Other Events. On August 24, 2026, Ameren Illinois Company (“Ameren Illinois”), a subsidiary of Ameren Corporation, sold $400 million principal amount of its 5.50% First Mortgage Bonds due 2036 (the “Bonds”). The Bonds were offered pursuant to a Registration Statement on Form S-3 (File No. 333-297949-01), which became effective on August 4, 2026, and a Prospectus Supplement dated August 17, 2026, to a Prospectus dated August 4, 2026. Ameren Illinois received net offering proceeds of approximat…

Results of Operations and Financial Condition. On July 30, 2026, Ameren Corporation (“Ameren”) issued a press release announcing its earnings for the quarterly period ended June 30, 2026. The press release is attached as Exhibit 99.1 and is incorporated herein by reference. The information furnished pursuant to this Item 2.02, including Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”) or otherwise subj…

Other Events. On June 29, 2026, Union Electric Company, doing business as Ameren Missouri (“Ameren Missouri”), a subsidiary of Ameren Corporation, sold $500 million principal amount of its 5.75% First Mortgage Bonds due 2056 (the “Bonds”). The Bonds were offered pursuant to a Registration Statement on Form S-3 (File No. 333-274977-02), which became effective on October 13, 2023, and a Prospectus Supplement dated June 15, 2026, to a Prospectus dated October 13, 2023. Ameren Missouri received n…

Results of Operations and Financial Condition. On May 5, 2026, Ameren Corporation (“Ameren”) issued a press release announcing its earnings for the quarterly period ended March 31, 2026. The press release is attached as Exhibit 99.1 and is incorporated herein by reference. The information furnished pursuant to this Item 2.02, including Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”) or otherwise subje…

Other Events. On March 4, 2026, Ameren Corporation (“Ameren”) sold $400 million principal amount of its 5.00% Senior Notes due 2036 (the “Notes”). The Notes were offered pursuant to a Registration Statement on Form S-3 (File No. 333-274977), which became effective on October 13, 2023, and a Prospectus Supplement dated February 26, 2026, to a Prospectus dated October 13, 2023. Ameren received net offering proceeds of approximately $396.6 million, before expenses, upon closing of the transactio…

Other Events. On February 27, 2026, Union Electric Company, doing business as Ameren Missouri (“Ameren Missouri”), a subsidiary of Ameren Corporation, sold $450 million principal amount of its 4.80% First Mortgage Bonds due 2036 (the “2036 Bonds”) and $450 million principal amount of its 5.55% First Mortgage Bonds due 2056 (the “2056 Bonds”, and together with the 2036 Bonds, the “Bonds”). The Bonds were offered pursuant to a Registration Statement on Form S-3 (File No. 333-274977-02), which b…

Results of Operations and Financial Condition. On February 11, 2026, Ameren Corporation (“Ameren”) issued a press release announcing its earnings for the fourth quarter and year ended December 31, 2025, and providing earnings guidance. The press release is attached as Exhibit 99.1 and is incorporated herein by reference. The information furnished pursuant to this Item 2.02, including Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, a…

Director — Timothy S. Rausch: Mr. Timothy S. Rausch was elected to the Board of Directors and appointed to committees effective March 1, 2026.

Director — Jamie L. Engstrom: Ms. Engstrom was elected to the Board and appointed to committees effective January 1, 2026.

Entry into a Material Definitive Agreement. Reference is made to Note 4 – Short-term Debt and Liquidity to the financial statements under Part II, Item 8. Financial Statements and Supplementary Data of the Annual Report on Form 10-K for the year ended December 31, 2024, of registrants Ameren Corporation (“Ameren”), Union Electric Company, doing business as Ameren Missouri (“Ameren Missouri”) and Ameren Illinois Company, doing business as Ameren Illinois (“Ameren Illinois”) for a discussion of…

Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant. The information set forth in

Results of Operations and Financial Condition. On November 5, 2025, Ameren Corporation (“Ameren”) issued a press release announcing its earnings for the quarterly period ended September 30, 2025. The press release is attached as Exhibit 99.1 and is incorporated herein by reference. The information furnished pursuant to this Item 2.02, including Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”) or otherw…

Group President, Ameren Utilities (Mr. Moehn); Executive Vice President and Chief Financial Officer (Mr. Singh) — Michael L. Moehn; Leonard P. Singh: Mr. Moehn and Mr. Singh have been promoted to new roles within the company with increased responsibilities and compensation.

