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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM 10-Q

☒ | Quarterly report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 for the Quarterly Period Ended September 30, 2025

OR

☐ | Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 for the transition period from to

Commission File Number | Exact name of registrant as specified in its charter; State of Incorporation; Address and Telephone Number | IRS Employer Identification No.
1-14756 | Ameren Corporation | 43-1723446

(Missouri Corporation)
1901 Chouteau Avenue
St. Louis, Missouri 63103
(314) 621-3222

1-2967 | Union Electric Company | 43-0559760

(Missouri Corporation)
1901 Chouteau Avenue
St. Louis, Missouri 63103
(314) 621-3222

1-3672 | Ameren Illinois Company | 37-0211380

(Illinois Corporation)
10 Richard Mark Way
Collinsville, Illinois 62234
(618) 343-8150
Securities Registered Pursuant to Section 12(b) of the Act:

Title of each class | Trading Symbol(s) | Name of each exchange on which registered
Common Stock, $0.01 par value per share | AEE | New York Stock Exchange

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Indicate 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.

Ameren Corporation |  | Yes |  | ☒ |  | No |  | ☐
Union Electric Company |  | Yes |  | ☒ |  | No |  | ☐
Ameren Illinois Company |  | Yes |  | ☒ |  | No |  | ☐

Indicate 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).

Ameren Corporation |  | Yes |  | ☒ |  | No |  | ☐
Union Electric Company |  | Yes |  | ☒ |  | No |  | ☐
Ameren Illinois Company |  | Yes |  | ☒ |  | No |  | ☐

Indicate 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.

Ameren Corporation | Large accelerated filer | ☒ | Accelerated filer | ☐ | Non-accelerated filer | ☐
|  |  | Smaller reporting company | ☐ | Emerging growth company | ☐
Union Electric Company | Large accelerated filer | ☐ | Accelerated filer | ☐ | Non-accelerated filer | ☒
|  |  | Smaller reporting company | ☐ | Emerging growth company | ☐
Ameren Illinois Company | Large accelerated filer | ☐ | Accelerated filer | ☐ | Non-accelerated filer | ☒
|  |  | Smaller reporting company | ☐ | Emerging growth company | ☐

If 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.

Ameren Corporation | ☐
Union Electric Company | ☐
Ameren Illinois Company | ☐

Indicate by check mark whether each registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).

Ameren Corporation |  | Yes |  | ☐ |  | No |  | ☒
Union Electric Company |  | Yes |  | ☐ |  | No |  | ☒
Ameren Illinois Company |  | Yes |  | ☐ |  | No |  | ☒

The number of shares outstanding of each registrant’s classes of common stock as of October 31, 2025, was as follows:

Registrant |  | Title of each class of common stock | Shares outstanding
Ameren Corporation |  | Common stock, $0.01 par value per share | 270,494,916 |
Union Electric Company |  | Common stock, $5 par value per share, held by Ameren Corporation | 102,123,834 |
Ameren Illinois Company |  | Common stock, no par value, held by Ameren Corporation | 25,452,373 |

This 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.

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|  | Page
Glossary of Terms and Abbreviations | 1
Forward-looking Statements | 1
PART I. Financial Information |
Item 1. | Financial Statements (Unaudited) | 4
| Ameren Corporation | 4
| Consolidated Statement of Income and Comprehensive Income | 4
| Consolidated Balance Sheet | 5
| Consolidated Statement of Cash Flows | 6
| Consolidated Statement of Shareholders’ Equity | 7
| Union Electric Company (d/b/a Ameren Missouri) | 8
| Consolidated Statement of Income | 8
| Consolidated Balance Sheet | 9
| Consolidated Statement of Cash Flows | 10
| Consolidated Statement of Shareholders’ Equity | 11
| Ameren Illinois Company (d/b/a Ameren Illinois) | 12
| Statement of Income | 12
| Balance Sheet | 13
| Statement of Cash Flows | 14
| Statement of Shareholders’ Equity | 15
| Note 1. Summary of Significant Accounting Policies | 16
| Note 2. Rate and Regulatory Matters | 17
| Note 3. Short-term Debt and Liquidity | 21
| Note 4. Long-term Debt and Equity Financings | 22
| Note 5. Other Income, Net | 23
| Note 6. Derivative Financial Instruments | 24
| Note 7. Fair Value Measurements | 25
| Note 8. Related-party Transactions | 28
| Note 9. Commitments and Contingencies | 29
| Note 10. Callaway Energy Center | 31
| Note 11. Retirement Benefits | 32
| Note 12. Income Taxes | 33
| Note 13. Supplemental Information | 34
| Note 14. Segment Information | 37
Item 2. | Management’s Discussion and Analysis of Financial Condition and Results of Operations | 44
Item 3. | Quantitative and Qualitative Disclosures About Market Risk | 79
Item 4. | Controls and Procedures | 79
PART II. Other Information |
Item 1. | Legal Proceedings | 79
Item 1A. | Risk Factors | 80
Item 2. | Unregistered Sales of Equity Securities and Use of Proceeds | 80
Item 5. | Other Information | 80
Item 6. | Exhibits | 81
Signatures | 82

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GLOSSARY OF TERMS AND ABBREVIATIONS
We use the words “our,” “we” or “us” with respect to certain information that relates to Ameren, Ameren Missouri, and Ameren Illinois, collectively. When appropriate, subsidiaries of Ameren Corporation are named specifically as their various business activities are discussed. Refer to the Form 10-K for a complete listing of glossary terms and abbreviations. Only new or significantly changed terms and abbreviations are included below.
2023 PRP – Preferred Resource Plan, Ameren Missouri’s preferred plan for meeting customers’ projected long-term energy needs, which was filed with the MoPSC in September 2023 as a part of its integrated resource plan.
2025 Change to the 2023 PRP – A change to Ameren Missouri’s 2023 PRP filed with the MoPSC in February 2025 reflecting certain modifications to Ameren Missouri’s preferred plan for meeting customers’ projected long-term energy needs.
Form 10-K – The combined Annual Report on Form 10-K for the year ended December 31, 2024, filed by the Ameren Companies with the SEC.
OBBBA – The One Big Beautiful Bill Act, federal legislation enacted in July 2025.
QTD – Three months ended September 30.
YTD – Nine months ended September 30.
YoY – Compared with the year-ago period.
FORWARD-LOOKING STATEMENTS
Statements in this report not based on historical facts are considered “forward-looking” and, accordingly, involve risks and uncertainties that could cause actual results to differ materially from those discussed. Although such forward-looking statements have been made in good faith and are based on reasonable assumptions, there is no assurance that the expected results will be achieved. These statements include (without limitation) statements as to future expectations, beliefs, plans, projections, strategies, targets, estimates, objectives, events, conditions, and financial performance. In connection with the “safe harbor” provisions of the Private Securities Litigation Reform Act of 1995, we are providing this cautionary statement to identify important factors that could cause actual results to differ materially from those anticipated. The following factors, in addition to those discussed within Risk Factors in the Form 10-K, and elsewhere in this report and in our other filings with the SEC, could cause actual results to differ materially from management expectations suggested in such forward-looking statements:
•regulatory, judicial, or legislative actions, and any changes in regulatory policies and ratemaking determinations that may change regulatory recovery mechanisms, such as those that may result from Ameren Missouri’s request with the MoPSC to modify its existing large primary service tariff, Ameren Illinois’ appeal of the December 2023 and 2024 ICC orders for the MYRP electric distribution service regulatory rate review and June 2024 rehearing order to the Illinois Appellate Court for the Fifth Judicial District, Ameren Illinois’ electric distribution service revenue requirement reconciliation adjustment request filed with the ICC in April 2025, Ameren Illinois’ natural gas delivery service regulatory rate review filed with the ICC in January 2025, and the January and April 2025 appeals of FERC’s October 2024 and March 2025 orders by the MISO transmission owners, including Ameren Missouri, Ameren Illinois, and ATXI;
•our ability to control costs and make substantial investments in our businesses, including our ability to recover costs and investments, and to earn our allowed ROEs, within frameworks established by our regulators, while maintaining affordability of services for our customers;
•the effect and duration of Ameren Illinois’ election to utilize MYRPs for electric distribution service ratemaking effective for rates beginning in 2024, including the effect of the reconciliation cap on the electric distribution revenue requirement;
•the effect of Ameren Illinois’ use of the performance-based formula ratemaking framework for its participation in electric energy-efficiency programs, and the related impact of the direct relationship between Ameren Illinois’ ROE and the 30-year United States Treasury bond yields;
•the effect on Ameren Missouri of any customer rate caps or limitations on increasing the electric service revenue requirement pursuant to Ameren Missouri’s election to use the PISA;
•Ameren Missouri’s ability to construct and/or acquire wind, solar, and other renewable energy generation facilities and battery storage, as well as natural gas-fired and nuclear energy centers, extend the operating license for the Callaway Energy Center, retire fossil fuel-fired energy centers, and implement new or existing customer energy-efficiency programs, including any such construction, acquisition, retirement, or implementation in connection with its Smart Energy Plan, preferred resource plan, or emissions reduction goals, and to recover its cost of investment, a related return, and, in the case of customer energy-efficiency programs, any lost electric revenues in a timely manner, each of which is affected by the ability to obtain all necessary regulatory and project approvals, including CCNs from the MoPSC or any other required approvals;
•Ameren Missouri’s ability to earn, utilize, or transfer at a reasonable price federal production and investment tax credits related to renewable energy projects and nuclear energy production; the cost of wind, solar, and other renewable generation and battery storage technologies; and our ability to obtain timely interconnection agreements with the MISO or other RTOs at an acceptable cost for each facility;
1

