-State and U.S. Bank Trust Company, National Association, as successor trustee\n\nMBPPMissouri Basin Power Project\n\nMembersTri-State's Utility Members and Non-Utility Members\n\nMPEIMountain Parks Electric, Inc.\n\nMoody’sMoody’s Investors Services, Inc.\n\nMWmegawatt\n\nMWhmegawatt hour\n\nNew Era ProgramUSDA's Empowering Rural America Program\n\nNon-Utility MembersTri-State's non-utility members\n\nNRPPDNorthwest Rural Public Power District\n\nOATTOpen Access Transmission Tariff\n\nPREMAPanhandle Rural Electric Membership Association\n\nRenewable Revolving Credit Agreement\n\nRenewable Revolving Credit Agreement, dated as of June 18, 2025, between Tri-State and CFC, as administrative agent\n\nRPPDRoosevelt Public Power District\n\nRUSRural Utilities Service\n\nii\n\n[Table of Contents](#ie41c29dc85f24c7592e001ecbbe30268_7)\n\nS&PS & P Global Ratings\n\nSECSecurities and Exchange Commission\n\nSPPSouthwest Power Pool\n\nSpringerville PartnershipSpringerville Unit 3 Partnership LP, a subsidiary of Tri-State\n\nSpringerville Unit 3Springerville Generating Station Unit 3\n\nTerm SOFRthe implied rate on the future movement in the Secured Overnight Financing Rate (or \"SOFR\") over a future reference period\n\nTri-State, We, Our, Us, the AssociationTri-State Generation and Transmission Association, Inc.\n\nUnited PowerUnited Power, Inc.\n\nUSDAUnited States Department of Agriculture\n\nUtility MembersTri-State's electric distribution member systems\n\nWBPPDWheat Belt Public Power District\n\niii\n\n[Table of Contents](#ie41c29dc85f24c7592e001ecbbe30268_7)\n\nFORWARD-LOOKING STATEMENTS\n\nThis quarterly report on Form 10-Q contains “forward-looking statements.” All statements, other than statements of historical facts, that address activities, events or developments that Tri-State expects or anticipates to occur in the future, including matters such as the timing of various regulatory and other actions, future capital expenditures, future resources and generation portfolio, future use of deferred revenue, business strategy, member withdraws and development, construction, operation, or closure of facilities (often, but not always, identified through the use of words or phrases such as “will likely result,” “are expected to,” “will continue,” “is anticipated,” “estimated,” “forecast,” “projection,” “target” and “outlook”) are forward-looking statements.\n\nAlthough Tri-State believes that in making these forward-looking statements its expectations are based on reasonable assumptions, any forward-looking statement involves uncertainties and there are important factors that could cause actual results to differ materially from those expressed or implied by these forward-looking statements.\n\niv\n\n[Table of Contents](#ie41c29dc85f24c7592e001ecbbe30268_7)\n\nPART I. FINANCIAL INFORMATION"}