AMEREN CORP

Our core strategy is driven by the following three pillars, which allow us to deliver on opportunities to benefit our customers, communities, and shareholders:

Key announcements, updates, and regulatory outcomes

The PPRA became effective in August 2025. The law includes certain provisions that affect the regulation of Ameren Missouri’s electric and natural gas businesses. These provisions create modifications to the PISA and integrated resource planning, require electric utilities to submit service tariff schedules for certain large load customers, allow the MoPSC to authorize inclusion of construction work in progress in rate base for new natural gas-fired generation facilities and new generation facilities approved through integrated resource planning, and allow natural gas utilities to file regulatory rate reviews using a future test year, among other things.

In April 2025, the MoPSC issued an order in Ameren Missouri’s 2024 electric service regulatory rate review, approving nonunanimous stipulations and agreements. The order authorized an increase of $355 million to Ameren Missouri’s annual revenue requirement for electric retail service, effective June 1, 2025. The approved revenue requirement was based on infrastructure investments as of December 31, 2024. The order did not explicitly specify an ROE, capital structure, rate base, or any rate base disallowances. The order provides for the continued use of all existing riders and trackers. The order also changed annualized depreciation, regulatory asset and liability amortization amounts, and the base level of expenses for trackers. On an annualized basis, these changes reflect an increase in “Depreciation and amortization” of approximately $70 million, among other expense changes, on Ameren’s and Ameren Missouri’s consolidated statements of income.

In July 2025, the MoPSC issued an order in Ameren Missouri’s 2024 natural gas delivery service regulatory rate review, approving a unanimous stipulation and agreement. The order authorized an increase of $32 million to Ameren Missouri’s annual revenue requirement for natural gas delivery service, effective September 1, 2025. The order did not explicitly specify an ROE, capital structure, rate base, or any rate base disallowances. The order provides for the continued use of all of Ameren Missouri’s existing riders and trackers.

In November 2025, the MoPSC approved Ameren Missouri’s request to modify its existing large primary service tariff to require customers requesting 75 MWs or more of demand and who are served at transmission level voltage to comply with additional tariff terms. The additional terms include a service term of 12 years plus a ramp period of up to five years to reach peak demand, minimum demand charges of 80% of contracted capacity, customer exit terms and fees, and customer credit and collateral requirements, among other terms. In addition, new customer programs would be available under this tariff, which allow customers to support renewable generation, battery storage, and/or nuclear generation through incremental payments. The MoPSC order also includes an earnings sharing mechanism that would apply if Ameren Missouri’s earned ROE for a calendar year exceeds 9.74%, which can be adjusted by the MoPSC in future electric rate orders. If this were to occur, Ameren Missouri would defer 65% of the return in excess of the 9.74% ROE to a regulatory liability, which would be returned to retail electric customers in a future rate review. In addition, if large load customer revenues were reduced in a calendar year due to certain events, as determined by the MoPSC, Ameren Missouri may defer a portion of the reduced revenues to a regulatory asset to be included in its revenue requirement in the next electric rate review. In February 2026, Ameren Missouri executed electric service agreements with large load customers consistent with the tariff terms discussed above, representing 2.2 gigawatts of demand. Ameren and Ameren Missouri do not expect a material impact to their results of operations, financial position, or liquidity in 2026 related to these agreements.

In August 2025, Ameren Missouri filed for a CCN to construct the Reform Solar Project (250-MW facility). Ameren Missouri expects a decision by the MoPSC in the first half of 2026. In February 2026, the MoPSC issued an order approving a nonunanimous stipulation and agreement related to a requested CCN for the Big Hollow Natural Gas (800-MW facility) and the Big Hollow Battery Energy Storage (400-MW facility) projects. Also in February 2026, Ameren Missouri acquired the Split Rail Solar Project, which includes solar panels, project design, land rights, and engineering, procurement, and construction agreements, for approximately $600 million, and took over construction management of the project, which is expected to be placed in-service in the second quarter of 2026.

In February 2026, Ameren Missouri filed an update to its Smart Energy Plan with the MoPSC, which includes a five-year capital investment overview with a detailed one-year plan for 2026. The plan is designed to upgrade Ameren Missouri’s electric infrastructure and includes investments that will upgrade the grid and accommodate more renewable energy. Investments under the plan are expected to total approximately $20.8 billion over the five-year period from 2026 through 2030, with expenditures largely recoverable under the PISA. The Smart Energy Plan excludes investments in its natural gas distribution business, as well as removal costs, net of salvage.

In December 2024, the ICC issued an order in connection with a revised Grid Plan and a revised MYRP filed by Ameren Illinois in March 2024, approving revenue requirements for electric distribution services for 2024 through 2027 of $1,206 million, $1,287 million, $1,367 million, and $1,421 million, respectively. Rate changes consistent with the December 2024 order became effective in December 2024. In March 2025, Ameren Illinois filed an appeal of the ICC’s December 2024 order to the Illinois Appellate Court for the Fifth Judicial District to revise the allowed ROE and to include an asset associated with other postretirement benefits in the rate base, among other things. In addition, Ameren Illinois filed an appeal related to orders issued by the ICC in December 2023 and June 2024 related to the MYRP proceeding. The appellate court is under no deadline to address the appeals.

In December 2025, the ICC issued an order approving Ameren Illinois’ 2024 electric distribution service revenue requirement reconciliation adjustment filing. This order approved an adjustment increasing the allowed revenue requirement by $48 million, which reflected Ameren Illinois’ actual 2024 recoverable costs, year-end rate base of $4.2 billion, and capital structure composed of 50% common equity. The approved reconciliation adjustment will be collected from customers in 2026. In February 2026, the ICC denied Ameren Illinois’ rehearing request to include an asset associated with other postretirement benefits in the rate base, among other things. Ameren Illinois is assessing whether to pursue an appeal with the Illinois Appellate Court for the Fifth Judicial District in the first half of 2026.