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•the outcome of the MISO long-range transmission planning process, including changes to planned projects, the ability to secure competitively bid or assigned projects and related approvals, including CCNs from the MoPSC and ICC or any other required approvals, and changes in applicable legislative or regulatory frameworks;
•the inability of our counterparties to meet their obligations with respect to contracts, credit agreements, and financial instruments, including as they relate to the construction and acquisition of electric and natural gas utility infrastructure and the ability of counterparties to complete projects, which is dependent upon the availability of necessary materials and equipment, including those obligations that are affected by supply chain disruptions;
•advancements in energy technologies, including carbon capture, utilization, and sequestration, hydrogen fuel for electric production and energy storage, next generation nuclear, and large-scale long-cycle battery energy storage, and the impact of federal and state energy and economic policies with respect to those technologies;
•the effects of changes in federal, state, or local laws and other domestic or international governmental actions, including monetary, fiscal, foreign trade, and energy policies, foreign trade tariffs, executive orders, or extended federal government shutdowns or defunding;
•the effects of changes in federal, state, or local tax laws or rates; additional regulations, interpretations, amendments, or technical corrections to, or in connection with the OBBBA and the IRA, including the effects of the OBBBA as it relates to construction timelines of solar and wind projects along with the ability to obtain materials for these projects to be eligible for federal production and investment tax credits, and the effects of the IRA as it relates to the 15% minimum tax on adjusted financial statement income; and any challenges to the tax positions taken by the Ameren Companies, as well as resulting effects on customer rates and the recoverability of the minimum tax imposed under the IRA;
•our ability to realize forecasted energy demand from potential new customers, including demand growth dependent on the addition of new data centers and other large primary service customers within our service territories;
•the effects on energy prices and demand for our services resulting from customer growth patterns or usage, including demand from data centers, technological advances, including advances in customer energy efficiency, electric vehicles, electrification of various industries, energy storage, and private generation sources, which generate electricity at the site of consumption and are becoming increasingly cost-competitive;
•the cost and availability of fuel, such as low-sulfur coal, natural gas, and enriched uranium used to produce electricity; the cost and availability of natural gas for distribution and the cost and availability of purchased power, including capacity, zero emission credits, renewable energy credits, and emission allowances; and the level and volatility of future market prices for such commodities and credits;
•disruptions in the delivery of fuel, failure of our fuel suppliers to provide adequate quantities or quality of fuel, or lack of adequate inventories of fuel, including nuclear fuel assemblies primarily from the one NRC-licensed supplier of assemblies for Ameren Missouri’s Callaway Energy Center;
•the cost and availability of transmission capacity required for the energy generated by Ameren Missouri’s energy centers or as required to satisfy our energy sales;
•the effectiveness of our risk management strategies and our use of financial and derivative instruments;
•the ability to obtain sufficient insurance, or, in the absence of insurance, the ability to timely recover uninsured losses from our customers;
•the impact of cyberattacks and data security risks on us, our suppliers, or other entities on the grid, which could, among other things, result in the loss of operational control of energy centers and electric and natural gas transmission and distribution systems and/or the loss of data, such as customer, employee, financial, and operating system information;
•acts of sabotage, which have increased in frequency and severity within the utility industry, war, terrorism, or other intentionally disruptive acts;
•business, economic, geopolitical, and capital market conditions, including foreign trade tariffs or trade wars, evolving federal regulatory priorities, and the impact of such conditions on interest rates, inflation, and investments;
•the impact of inflation or a recession on our customers and suppliers and the related impact on our results of operations, financial position, and liquidity;
•disruptions of the capital and credit markets, deterioration in credit metrics of the Ameren Companies, or other events that may have an adverse effect on the cost or availability of capital, including short-term credit and liquidity, and our ability to access the capital and credit markets on reasonable terms when needed;
•the actions of credit rating agencies and the effects of such actions;
•the impact of weather conditions and other natural conditions on us and our customers, including the impact of system outages and the level of wind and solar resources;
•the construction, installation, performance, and cost recovery of generation, transmission, and distribution assets;
•the ability to maintain system reliability during and after the transition to clean energy generation by Ameren Missouri and the electric utility industry, as well as Ameren Missouri’s ability to meet existing or future generation capacity obligations;
•the effects of failures of electric generation, electric and natural gas transmission or distribution, or natural gas storage facilities systems and equipment, which could result in unanticipated liabilities or unplanned outages;
•the operation of Ameren Missouri’s Callaway Energy Center, including planned and unplanned outages, as well as the ability to recover costs associated with such outages and the impact of such outages on off-system sales and purchased power, among other things;
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•Ameren Missouri’s ability to recover the remaining investment and decommissioning costs associated with the retirement of an energy center, as well as the ability to earn a return on that remaining investment and those decommissioning costs;
•the impact of current environmental laws or their interpretation and new, more stringent, or changing requirements and environmental policies, including those related to NSR, CO 2, NO x, SO 2, and other emissions and discharges, Illinois emission standards, cooling water intake structures, CCR, energy efficiency, and wildlife protection, that could limit, terminate or otherwise modify the operation of certain of Ameren Missouri’s energy centers, increase our operating costs or investment requirements, result in an impairment of our assets, cause us to sell our assets, reduce our customers’ demand for electricity or natural gas, or otherwise have a negative financial effect;
•the impact of complying with renewable energy standards in Missouri and Illinois and with the zero emission standard in Illinois;
•the effectiveness of Ameren Missouri’s customer energy-efficiency programs and the related revenues and performance incentives earned under its MEEIA programs;
•Ameren Illinois’ ability to achieve the performance standards applicable to its electric distribution business and electric customer energy-efficiency goals and the resulting impact on its allowed ROE;
•labor disputes, workforce reductions, our ability to attract and retain professional and skilled-craft employees, changes in future wage and employee benefits costs, including those resulting from changes in discount rates, mortality tables, returns on benefit plan assets, and other assumptions;
•the impact of negative opinions of us or our utility services that our customers, investors, legislators, regulators, creditors, rating agencies, or other stakeholders may have or develop, which could result from a variety of factors, including failures in system reliability, failure to implement our investment plans or to protect sensitive customer information, increases in rates, negative media coverage, or concerns about company policies or practices;
•the impact of adopting new accounting and reporting guidance;
•the effects of strategic initiatives, including mergers, acquisitions, and divestitures;
•legal and administrative proceedings;
•pandemics or other significant global health events, and their impacts on our results of operations, financial position, and liquidity; and
•the impacts of the Russian invasion of Ukraine and conflicts in the Middle East, related sanctions imposed by the United States and other governments, and any broadening of these or other global conflicts, including potential impacts on the cost and availability of fuel, natural gas, enriched uranium, and other commodities, materials, and services.
New factors emerge from time to time, and it is not possible for management to predict all of such factors, nor can it assess the impact of each such factor on the business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained or implied in any forward-looking statement. Given these uncertainties, undue reliance should not be placed on these forward-looking statements. Except to the extent required by the federal securities laws, we undertake no obligation to update or revise publicly any forward-looking statements to reflect new information or future events.
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PART I. FINANCIAL INFORMATION
ITEM 1. FINANCIAL STATEMENTS.
AMEREN CORPORATION
CONSOLIDATED STATEMENT OF INCOME AND COMPREHENSIVE INCOME
(Unaudited) (In millions, except per share amounts)

