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of Contents](#TOC)\n\n​\n\n​\n\n**UNITED STATES SECURITIES AND EXCHANGE COMMISSION**\n\nWashington, D.C. 20549\n\n**FORM ****10-Q**\n\n​\n\n☒\n\nQUARTERLY REPORT UNDER SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended **March 31,****2026**\n\n​\n\n​\n\n☐\n\nTRANSITION REPORT UNDER SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from                      to                     \n\n​\n\nCommission file number: **001-40893**\n\n​\n\n**CATALYST BANCORP, INC.**\n\n(Exact name of registrant as specified in its charter)\n\n​\n\n**Louisiana**\n\n  ​ ​ ​\n\n**86-2411762**\n\n(State or other jurisdiction of incorporation\nof organization)\n\n​\n\n(I.R.S. Employer Identification No.)\n\n​\n\n**235 N. Court Street****,****Opelousas****,****Louisiana********70570**\n\n(Address of principal executive offices; Zip Code) \n\n**(****337****)****948-3033**\n\n(Registrant’s telephone number, including area code)\n\n**None**\n\n(Former name, former address and former fiscal year, if changed since last report)\n\nSecurities registered pursuant to Section 12(b) of the Act:\n\n​\n\nTitle of each class\n\n  ​ ​ ​\n\nTrading Symbol(s)\n\n  ​ ​ ​\n\nName of each exchange on which registered\n\n**Common Stock**\n\n​\n\n**CLST**\n\n​\n\n**Nasdaq****Capital Market**\n\n​\n\nIndicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 and 15(d) of the Exchange Act 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 ☐\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.\n\n​\n\n​\n\n​\n\n​\n\n​\n\nLarge accelerated filer\n\n☐\n\nAccelerated filer\n\n☐\n\nNon-accelerated filer\n\n☒\n\nSmaller reporting company\n\n☒\n\nEmerging growth company\n\n☒\n\n​\n\n​\n\n​\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\n​\n\nThere were 4,051,896 shares of Registrant’s common stock, par value of $0.01 per share, issued and outstanding as of May 12, 2026.\n\n​\n\n​\n\n​\n\n​\n\n[Table of Contents](#TOC)\n\n**CATALYST BANCORP, INC.**\n\n**FORM 10-Q**\n\nTABLE OF CONTENTS\n\n​\n\n​\n\n​\n\n[**PART I**](#PARTIFINANCIALINFORMATION_226558)\n\n[**FINANCIAL INFORMATION**](#PARTIFINANCIALINFORMATION_226558)\n\n​\n\n​\n\n​\n\n​\n\n​\n\n​\n\n[Item 1.](#ITEM1FINANCIALSTATEMENTS_463599)\n\n[Financial Statements (Unaudited)](#ITEM1FINANCIALSTATEMENTS_463599)\n\n​\n\n​\n\n​\n\n​\n\n​\n\n​\n\n​\n\n[Consolidated Statements of Financial Condition](#STATEMENTSOFFINANCIALCONDITION_92809)\n\n​\n\n2\n\n​\n\n​\n\n​\n\n​\n\n​\n\n[Consolidated Statements of Income](#STATEMENTSOFINCOME_817104)\n\n​\n\n3\n\n​\n\n​\n\n​\n\n​\n\n​\n\n[Consolidated Statements of Comprehensive Income](#STATEMENTSOFCOMPREHENSIVEINCOME_284263)\n\n​\n\n4\n\n​\n\n​\n\n​\n\n​\n\n​\n\n[Consolidated Statements of Changes in Shareholders' Equity](#STATEMENTSOFCHANGESINEQUITY_924291)\n\n​\n\n5\n\n​\n\n​\n\n​\n\n​\n\n​\n\n[Consolidated Statements of Cash Flows](#STATEMENTSOFCASHFLOWS_980661)\n\n​\n\n6\n\n​\n\n​\n\n​\n\n​\n\n​\n\n[Notes to Unaudited Consolidated Financial Statements](#NOTESTOFINANCIAL)\n\n​\n\n7\n\n​\n\n​\n\n​\n\n​\n\n[Item 2.](#ITEM2MANAGEMENTSDISCUSSIONANDANALYSISOFF)\n\n[Management's Discussion and Analysis of Financial Condition and Results of Operations](#ITEM2MANAGEMENTSDISCUSSIONANDANALYSISOFF)\n\n​\n\n27\n\n​\n\n​\n\n​\n\n​\n\n[Item 3.](#ITEM3QUANTITATIVEANDQUALITATIVEDISCLOSUR)\n\n[Quantitative and Qualitative Disclosures about Market Risk](#ITEM3QUANTITATIVEANDQUALITATIVEDISCLOSUR)\n\n​\n\n42\n\n​\n\n​\n\n​\n\n​\n\n[Item 4.](#ITEM4CONTROLSANDPROCEDURES_808200)\n\n[Controls and Procedures](#ITEM4CONTROLSANDPROCEDURES_808200)\n\n​\n\n43\n\n​\n\n​\n\n​\n\n​\n\n[**PART II**](#PARTIIOTHERINFORMATION_513062)\n\n[**OTHER INFORMATION**](#PARTIIOTHERINFORMATION_513062)\n\n​\n\n44\n\n​\n\n​\n\n​\n\n​\n\n[Item 1.](#ITEM1LEGALPROCEEDINGS_729898)\n\n[Legal Proceedings](#ITEM1LEGALPROCEEDINGS_729898)\n\n​\n\n44\n\n​\n\n​\n\n​\n\n​\n\n[Item 1A.](#ITEM1ARISKFACTORS_818937)\n\n[Risk Factors](#ITEM1ARISKFACTORS_818937)\n\n​\n\n44\n\n​\n\n​\n\n​\n\n​\n\n[Item 2.](#ITEM2UNREGISTEREDSALESOFEQUITYSECURITIES)\n\n[Unregistered Sales of Equity Securities and Use of Proceeds](#ITEM2UNREGISTEREDSALESOFEQUITYSECURITIES)\n\n​\n\n44\n\n​\n\n​\n\n​\n\n​\n\n[Item 3.](#ITEM3DEFAULTSUPONSENIORSECURITIES_473626)\n\n[Defaults Upon Senior Securities](#ITEM3DEFAULTSUPONSENIORSECURITIES_473626)\n\n​\n\n44\n\n​\n\n​\n\n​\n\n​\n\n[Item 4.](#ITEM4MINESAFETYDISCLOSURES_74341)\n\n[Mine Safety Disclosures](#ITEM4MINESAFETYDISCLOSURES_74341)\n\n​\n\n44\n\n​\n\n​\n\n​\n\n​\n\n[Item 5](#ITEM5OTHERINFORMATION_843666)\n\n[Other Information](#ITEM5OTHERINFORMATION_843666)\n\n​\n\n44\n\n​\n\n​\n\n​\n\n​\n\n[Item 6.](#ITEM6EXHIBITS_277635)\n\n[Exhibits](#ITEM6EXHIBITS_277635)\n\n​\n\n45\n\n​\n\n​\n\n​\n\n[SIGNATURES](#SIGNATURES_737080)\n\n​\n\n46\n\n​\n\n​\n\ni\n\n[Table of Contents](#TOC)\n\nPART I. FINANCIAL INFORMATION"}