Chairman and President of Ameren Missouri — Mark C. Birk: Mark C. Birk retired from his position and was succeeded by Michael L. Moehn as Interim Chairman and President.

Other Events. On September 26, 2025, Ameren Illinois Company (“Ameren Illinois”), a subsidiary of Ameren Corporation, sold $350 million principal amount of its 5.625% First Mortgage Bonds due 2055 (the “Bonds”). These Bonds are a further issuance of the 5.625% First Mortgage Bonds due 2055 previously issued on March 3, 2025, in the principal amount of $350 million. The Bonds were offered pursuant to a Registration Statement on Form S-3 (File No. 333-274977-01), which became effective on Octob…

Results of Operations and Financial Condition. On July 31, 2025, Ameren Corporation (“Ameren”) issued a press release announcing its earnings for the quarterly period ended June 30, 2025. The press release is attached as Exhibit 99.1 and is incorporated herein by reference. The information furnished pursuant to this Item 2.02, including Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”) or otherwise subj…

Entry into a Material Definitive Agreement. On May 12, 2025, Ameren entered into forward sale agreements with each of Goldman Sachs & Co. LLC, JPMorgan Chase Bank, National Association, Barclays Bank PLC and Wells Fargo Bank, National Association (each, a “Forward Purchaser”), relating to the Base Shares (each, a “Base Forward Sale Agreement”, and, collectively, the “Base Forward Sale Agreements”). On May 13, 2025, Ameren entered into additional forward sale agreements with each Forward Purch…

Other Events. On May 12, 2025, Ameren entered into the Underwriting Agreement with the Underwriters, the Forward Sellers and the Forward Purchasers, related to the registered public offering and sale by the Forward Sellers of the Base Shares, which granted the Underwriters a 30-day option to purchase an amount up to the Option Shares. On May 13, 2025, the Underwriters exercised their option in full. On May 14, 2025, the Forward Sellers sold to the Underwriters the Shares in connection with th…

Results of Operations and Financial Condition. On May 1, 2025, Ameren Corporation (“Ameren”) issued a press release announcing its earnings for the quarterly period ended March 31, 2025. The press release is attached as Exhibit 99.1 and is incorporated herein by reference. The information furnished pursuant to this Item 2.02, including Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”) or otherwise subje…

Director — Noelle K. Eder: Resigned due to personal reasons related to a change in primary employment requiring her to reside outside of the United States.

Other Events. On April 4, 2025, Union Electric Company, doing business as Ameren Missouri (“Ameren Missouri”), a subsidiary of Ameren Corporation, sold $500 million principal amount of its 5.25% First Mortgage Bonds due 2035 (the “Bonds”). The Bonds were offered pursuant to a Registration Statement on Form S-3 (File No. 333-274977-02), which became effective on October 13, 2023, and a Prospectus Supplement dated March 26, 2025, to a Prospectus dated October 13, 2023. Ameren Missouri received…

Director — Kimberly J. Harris: Ms. Harris resigned due to personal health reasons.

Other Events. On March 7, 2025, Ameren Corporation (“Ameren”) sold $750 million principal amount of its 5.375% Senior Notes due 2035 (the “Notes”). The Notes were offered pursuant to a Registration Statement on Form S-3 (File No. 333-274977), which became effective on October 13, 2023, and a Prospectus Supplement dated February 27, 2025, to a Prospectus dated October 13, 2023. Ameren received net offering proceeds of approximately $743.8 million, before expenses, upon closing of the transacti…

Other Events. On March 3, 2025, Ameren Illinois Company (“Ameren Illinois”), a subsidiary of Ameren Corporation, sold $350 million principal amount of its 5.625% First Mortgage Bonds due 2055 (the “Bonds”). The Bonds were offered pursuant to a Registration Statement on Form S-3 (File No. 333-274977-01), which became effective on October 13, 2023, and a Prospectus Supplement dated February 24, 2025, to a Prospectus dated October 13, 2023. Ameren Illinois received net offering proceeds of appro…

Results of Operations and Financial Condition. On February 13, 2025, Ameren Corporation (“Ameren”) issued a press release announcing its earnings for the fourth quarter and year ended December 31, 2024, and providing earnings guidance. The press release is attached as Exhibit 99.1 and is incorporated herein by reference. The information furnished pursuant to this Item 2.02, including Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, a…