| Three Months Ended September 30, |  | Nine Months Ended September 30,
| 2025 |  | 2024 |  | 2025 |  | 2024
Operating Revenues: |  |  |  |  |  |  |
Electric | $ | 2,563 |  |  | $ | 2,035 |  |  | $ | 6,223 |  |  | $ | 4,920 |
Natural gas | 136 |  |  | 138 |  |  | 794 |  |  | 762 |
Total operating revenues | 2,699 |  |  | 2,173 |  |  | 7,017 |  |  | 5,682 |
Operating Expenses: |  |  |  |  |  |  |
Fuel and purchased power | 768 |  |  | 499 |  |  | 2,064 |  |  | 1,154 |
Natural gas purchased for resale | 25 |  |  | 30 |  |  | 233 |  |  | 214 |
Other operations and maintenance | 502 |  |  | 520 |  |  | 1,447 |  |  | 1,455 |
Depreciation and amortization | 415 |  |  | 388 |  |  | 1,168 |  |  | 1,125 |
Taxes other than income taxes | 164 |  |  | 150 |  |  | 439 |  |  | 416 |
Total operating expenses | 1,874 |  |  | 1,587 |  |  | 5,351 |  |  | 4,364 |
Operating Income | 825 |  |  | 586 |  |  | 1,666 |  |  | 1,318 |
Other Income, Net | 76 |  |  | 101 |  |  | 257 |  |  | 293 |
Interest Charges | 208 |  |  | 173 |  |  | 570 |  |  | 492 |
Income Before Income Taxes | 693 |  |  | 514 |  |  | 1,353 |  |  | 1,119 |
Income Taxes | 52 |  |  | 57 |  |  | 145 |  |  | 140 |
Net Income | 641 |  |  | 457 |  |  | 1,208 |  |  | 979 |
Less: Net Income Attributable to Noncontrolling Interests | 1 |  |  | 1 |  |  | 4 |  |  | 4 |
Net Income Attributable to Ameren Common Shareholders | $ | 640 |  |  | $ | 456 |  |  | $ | 1,204 |  |  | $ | 975 |
Net Income | $ | 641 |  |  | $ | 457 |  |  | $ | 1,208 |  |  | $ | 979 |
Other Comprehensive Income (Loss), Net of Taxes |  |  |  |  |  |  |
Pension and other postretirement benefit plan activity, net of income taxes (benefit) of $—, $—, $(1), and $(1) respectively | — |  |  | (1) |  |  | (2) |  |  | (4) |
Unrealized net loss on derivative hedging instruments, net of income taxes (benefit) of $—, $—, $(1), and $—, respectively | — |  |  | — |  |  | (6) |  |  | — |
Comprehensive Income | 641 |  |  | 456 |  |  | 1,200 |  |  | 975 |
Less: Comprehensive Income Attributable to Noncontrolling Interests | 1 |  |  | 1 |  |  | 4 |  |  | 4 |
Comprehensive Income Attributable to Ameren Common Shareholders | $ | 640 |  |  | $ | 455 |  |  | $ | 1,196 |  |  | $ | 971 |
Earnings per Common Share - Basic | $ | 2.37 |  |  | $ | 1.71 |  |  | $ | 4.46 |  |  | $ | 3.66 |
Earnings per Common Share – Diluted | $ | 2.35 |  |  | $ | 1.70 |  |  | $ | 4.43 |  |  | $ | 3.65 |
Weighted-average Common Shares Outstanding – Basic | 270.4 |  |  | 266.8 |  |  | 270.2 |  |  | 266.6 |
Weighted-average Common Shares Outstanding – Diluted | 272.2 |  |  | 267.3 |  |  | 271.7 |  |  | 266.9 |

The accompanying notes are an integral part of these consolidated financial statements.
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AMEREN CORPORATION
CONSOLIDATED BALANCE SHEET
(Unaudited) (In millions, except per share amounts)

| September 30, 2025 |  | December 31, 2024
ASSETS |  |  |
Current Assets: |  |  |
Cash and cash equivalents | $ | 9 |  |  | $ | 7 |
Accounts receivable – trade (less allowance for doubtful accounts of $38 and $30, respectively) | 794 |  |  | 525 |
Unbilled revenue | 413 |  |  | 346 |
Miscellaneous accounts receivable | 78 |  |  | 96 |
Inventories | 804 |  |  | 762 |
Current regulatory assets | 260 |  |  | 366 |
Other current assets (includes $46 and $2 related to VIEs, respectively) | 252 |  |  | 162 |
Total current assets | 2,610 |  |  | 2,264 |
Property, Plant, and Equipment, Net | 38,411 |  |  | 36,304 |
Investments and Other Assets: |  |  |
Nuclear decommissioning trust fund | 1,502 |  |  | 1,342 |
Goodwill | 411 |  |  | 411 |
Regulatory assets (includes $449 and $465 related to VIEs, respectively) | 2,611 |  |  | 2,397 |
Pension and other postretirement benefits | 741 |  |  | 757 |
Other assets | 1,130 |  |  | 1,123 |
Total investments and other assets | 6,395 |  |  | 6,030 |
TOTAL ASSETS | $ | 47,416 |  |  | $ | 44,598 |
LIABILITIES AND EQUITY |  |  |
Current Liabilities: |  |  |
Current maturities of long-term debt (includes $29 and $17 related to VIEs, respectively) | $ | 29 |  |  | $ | 317 |
Short-term debt | 903 |  |  | 1,143 |
Accounts and wages payable | 762 |  |  | 1,059 |
Taxes accrued | 215 |  |  | 60 |
Interest accrued | 183 |  |  | 196 |
Customer deposits | 248 |  |  | 223 |
Current regulatory liabilities | 142 |  |  | 120 |
Other current liabilities | 323 |  |  | 295 |
Total current liabilities | 2,805 |  |  | 3,413 |
Long-term Debt, Net (includes $437 and $448 related to VIEs, respectively) | 19,172 |  |  | 17,262 |
Deferred Credits and Other Liabilities: |  |  |
Accumulated deferred income taxes and tax credits, net | 5,081 |  |  | 4,474 |
Regulatory liabilities | 6,089 |  |  | 5,897 |
Asset retirement obligations | 844 |  |  | 822 |
Other deferred credits and liabilities | 516 |  |  | 487 |
Total deferred credits and other liabilities | 12,530 |  |  | 11,680 |
Commitments and Contingencies (Notes 2, 9, and 10) |  |  |
Shareholders’ Equity: |  |  |
Common stock, $.01 par value, 400.0 shares authorized – shares outstanding of 270.5 and 269.9, respectively | 3 |  |  | 3 |
Other paid-in capital, principally premium on common stock | 7,559 |  |  | 7,513 |
Retained earnings | 5,232 |  |  | 4,604 |
Accumulated other comprehensive loss | (14) |  |  | (6) |
Total shareholders’ equity | 12,780 |  |  | 12,114 |
Noncontrolling Interests | 129 |  |  | 129 |
Total equity | 12,909 |  |  | 12,243 |
TOTAL LIABILITIES AND EQUITY | $ | 47,416 |  |  | $ | 44,598 |

