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of Contents](#i2bbbbcf22f934398bf3fcad73ef0f1bd_7)\n\nUNITED STATES\n\nSECURITIES AND EXCHANGE COMMISSION\n\nWashington, D.C. 20549\n\nFORM 10-Q\n\n \n\n☒\nQuarterly report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 for 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\nfor the transition period from             to\n\nCommission\nFile NumberExact name of registrant as specified in its charter;\nState of Incorporation;\nAddress and Telephone NumberIRS Employer\nIdentification No.\n\n1-14756Ameren Corporation43-1723446\n\n(Missouri Corporation)\n\n1901 Chouteau Avenue\n\nSt. Louis, Missouri 63103\n\n(314) 621-3222\n\n1-2967Union Electric Company43-0559760\n\n(Missouri Corporation)\n\n1901 Chouteau Avenue\n\nSt. Louis, Missouri 63103\n\n(314) 621-3222\n\n1-3672Ameren Illinois Company37-0211380\n\n(Illinois Corporation)\n\n10 Richard Mark Way\n\nCollinsville, Illinois 62234\n\n(618) 343-8150\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\nCommon Stock, $0.01 par value per shareAEENew York Stock Exchange\n\n[Table of Contents](#i2bbbbcf22f934398bf3fcad73ef0f1bd_7)\n\nIndicate by check mark whether each 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.\n\nAmeren CorporationYes☒No☐\n\nUnion Electric CompanyYes☒No☐\n\nAmeren Illinois CompanyYes☒No☐\n\nIndicate by check mark whether each 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).\n\nAmeren CorporationYes☒No☐\n\nUnion Electric CompanyYes☒No☐\n\nAmeren Illinois CompanyYes☒No☐\n\nIndicate by check mark whether each 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\nAmeren CorporationLarge accelerated filer☒Accelerated filer☐Non-accelerated filer☐\n\nSmaller reporting company☐Emerging growth company☐\n\nUnion Electric CompanyLarge accelerated filer☐Accelerated filer☐Non-accelerated filer☒\n\nSmaller reporting company☐Emerging growth company☐\n\nAmeren Illinois CompanyLarge accelerated filer☐Accelerated filer☐Non-accelerated filer☒\n\nSmaller 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\nAmeren Corporation☐\n\nUnion Electric Company☐\n\nAmeren Illinois Company☐\n\nIndicate by check mark whether each registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).\n\nAmeren CorporationYes☐No☒\n\nUnion Electric CompanyYes☐No☒\n\nAmeren Illinois CompanyYes☐No☒\n\nThe number of shares outstanding of each registrant’s classes of common stock as of April 30, 2026, was as follows:\n\nRegistrantTitle of each class of common stockShares outstanding\n\nAmeren CorporationCommon stock, $0.01 par value per share276,751,616 \n\nUnion Electric CompanyCommon stock, $5 par value per share, held by Ameren Corporation102,123,834 \n\nAmeren Illinois CompanyCommon stock, no par value, held by Ameren Corporation25,452,373 \n\nThis combined Form 10-Q is separately filed by Ameren Corporation, Union Electric Company, and Ameren Illinois Company. Each registrant hereto is filing on its own behalf all of the information contained in this quarterly report that relates to such registrant. Each registrant hereto is not filing any information that does not relate to such registrant, and therefore makes no representation as to any such information.\n\n[Table of Contents](#i2bbbbcf22f934398bf3fcad73ef0f1bd_7)\n\nTABLE OF CONTENTS\n\n  Page\n\n[Glossary of Terms and Abbreviations](#i2bbbbcf22f934398bf3fcad73ef0f1bd_10)\n\n[1](#i2bbbbcf22f934398bf3fcad73ef0f1bd_10)\n\n[Forward-looking Statements](#i2bbbbcf22f934398bf3fcad73ef0f1bd_16)\n\n[1](#i2bbbbcf22f934398bf3fcad73ef0f1bd_16)\n\n[PART I. Financial Information](#i2bbbbcf22f934398bf3fcad73ef0f1bd_19)"}