In November 2025, the ICC issued an order in Ameren Illinois’ annual update filing that approved an electric customer energy-efficiency revenue requirement of $138 million beginning in January 2026, which represents an increase of $12 million from the 2025 revenue requirement. This order was based on a projected 2026 year-end rate base of $474 million.

In August 2025, the ICC issued an order approving Ameren Illinois’ energy-efficiency plan that includes annual investments in electric energy-efficiency programs of approximately $126 million per year from 2026 through 2029. The ICC has the ability to reduce the amount of electric energy-efficiency savings goals in future program years if there are insufficient cost-effective programs available, which could reduce the investments in electric energy-efficiency programs.

In January 2026, the CRGA was enacted and will become effective in June 2026. The law includes certain provisions that affect Ameren Illinois’ electric distribution and transmission businesses. These provisions increase the annual spending cap on energy-efficiency investments beginning in 2027 and modify the ROE component of the return on those investments.

In November 2025, the ICC issued an order in Ameren Illinois’ January 2025 natural gas delivery service regulatory rate review, which resulted in an increase to its annual revenues for natural gas delivery service of $79 million based on a 9.60% ROE, a capital structure composed of 50% common equity, a 2026 future test year, and a rate base of $3.2 billion. The order reflected a reduction of $75 million of planned distribution and transmission capital investments included in Ameren Illinois’ future test year request. The new rates became effective December 2025. In January 2026, Ameren Illinois filed an appeal of the ICC’s November 2025 order and the ICC’s January 2026 order rejecting Ameren Illinois’ rehearing request to the Illinois Appellate Court for the Fifth Judicial District. The appeal challenged the inclusion of the non-service cost component of the net periodic benefit income related to other postretirement benefits in the annual revenue requirement and the $75 million reduction of planned capital investments, among other things. The court is under no deadline to address the appeal.

In February 2025, Ameren’s board of directors increased the quarterly common stock dividend to 71 cents per share, resulting in an annualized equivalent dividend rate of $2.84 per share. In February 2026, Ameren’s board of directors increased the quarterly common stock dividend to 75 cents per share, resulting in an annualized equivalent dividend rate of $3.00 per share.

For further information on the matters discussed above, see Note 2 – Rate and Regulatory Matters under Part II, Item 8, of this report, and the Outlook section below.

Earnings

Net income attributable to Ameren common shareholders was $1,456 million, or $5.35 per diluted share, for 2025, and $1,182 million, or $4.42 per diluted share, for 2024. Net income was favorably affected in 2025, compared with 2024, by increased base rate revenues at Ameren Missouri effective June 1, 2025, pursuant to the April 2025 MoPSC electric rate order and decreased tax expense at Ameren Transmission, Ameren Illinois Electric Distribution and Ameren Illinois Natural Gas due to the revaluation of excess deferred income tax regulatory liabilities. Earnings were also favorably affected by increased retail electric sales volumes at Ameren Missouri, primarily due to warmer July temperatures and colder winter temperatures in 2025, and by decreased other operations and maintenance expenses not subject to formula rates, riders, or trackers, because of the absence in 2025 of an Ameren Missouri charge related to the resolution of outstanding claims in the NSR and Clean Air Act litigation associated with the Rush Island Energy Center. Additionally, earnings were favorably affected by the increased deferral of financing costs related to rate base investments at Ameren Missouri and by increased infrastructure investments at Ameren Transmission and Ameren Illinois Electric Distribution. Net income was unfavorably affected in 2025 compared with 2024 by increased financing costs, primarily resulting from higher interest rates on higher debt balances at Ameren Missouri and Ameren (parent) and by increased other operations and maintenance expenses not subject to formula rates, riders, or trackers, excluding a charge related to the NSR and Clean Air Act litigation, primarily due to higher vegetation management costs, higher storm costs, and higher energy center maintenance expenses. Additionally, earnings were unfavorably affected by an increase in the weighted-average basic common shares outstanding, which reduced earnings per diluted share.

Liquidity

At December 31, 2025, Ameren, on a consolidated basis, had available liquidity in the form of cash on hand and amounts available under the Credit Agreements of $2.5 billion.

Ameren may offer and sell from time to time common stock, including under its ATM program, which includes the ability to enter into forward sale agreements, subject to market conditions and other factors. As of December 31, 2025, Ameren had approximately $1.5 billion of common stock remaining available for sale under the ATM program. As of December 31, 2025, Ameren had multiple forward sale agreements with various counterparties relating to 6.4 million shares of common stock, which it expects to settle in 2026. For information regarding long-term debt issuances and maturities, common stock issuances, and outstanding forward sale agreements, including those under the ATM program, through the date of this report, see Note 5 – Long-term Debt and Equity Financings under Part II, Item 8, of this report.

Ameren remains focused on strategic capital allocation. The following chart presents 2025 capital expenditures by segment and the midpoint of projected cumulative capital expenditures for 2026 through 2030 by segment:

For 2026 through 2030, Ameren’s cumulative capital expenditures are projected to range from $30.5 billion to $33.1 billion. The following table presents the range of projected spending by segment:

(a)Amounts include investments under Ameren Missouri’s Smart Energy Plan.

(b)Amounts include the MISO long-range transmission projects assigned to Ameren, as well as the first tranche competitive projects awarded to ATXI.