The accompanying notes are an integral part of these consolidated financial statements.
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AMEREN CORPORATION
CONSOLIDATED STATEMENT OF CASH FLOWS
(Unaudited) (In millions)
| Nine Months Ended September 30,
| 2025 |  | 2024
Cash Flows From Operating Activities: |  |  |
Net income | $ | 1,208 |  |  | $ | 979 |
Adjustments to reconcile net income to net cash provided by operating activities: |  |  |
Depreciation and amortization | 1,199 |  |  | 1,142 |
Amortization of nuclear fuel | 39 |  |  | 59 |
Amortization of debt issuance costs and premium/discounts | 14 |  |  | 14 |
Deferred income taxes and tax credits, net | 255 |  |  | 145 |
Allowance for equity funds used during construction | (60) |  |  | (48) |
Stock-based compensation costs | 21 |  |  | 22 |
Other | 29 |  |  | 84 |
Changes in assets and liabilities: |  |  |
Receivables | (356) |  |  | (183) |
Inventories | (41) |  |  | (60) |
Accounts and wages payable | (244) |  |  | (239) |
Taxes accrued | 307 |  |  | 176 |
Regulatory assets and liabilities | 97 |  |  | 86 |
Assets, other | (29) |  |  | (59) |
Liabilities, other | 72 |  |  | (4) |
Pension and other postretirement benefits | (114) |  |  | (168) |
Net cash provided by operating activities | 2,397 |  |  | 1,946 |
Cash Flows From Investing Activities: |  |  |
Capital expenditures | (3,118) |  |  | (3,029) |
Nuclear fuel expenditures | (20) |  |  | (57) |
Purchases of securities – nuclear decommissioning trust fund | (373) |  |  | (499) |
Sales and maturities of securities – nuclear decommissioning trust fund | 348 |  |  | 480 |
Other | 51 |  |  | (1) |
Net cash used in investing activities | (3,112) |  |  | (3,106) |
Cash Flows From Financing Activities: |  |  |
Dividends on common stock | (576) |  |  | (535) |
Dividends paid to noncontrolling interest holders | (4) |  |  | (4) |
Short-term debt, net | (239) |  |  | 1,002 |
Maturities and extinguishment of long-term debt | (324) |  |  | (849) |
Issuances of long-term debt | 1,960 |  |  | 1,610 |
Issuances of common stock | 35 |  |  | 30 |
Employee payroll taxes related to stock-based compensation | (13) |  |  | (8) |
Debt issuance costs | (17) |  |  | (19) |
Other | — |  |  | (15) |
Net cash provided by financing activities | 822 |  |  | 1,212 |
Net change in cash, cash equivalents, and restricted cash | 107 |  |  | 52 |
Cash, cash equivalents, and restricted cash at beginning of year | 328 |  |  | 272 |
Cash, cash equivalents, and restricted cash at end of period | $ | 435 |  |  | $ | 324 |

The accompanying notes are an integral part of these consolidated financial statements.
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AMEREN CORPORATION
CONSOLIDATED STATEMENT OF SHAREHOLDERS’ EQUITY
(Unaudited) (In millions, except per share amounts)

| Three Months Ended September 30, |  | Nine Months Ended September 30,
| 2025 |  | 2024 |  | 2025 |  | 2024
Common Stock | $ | 3 |  |  | $ | 3 |  |  | $ | 3 |  |  | $ | 3 |
Other Paid-in Capital: |  |  |  |  |  |  |
Beginning of period | 7,541 |  |  | 7,246 |  |  | 7,513 |  |  | 7,216 |
Shares issued under the DRPlus and 401(k) plan | 10 |  |  | 9 |  |  | 35 |  |  | 30 |
Stock-based compensation activity | 8 |  |  | 9 |  |  | 11 |  |  | 18 |
Other paid-in capital, end of period | 7,559 |  |  | 7,264 |  |  | 7,559 |  |  | 7,264 |
Retained Earnings: |  |  |  |  |  |  |
Beginning of period | 4,784 |  |  | 4,299 |  |  | 4,604 |  |  | 4,136 |
Net income attributable to Ameren common shareholders | 640 |  |  | 456 |  |  | 1,204 |  |  | 975 |
Dividends on common stock | (192) |  |  | (179) |  |  | (576) |  |  | (535) |
Retained earnings, end of period | 5,232 |  |  | 4,576 |  |  | 5,232 |  |  | 4,576 |
Accumulated Other Comprehensive Loss: |  |  |  |  |  |  |
Derivative financial instruments, beginning of period | (3) |  |  | — |  |  | 3 |  |  | — |
Change in derivative financial instruments | — |  |  | — |  |  | (6) |  |  | — |
Derivative financial instruments, end of period | (3) |  |  | — |  |  | (3) |  |  | — |
Deferred retirement benefit costs, beginning of period | (11) |  |  | (9) |  |  | (9) |  |  | (6) |
Change in deferred retirement benefit costs | — |  |  | (1) |  |  | (2) |  |  | (4) |
Deferred retirement benefit costs, end of period | (11) |  |  | (10) |  |  | (11) |  |  | (10) |
Total accumulated other comprehensive loss, end of period | (14) |  |  | (10) |  |  | (14) |  |  | (10) |
Total Shareholders’ Equity | $ | 12,780 |  |  | $ | 11,833 |  |  | $ | 12,780 |  |  | $ | 11,833 |
Noncontrolling Interests: |  |  |  |  |  |  |
Beginning of period | 129 |  |  | 129 |  |  | 129 |  |  | 129 |
Net income attributable to noncontrolling interest holders | 1 |  |  | 1 |  |  | 4 |  |  | 4 |
Dividends paid to noncontrolling interest holders | (1) |  |  | (1) |  |  | (4) |  |  | (4) |
Noncontrolling interests, end of period | 129 |  |  | 129 |  |  | 129 |  |  | 129 |
Total Equity | $ | 12,909 |  |  | $ | 11,962 |  |  | $ | 12,909 |  |  | $ | 11,962 |
Common stock shares outstanding at beginning of period | 270.4 |  |  | 266.8 |  |  | 269.9 |  |  | 266.3 |
Shares issued under the DRPlus and 401(k) plan | 0.1 |  |  | 0.1 |  |  | 0.3 |  |  | 0.4 |
Shares issued for stock-based compensation | — |  |  | — |  |  | 0.3 |  |  | 0.2 |
Common stock shares outstanding at end of period | 270.5 |  |  | 266.9 |  |  | 270.5 |  |  | 266.9 |
Dividends per common share | $ | 0.71 |  |  | $ | 0.67 |  |  | $ | 2.13 |  |  | $ | 2.01 |

The accompanying notes are an integral part of these consolidated financial statements.
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UNION ELECTRIC COMPANY (d/b/a AMEREN MISSOURI)
CONSOLIDATED STATEMENT OF INCOME
(Unaudited) (In millions)

| Three Months Ended September 30, |  | Nine Months Ended September 30,
| 2025 |  | 2024 |  | 2025 |  | 2024
Operating Revenues: |  |  |  |  |  |  |
Electric | $ | 1,685 |  |  | $ | 1,324 |  |  | $ | 3,893 |  |  | $ | 2,902 |
Natural gas | 20 |  |  | 18 |  |  | 109 |  |  | 103 |
Total operating revenues | 1,705 |  |  | 1,342 |  |  | 4,002 |  |  | 3,005 |
Operating Expenses: |  |  |  |  |  |  |
Fuel and purchased power | 487 |  |  | 334 |  |  | 1,431 |  |  | 689 |
Natural gas purchased for resale | 6 |  |  | 4 |  |  | 45 |  |  | 41 |
Other operations and maintenance | 260 |  |  | 288 |  |  | 748 |  |  | 789 |
Depreciation and amortization | 239 |  |  | 220 |  |  | 642 |  |  | 623 |
Taxes other than income taxes | 122 |  |  | 109 |  |  | 300 |  |  | 287 |
Total operating expenses | 1,114 |  |  | 955 |  |  | 3,166 |  |  | 2,429 |
Operating Income | 591 |  |  | 387 |  |  | 836 |  |  | 576 |
Other Income, Net | 45 |  |  | 51 |  |  | 135 |  |  | 144 |
Interest Charges | 85 |  |  | 62 |  |  | 215 |  |  | 187 |
Income Before Income Taxes | 551 |  |  | 376 |  |  | 756 |  |  | 533 |
Income Taxes (Benefit) | 32 |  |  | (6) |  |  | 43 |  |  | (4) |
Net Income | 519 |  |  | 382 |  |  | 713 |  |  | 537 |
Preferred Stock Dividends | 1 |  |  | 1 |  |  | 3 |  |  | 3 |
Net Income Available to Common Shareholder | $ | 518 |  |  | $ | 381 |  |  | $ | 710 |  |  | $ | 534 |

The accompanying notes as they relate to Ameren Missouri are an integral part of these consolidated financial statements.
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UNION ELECTRIC COMPANY (d/b/a AMEREN MISSOURI)
CONSOLIDATED BALANCE SHEET
(Unaudited) (In millions, except per share amounts)

| September 30, 2025 |  | December 31, 2024
ASSETS |  |  |
Current Assets: |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |
Restricted cash (includes $46 and $2 related to VIEs, respectively) | 86 |  |  | 7 |
Advances to money pool | — |  |  | 43 |
Accounts receivable – trade (less allowance for doubtful accounts of $15 and $12, respectively) | 359 |  |  | 209 |
Accounts receivable – affiliates | 24 |  |  | 40 |
Unbilled revenue | 267 |  |  | 170 |
Miscellaneous accounts receivable | 9 |  |  | 33 |
Inventories | 511 |  |  | 514 |
Current regulatory assets | 149 |  |  | 66 |
Other current assets | 70 |  |  | 63 |
Total current assets | 1,475 |  |  | 1,145 |
Property, Plant, and Equipment, Net | 20,083 |  |  | 18,788 |
Investments and Other Assets: |  |  |
Nuclear decommissioning trust fund | 1,502 |  |  | 1,342 |
Regulatory assets (includes $449 and $465 related to VIEs, respectively) | 1,454 |  |  | 1,366 |
Pension and other postretirement benefits | 202 |  |  | 211 |
Other assets | 235 |  |  | 254 |
Total investments and other assets | 3,393 |  |  | 3,173 |
TOTAL ASSETS | $ | 24,951 |  |  | $ | 23,106 |
LIABILITIES AND SHAREHOLDERS’ EQUITY |  |  |
Current Liabilities: |  |  |
Current maturities of long-term debt (includes $29 and $17 related to VIEs, respectively) | $ | 29 |  |  | $ | 17 |
Short-term debt | 259 |  |  | — |
Borrowings from money pool | 51 |  |  | — |
Accounts and wages payable | 355 |  |  | 629 |
Accounts payable – affiliates | 80 |  |  | 50 |
Taxes accrued | 192 |  |  | 29 |
Interest accrued | 94 |  |  | 88 |
Other current liabilities | 204 |  |  | 206 |
Total current liabilities | 1,264 |  |  | 1,019 |
Long-term Debt, Net (includes $437 and $448 related to VIEs, respectively) | 8,130 |  |  | 7,671 |
Long-term Debt, Net - Related Parties | 87 |  |  | 57 |
Deferred Credits and Other Liabilities: |  |  |
Accumulated deferred income taxes and tax credits, net | 2,622 |  |  | 2,217 |
Regulatory liabilities | 3,260 |  |  | 3,176 |
Asset retirement obligations | 839 |  |  | 818 |
Other deferred credits and liabilities | 166 |  |  | 150 |
Total deferred credits and other liabilities | 6,887 |  |  | 6,361 |
Commitments and Contingencies (Notes 2, 8, 9, and 10) |  |  |
Shareholders’ Equity: |  |  |
Common stock, $5 par value, 150.0 shares authorized – 102.1 shares outstanding | 511 |  |  | 511 |
Other paid-in capital, principally premium on common stock | 3,201 |  |  | 3,201 |
Preferred stock | 80 |  |  | 80 |
Retained earnings | 4,791 |  |  | 4,206 |
Total shareholders’ equity | 8,583 |  |  | 7,998 |
TOTAL LIABILITIES AND SHAREHOLDERS’ EQUITY | $ | 24,951 |  |  | $ | 23,106 |

The accompanying notes as they relate to Ameren Missouri are an integral part of these consolidated financial statements.
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UNION ELECTRIC COMPANY (d/b/a AMEREN MISSOURI)
CONSOLIDATED STATEMENT OF CASH FLOWS
(Unaudited) (In millions)

| Nine Months Ended September 30,
| 2025 |  | 2024
Cash Flows From Operating Activities: |  |  |
Net income | $ | 713 |  |  | $ | 537 |
Adjustments to reconcile net income to net cash provided by operating activities: |  |  |
Depreciation and amortization | 673 |  |  | 641 |
Amortization of nuclear fuel | 39 |  |  | 59 |
Amortization of debt issuance costs and premium/discounts | 7 |  |  | 5 |
Deferred income taxes and tax credits, net | 167 |  |  | 2 |
Allowance for equity funds used during construction | (37) |  |  | (38) |
Other | 7 |  |  | 69 |
Changes in assets and liabilities: |  |  |
Receivables | (245) |  |  | (178) |
Inventories | 3 |  |  | (21) |
Accounts and wages payable | (240) |  |  | (223) |
Taxes accrued | 336 |  |  | 218 |
Regulatory assets and liabilities | (155) |  |  | (5) |
Assets, other | 21 |  |  | (20) |
Liabilities, other | 26 |  |  | 10 |
Pension and other postretirement benefits | (42) |  |  | (59) |
Net cash provided by operating activities | 1,273 |  |  | 997 |
Cash Flows From Investing Activities: |  |  |
Capital expenditures | (1,873) |  |  | (1,839) |
Nuclear fuel expenditures | (20) |  |  | (57) |
Purchases of securities – nuclear decommissioning trust fund | (373) |  |  | (499) |
Sales and maturities of securities – nuclear decommissioning trust fund | 348 |  |  | 480 |
Money pool advances, net | 43 |  |  | (9) |
Other | — |  |  | (8) |
Net cash used in investing activities | (1,875) |  |  | (1,932) |
Cash Flows From Financing Activities: |  |  |
Dividends on common stock | (125) |  |  | — |
Dividends on preferred stock | (3) |  |  | (3) |
Short-term debt, net | 259 |  |  | 406 |
Money pool borrowings, net | 51 |  |  | (289) |
Maturities of long-term debt | — |  |  | (350) |
Issuances of long-term debt | 500 |  |  | 846 |
Capital contribution from parent | — |  |  | 350 |
Debt issuance costs | (4) |  |  | (10) |
Other | — |  |  | (15) |
Net cash provided by financing activities | 678 |  |  | 935 |
Net change in cash, cash equivalents, and restricted cash | 76 |  |  | — |
Cash, cash equivalents, and restricted cash at beginning of year | 17 |  |  | 10 |
Cash, cash equivalents, and restricted cash at end of period | $ | 93 |  |  | $ | 10 |

The accompanying notes as they relate to Ameren Missouri are an integral part of these consolidated financial statements.
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UNION ELECTRIC COMPANY (d/b/a AMEREN MISSOURI)
CONSOLIDATED STATEMENT OF SHAREHOLDERS’ EQUITY
(Unaudited) (In millions)

| Three Months Ended September 30, |  | Nine Months Ended September 30,
| 2025 |  | 2024 |  | 2025 |  | 2024
Common Stock | $ | 511 |  |  | $ | 511 |  |  | $ | 511 |  |  | $ | 511 |
Other Paid-in Capital |  |  |  |  |  |  |
Beginning of period | 3,201 |  |  | 3,075 |  |  | 3,201 |  |  | 2,725 |
Capital contributions from parent | — |  |  | — |  |  | — |  |  | 350 |
Other paid-in capital, end of period | 3,201 |  |  | 3,075 |  |  | 3,201 |  |  | 3,075 |
Preferred Stock | 80 |  |  | 80 |  |  | 80 |  |  | 80 |
Retained Earnings: |  |  |  |  |  |  |
Beginning of period | 4,348 |  |  | 3,800 |  |  | 4,206 |  |  | 3,647 |
Net income | 519 |  |  | 382 |  |  | 713 |  |  | 537 |
Dividends on common stock | (75) |  |  | — |  |  | (125) |  |  | — |
Dividends on preferred stock | (1) |  |  | (1) |  |  | (3) |  |  | (3) |
Retained earnings, end of period | 4,791 |  |  | 4,181 |  |  | 4,791 |  |  | 4,181 |
Total Shareholders’ Equity | $ | 8,583 |  |  | $ | 7,847 |  |  | $ | 8,583 |  |  | $ | 7,847 |

The accompanying notes as they relate to Ameren Missouri are an integral part of these consolidated financial statements.
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AMEREN ILLINOIS COMPANY (d/b/a AMEREN ILLINOIS)
STATEMENT OF INCOME
(Unaudited) (In millions)

| Three Months Ended September 30, |  | Nine Months Ended September 30,
| 2025 |  | 2024 |  | 2025 |  | 2024
Operating Revenues: |  |  |  |  |  |  |
Electric | $ | 829 |  |  | $ | 672 |  |  | $ | 2,203 |  |  | $ | 1,899 |
Natural gas | 117 |  |  | 121 |  |  | 686 |  |  | 660 |
Total operating revenues | 946 |  |  | 793 |  |  | 2,889 |  |  | 2,559 |
Operating Expenses: |  |  |  |  |  |  |
Purchased power | 284 |  |  | 169 |  |  | 642 |  |  | 474 |
Natural gas purchased for resale | 19 |  |  | 26 |  |  | 188 |  |  | 173 |
Other operations and maintenance | 241 |  |  | 229 |  |  | 702 |  |  | 663 |
Depreciation and amortization | 162 |  |  | 155 |  |  | 484 |  |  | 462 |
Taxes other than income taxes | 38 |  |  | 37 |  |  | 126 |  |  | 116 |
Total operating expenses | 744 |  |  | 616 |  |  | 2,142 |  |  | 1,888 |
Operating Income | 202 |  |  | 177 |  |  | 747 |  |  | 671 |
Other Income, Net | 30 |  |  | 37 |  |  | 101 |  |  | 105 |
Interest Charges | 67 |  |  | 63 |  |  | 192 |  |  | 178 |
Income Before Income Taxes | 165 |  |  | 151 |  |  | 656 |  |  | 598 |
Income Taxes | 17 |  |  | 37 |  |  | 134 |  |  | 144 |
Net Income | 148 |  |  | 114 |  |  | 522 |  |  | 454 |
Preferred Stock Dividends | — |  |  | — |  |  | 1 |  |  | 1 |
Net Income Available to Common Shareholder | $ | 148 |  |  | $ | 114 |  |  | $ | 521 |  |  | $ | 453 |

The accompanying notes as they relate to Ameren Illinois are an integral part of these financial statements.
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AMEREN ILLINOIS COMPANY (d/b/a AMEREN ILLINOIS)
BALANCE SHEET
(Unaudited) (In millions)

| September 30, 2025 |  | December 31, 2024
ASSETS |  |  |
Current Assets: |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |
Advances to money pool | 51 |  |  | — |
Accounts receivable – trade (less allowance for doubtful accounts of $23 and $18, respectively) | 419 |  |  | 300 |
Accounts receivable – affiliates | 21 |  |  | 15 |
Unbilled revenue | 146 |  |  | 175 |
Miscellaneous accounts receivable | 36 |  |  | 28 |
Inventories | 289 |  |  | 244 |
Prepaid assets | 65 |  |  | 59 |
Current regulatory assets | 106 |  |  | 281 |
Other current assets | 8 |  |  | 8 |
Total current assets | 1,141 |  |  | 1,110 |
Property, Plant, and Equipment, Net | 16,274 |  |  | 15,530 |
Investments and Other Assets: |  |  |
Goodwill | 411 |  |  | 411 |
Regulatory assets | 1,124 |  |  | 1,011 |
Pension and other postretirement benefits | 492 |  |  | 471 |
Other assets | 756 |  |  | 697 |
Total investments and other assets | 2,783 |  |  | 2,590 |
TOTAL ASSETS | $ | 20,198 |  |  | $ | 19,230 |
LIABILITIES AND SHAREHOLDERS’ EQUITY |  |  |
Current Liabilities: |  |  |
Current maturities of long-term debt | $ | — |  |  | $ | 300 |
Short-term debt | — |  |  | 88 |
Borrowings from money pool | — |  |  | 37 |
Accounts and wages payable | 314 |  |  | 324 |
Accounts payable – affiliates | 106 |  |  | 74 |
Interest accrued | 59 |  |  | 59 |
Customer deposits | 212 |  |  | 185 |
Purchase of receivables liabilities | 55 |  |  | 43 |
Current regulatory liabilities | 101 |  |  | 79 |
Other current liabilities | 128 |  |  | 129 |
Total current liabilities | 975 |  |  | 1,318 |
Long-term Debt, Net | 6,253 |  |  | 5,549 |
Long-term Debt, Net – Related Parties | 5 |  |  | 3 |
Deferred Credits and Other Liabilities: |  |  |
Accumulated deferred income taxes and tax credits, net | 2,245 |  |  | 2,143 |
Regulatory liabilities | 2,705 |  |  | 2,573 |
Other deferred credits and liabilities | 308 |  |  | 273 |
Total deferred credits and other liabilities | 5,258 |  |  | 4,989 |
Commitments and Contingencies (Notes 2, 8, and 9) |  |  |
Shareholders’ Equity: |  |  |
Common stock, no par value, 45.0 shares authorized – 25.5 shares outstanding | — |  |  | — |
Other paid-in capital | 3,056 |  |  | 3,056 |
Preferred stock | 49 |  |  | 49 |
Retained earnings | 4,602 |  |  | 4,266 |
Total shareholders’ equity | 7,707 |  |  | 7,371 |
TOTAL LIABILITIES AND SHAREHOLDERS’ EQUITY | $ | 20,198 |  |  | $ | 19,230 |

The accompanying notes as they relate to Ameren Illinois are an integral part of these financial statements.
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AMEREN ILLINOIS COMPANY (d/b/a AMEREN ILLINOIS)
STATEMENT OF CASH FLOWS
(Unaudited) (In millions)

| Nine Months Ended September 30,
| 2025 |  | 2024
Cash Flows From Operating Activities: |  |  |
Net income | $ | 522 |  |  | $ | 454 |
Adjustments to reconcile net income to net cash provided by operating activities: |  |  |
Depreciation and amortization | 484 |  |  | 461 |
Amortization of debt issuance costs and premium/discounts | 3 |  |  | 3 |
Deferred income taxes and tax credits, net | 30 |  |  | 72 |
Allowance for equity funds used during construction | (21) |  |  | (10) |
Other | 24 |  |  | 32 |
Changes in assets and liabilities: |  |  |
Receivables | (129) |  |  | (23) |
Inventories | (45) |  |  | (35) |
Accounts and wages payable | (1) |  |  | (8) |
Taxes accrued | 26 |  |  | 118 |
Regulatory assets and liabilities | 255 |  |  | 96 |
Assets, other | (49) |  |  | (32) |
Liabilities, other | 68 |  |  | 5 |
Pension and other postretirement benefits | (50) |  |  | (66) |
Net cash provided by operating activities | 1,117 |  |  | 1,067 |
Cash Flows From Investing Activities: |  |  |
Capital expenditures | (1,127) |  |  | (1,091) |
Money pool advances, net | (51) |  |  | — |
Other | (3) |  |  | 1 |
Net cash used in investing activities | (1,181) |  |  | (1,090) |
Cash Flows From Financing Activities: |  |  |
Dividends on common stock | (185) |  |  | (50) |
Dividends on preferred stock | (1) |  |  | (1) |
Short-term debt, net | (88) |  |  | (349) |
Money pool borrowings, net | (37) |  |  | (135) |
Maturities of long-term debt | (300) |  |  | — |
Issuances of long-term debt | 711 |  |  | 624 |
Debt issuance costs | (8) |  |  | (7) |
Net cash provided by financing activities | 92 |  |  | 82 |
Net change in cash, cash equivalents, and restricted cash | 28 |  |  | 59 |
Cash, cash equivalents, and restricted cash at beginning of year | 302 |  |  | 234 |
Cash, cash equivalents, and restricted cash at end of period | $ | 330 |  |  | $ | 293 |

The accompanying notes as they relate to Ameren Illinois are an integral part of these financial statements.
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AMEREN ILLINOIS COMPANY (d/b/a AMEREN ILLINOIS)
STATEMENT OF SHAREHOLDERS’ EQUITY
(Unaudited) (In millions)

| Three Months Ended September 30, |  | Nine Months Ended September 30,
| 2025 |  | 2024 |  | 2025 |  | 2024
Common Stock | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
Other Paid-in Capital | 3,056 |  |  | 3,020 |  |  | 3,056 |  |  | 3,020 |
Preferred Stock | 49 |  |  | 49 |  |  | 49 |  |  | 49 |
Retained Earnings: |  |  |  |  |  |  |
Beginning of period | 4,564 |  |  | 4,070 |  |  | 4,266 |  |  | 3,756 |
Net income | 148 |  |  | 114 |  |  | 522 |  |  | 454 |
Dividends on common stock | (110) |  |  | (25) |  |  | (185) |  |  | (50) |
Dividends on preferred stock | — |  |  | — |  |  | (1) |  |  | (1) |
Retained earnings, end of period | 4,602 |  |  | 4,159 |  |  | 4,602 |  |  | 4,159 |
Total Shareholders’ Equity | $ | 7,707 |  |  | $ | 7,228 |  |  | $ | 7,707 |  |  | $ | 7,228 |

The accompanying notes as they relate to Ameren Illinois are an integral part of these financial statements.
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AMEREN CORPORATION (Consolidated)
UNION ELECTRIC COMPANY (Consolidated) (d/b/a Ameren Missouri)
AMEREN ILLINOIS COMPANY (d/b/a Ameren Illinois)
COMBINED NOTES TO FINANCIAL STATEMENTS
(Unaudited)
September 30, 2025
NOTE 1 – SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
General
Ameren, headquartered in St. Louis, Missouri, is a public utility holding company whose primary assets are its equity interests in its subsidiaries. Ameren’s subsidiaries are separate, independent legal entities with separate businesses, assets, and liabilities. Dividends on Ameren’s common stock and the payment of expenses by Ameren depend on distributions made to it by its subsidiaries. Ameren’s principal subsidiaries are listed below. Ameren also has other subsidiaries that conduct other activities, such as providing shared services.
•Union Electric Company, doing business as Ameren Missouri, operates a rate-regulated electric generation, transmission, and distribution business and a rate-regulated natural gas distribution business in Missouri.
•Ameren Illinois Company, doing business as Ameren Illinois, operates rate-regulated electric transmission, electric distribution, and natural gas distribution businesses in Illinois.
•ATXI operates a FERC rate-regulated electric transmission business within the MISO.
Ameren’s and Ameren Missouri’s financial statements are prepared on a consolidated basis and therefore include the accounts of their majority-owned subsidiaries. All intercompany transactions have been eliminated. Ameren Illinois has no subsidiaries. All tabular dollar amounts are in millions, unless otherwise indicated.
Our accounting policies conform to GAAP. Our financial statements reflect all adjustments (which include normal, recurring adjustments) that are necessary, in our opinion, for a fair statement of our results. The preparation of financial statements in conformity with GAAP requires management to make certain estimates and assumptions. Such estimates and assumptions affect reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the dates of financial statements, and the reported amounts of revenues and expenses during the reported periods. Actual results could differ from those estimates. The results of operations for an interim period may not give a true indication of results that may be expected for a full year. These financial statements contained in this Form 10-Q should be read in conjunction with the financial statements and accompanying notes included in the Form 10-K.
Variable Interest Entities
Variable Interest Entities that are Consolidated
AMF was formed in 2024, for the purpose of issuing and servicing securitized utility tariff bonds related to costs for the accelerated retirement of the Rush Island Energy Center. Ameren Missouri is the primary beneficiary of this entity because it has the power to direct the activities that most significantly impact the economic performance of the company, as well as the obligation to absorb losses or the right to receive benefits from the company. The entity is considered a variable interest entity primarily because its equity capitalization is insufficient to support its operations. The entity’s primary assets and liabilities are comprised of regulatory assets related to the unrecovered net plant balance associated with the facility, among other costs, and long-term debt. Ameren and Ameren Missouri consolidate AMF, which Ameren Missouri wholly owns, and both manages and controls the entity’s operating activities. For additional information on the securitization of the Rush Island Energy Center costs, see Note 2 – Rate and Regulatory Matters under Part II, Item 8, of the Form 10-K. For additional information on the securitized tariff bond issuance, see Note 5 – Long-term Debt and Equity Financings under Part II, Item 8, of the Form 10‑K.
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The following table presents the carrying values of AMF’s assets and liabilities included on Ameren’s and Ameren Missouri’s consolidated balance sheets as of September 30, 2025 and December 31, 2024:

|  | 2025 |  | 2024
Unbilled revenue(a) |  | $ | 4 |  |  | $ | — |
Other current assets(a)(b) |  | 46 |  |  | 2 |
Noncurrent regulatory assets(a) |  | 449 |  |  | 465 |
Current maturities of long-term debt(c) |  | 29 |  |  | 17 |
Interest accrued(c) |  | 18 |  |  | 1 |
Current regulatory liabilities(d) |  | 15 |  |  | — |
Long-term debt, net(c) |  | 437 |  |  | 448 |

(a)Assets may be used only to meet AMF’s obligations and commitments.
(b)Included in “Restricted cash” on Ameren Missouri’s balance sheet.
(c)The securitized tariff bondholders have no recourse to Ameren Missouri.
(d)Included in “Other current liabilities” on Ameren Missouri’s balance sheet.
Variable Interest Entities that are Not Consolidated
As of September 30, 2025, and December 31, 2024, Ameren had unconsolidated variable interests in various equity method investments, primarily to advance innovative energy technologies, totaling $60 million and $74 million, respectively, included in “Other assets” on Ameren’s consolidated balance sheet. Any earnings or losses related to these investments are included in “Other Income, Net” on Ameren’s consolidated statement of income and comprehensive income. Ameren is not the primary beneficiary of these investments because it does not have the power to direct matters that most significantly affect the activities of these variable interest entities. As of September 30, 2025, Ameren’s maximum exposure to loss related to these variable interest entities is limited to the investment in these partnerships of $60 million plus associated outstanding funding commitments of $31 million.
COLI
Ameren (parent) and Ameren Illinois have COLI, which is recorded at the net cash surrender value. The net cash surrender value is the amount that can be realized under the insurance policies at the balance sheet date. As of September 30, 2025, the cash surrender value of COLI at Ameren and Ameren Illinois was $220 million (December 31, 2024 – $260 million) and $124 million (December 31, 2024 – $118 million), respectively, while total borrowings against the policies were $117 million (December 31, 2024 – $110 million) at both Ameren and Ameren Illinois. Ameren and Ameren Illinois have the right to offset the borrowings against the cash surrender value of the policies and, consequently, present the net asset in “Other assets” on their respective balance sheets. The net cash surrender value of Ameren’s COLI is affected by the investment performance of a separate account in which Ameren holds a beneficial interest.
Accounting and Reporting Developments
Improvements to the Accounting for Internal-Use Software
In September 2025, the FASB issued authoritative guidance that made targeted improvements to the accounting for internal-use software. The guidance requires an entity to capitalize internal-use software costs when management has authorized and committed to funding the software project, and it is probable that the project will be completed and the software will be used to perform its intended function. This guidance will be effective for the Ameren Companies in the first quarter of 2028. We are currently assessing the impacts of this guidance on our results of operations, financial position, and liquidity.
NOTE 2 – RATE AND REGULATORY MATTERS
Below is a summary of updates to significant regulatory proceedings and related legal proceedings. See Note 2 – Rate and Regulatory Matters under Part II, Item 8, of the Form 10-K for additional information and a summary of our regulatory frameworks. We are unable to predict the ultimate outcome of these matters, the timing of final decisions of the various agencies and courts, or the impact on our results of operations, financial position, or liquidity.
Missouri
Missouri Senate Bill 4
In April 2025, Missouri Senate Bill 4 was enacted and 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
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resource planning, require electric utilities to submit service tariff schedules for high-demand 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.
Pursuant to the law, the PISA has been modified to include new natural gas generating units placed in service after the effective date of the law as qualifying property, plant, and equipment eligible for deferral and recovery of 85% of the related depreciation expense. These new natural gas generating units will also be included in the 85% of rate base allowed to earn a return at the applicable WACC under the PISA. The law also reduced the annual limit on increases to the electric service revenue requirement used to set customer rates, compared to the revenue requirement established in the immediately preceding rate order, due to the inclusion of incremental PISA deferrals in the revenue requirement. The annual limit in effect was 2.5% and changed to 2.25%, prorated monthly, for revenue requirements approved by the MoPSC after August 2025. Furthermore, the PISA's effective date has been extended through 2035, unless Ameren Missouri requests and receives MoPSC approval of an extension through 2040.
The law also requires an electric utility to develop and submit to the MoPSC schedules that include its service tariff applicable to customers projected to have 100 MWs or more of demand. These schedules must reasonably ensure that such high-demand customers’ rates reflect a representative share of the costs incurred to serve them and further, must prevent other lower-demand customer rates from reflecting any unjust or unreasonable costs arising from service provided to these high-demand customers.
In addition, the law made modifications to integrated resource planning, which requires Missouri electric utilities to file plans for meeting their customers' long-term energy needs. By August 2027, the MoPSC will publish a schedule for Missouri electric utilities to file integrated resource plans every four years. The MoPSC will be required to issue an order on the plans and shall determine whether the electric utility has submitted sufficient documentation and selected preferred resource plans representing a reasonable and prudent means of serving the utility's load obligations at just and reasonable rates. In making this determination, the MoPSC shall consider whether the plans appropriately balance specific factors described in the law. If the MoPSC approves the plans, requests for CCNs for new generation facilities to be constructed or acquired as a part of the approved plans shall be deemed necessary and convenient and the scope of the CCN proceedings to review projects will be limited. The approved generation facilities will also be eligible to include construction work in progress in rate base, subject to MoPSC approval, which would improve the timeliness of cash recovery. Utilities are not allowed to capitalize allowance for funds used during construction on amounts included in rate base under this provision. The amount of construction work in progress to be included in rate base is limited to prudently incurred expenditures made within the construction period for the facility.
Further, outside of the integrated resource planning process discussed above, the law allows a Missouri electric utility to request that the MoPSC authorize the inclusion of construction work in progress for new natural gas-fired generation facilities in rate base. Under this provision, utilities are not allowed to capitalize allowance for funds used during construction on projects approved to include construction work in progress in rate base. The amount of construction work in progress to be included in rate base is limited to prudently incurred expenditures made within the construction period for the facility. The provisions allowing for the inclusion of construction work in progress on natural gas-fired generation in rate base expire in December 2035, unless Ameren Missouri requests and receives MoPSC approval of an extension through 2045.
Also, beginning in July 2026 the law allows natural gas utilities to file regulatory rate reviews using a future test year, subject to MoPSC approval. If a natural gas utility is allowed to use a future test year, a reconciliation of the actual rate base and certain forecasted costs will be performed 45 days after the end of the test year. If a given year’s actual revenue requirement is less than the revenue requirement approved by the MoPSC due to changes in rate base or certain other costs, an adjustment is made to reduce natural gas operating revenues with an offset to a regulatory liability to reflect that test year’s amounts. The regulatory liability will then be refunded to customers in the next regulatory rate review and will accrue carrying costs at the applicable WACC.
April 2025 MoPSC Electric Rate Order
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 authorizes 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.
2024 Natural Gas Delivery Service Regulatory Rate Order
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 authorizes an increase of $32 million to Ameren Missouri’s annual revenue requirement for
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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.
Large Load Customer Rate Plan
In November 2025, Ameren Missouri updated its May 2025 request with the MoPSC 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. A decision by the MoPSC is expected by February 2026.
Generation and Storage Facilities
Ameren Missouri is party to agreements to acquire and/or construct various generation and storage facilities that are consistent with the 2025 Change to the 2023 PRP. The generation and storage facilities are eligible for recovery under the PISA. The following table provides information with respect to each facility:

| Agreement type | Facility size | Status of MoPSC CCN |  | In-service date(a)
Vandalia Solar Project(b) | Self-build | 50-MW | Approved March 2024 |  | Fourth quarter 2025
Bowling Green Solar Project(b) | Self-build | 50-MW | Approved March 2024 |  | First quarter 2026
Split Rail Solar Project(b) | Build-transfer(c) | 300-MW | Approved March 2024 |  | Mid-2026
Castle Bluff Natural Gas Project(d) | Self-build | 800-MW | Approved October 2024 |  | Fourth quarter 2027
Big Hollow Battery Energy Storage Project | Self-build | 400-MW | Filed June 2025(e) |  | Second quarter 2028
Big Hollow Natural Gas Project | Self-build | 800-MW | Filed June 2025(e) |  | Third quarter 2028
Reform Solar Project | Self-build | 250-MW | Filed August 2025(e) |  | Fourth quarter 2028

(a)In-service dates are dependent on the timing of regulatory approvals and construction completion, among other things.
(b)These projects collectively represent approximately $0.8 billion of capital expenditures.
(c)FERC approval of acquisition received November 2024.
(d)This project represents approximately $0.9 billion of capital expenditures.
(e)Ameren Missouri expects a decision by the MoPSC in the first half of 2026.
MISO Long-Range Transmission Projects CCN
In 2022, the MISO approved the first tranche of projects related to a preliminary long-range transmission planning roadmap of projects through 2039. A portion of these projects were assigned or awarded via a competitive bid process to various utilities, including Ameren. In 2024, ATXI filed requests for CCNs, among other things, with the MoPSC related to the MISO long-range transmission projects that it expects to construct within the MoPSC’s jurisdiction. In July 2025, the MoPSC issued an order approving a CCN for a portion of the projects and a decision on the remaining projects is expected in 2025.
Illinois
MYRP
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. Using the 2023 revenue requirement as a starting point, the approved revenue requirements in the ICC’s December 2024 order represent a cumulative four-year increase of $308 million. 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, and Ameren Illinois cannot predict the ultimate outcome of the appeals.
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2024 Electric Distribution Service Revenue Requirement Reconciliation Adjustment
In April 2025, Ameren Illinois filed for a reconciliation adjustment to its 2024 electric distribution service revenue requirement with the ICC. In September 2025, Ameren Illinois filed a revised reconciliation adjustment, requesting recovery of $60 million. The adjustment reflects Ameren Illinois’ actual 2024 recoverable costs, 2024 year-end rate base, and a capital structure composed of 50% common equity. In September 2025, the ICC staff submitted its calculation of the reconciliation adjustment, recommending recovery of $47 million. The ICC staff’s recommendation excluded an asset associated with other postretirement benefits from the rate base. An ICC decision in this proceeding is required by December 2025, and any approved adjustment would be collected from customers in 2026.
Electric Customer Energy-Efficiency Investments
In May 2025, Ameren Illinois filed its annual electric energy-efficiency formula rate update to increase its annual revenues by $12 million with the ICC. In August 2025, the ICC staff filed a recommendation supporting Ameren Illinois’ requested increase. An ICC decision in this proceeding is required by December 2025, with new rates effective in January 2026.
Electric Energy Efficiency Plan
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.
2025 Natural Gas Delivery Service Rate Review
In January 2025, Ameren Illinois filed a request with the ICC seeking approval to increase its annual revenues for natural gas delivery service. In July 2025, Ameren Illinois filed a revised request seeking to increase its annual revenues by $135 million. The request is based on a 10.7% ROE, a capital structure composed of 52% common equity, and a rate base of $3.3 billion. Ameren Illinois used a 2026 future test year in this proceeding. In August 2025, the ICC staff filed a revised recommendation to increase Ameren Illinois’ annual revenues for natural gas delivery service by $104 million. The recommendation is based on a 9.93% ROE, a capital structure composed of 50% common equity, and a rate base of $3.2 billion. In addition, in August 2025, the Illinois Attorney General's office recommended an increase to annual revenues for natural gas delivery service of $55 million, based on a 9.45% ROE, a capital structure composed of 50% common equity, and a rate base of $3.0 billion. In October 2025, the administrative law judge issued a proposed order for an increase to annual revenues of $91 million. The order was consistent with the ICC staff’s recommendation with the exception of the exclusion of the non-service cost component of the net periodic benefit income related to other postretirement benefits in the annual revenue requirement. A decision by the ICC in this proceeding is required by early December 2025, with new rates expected to be effective in early December 2025. Ameren Illinois cannot predict the level of any delivery service rate change the ICC may approve, nor whether any rate change that may eventually be approved will be sufficient to enable Ameren Illinois to recover its costs and to earn a reasonable return on investments when the rate changes go into effect.
MISO Long-Range Transmission Projects CCN
In 2022, the MISO approved the first tranche of projects related to a preliminary long-range transmission planning roadmap of projects through 2039. A portion of these projects were assigned or awarded via a competitive bidding process to various utilities, including Ameren. In July 2025, the ICC issued an order approving a request filed by Ameren Illinois and ATXI for a CCN, among other things, related to the portion of the MISO long-range transmission projects they will construct within the ICC’s jurisdiction.
Federal
MISO Transmission Rate Incentives
In 2024, the MISO approved a first set of second tranche projects related to its preliminary long-range transmission planning roadmap of projects through 2039. A portion of these projects were assigned to Ameren and are estimated to cost approximately $1.3 billion, based on the MISO’s cost estimate. In July 2025, the FERC approved transmission rate incentives relating to the second tranche projects assigned to Ameren. The incentives will allow construction work in progress to be included in rate base for projects constructed by ATXI, thereby improving the timeliness of cash recovery, and would allow recovery of prudently incurred costs, subject to FERC approval, for any portion of the projects if they are abandoned for reasons beyond the control of Ameren. ATXI will not capitalize allowance for funds used during construction on the related projects.
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FERC ROE Complaint Cases
Since November 2013, the allowed base ROE for FERC-regulated transmission rate base under the MISO tariff has been subject to customer complaint cases and has been changed by various FERC orders. In October 2024, the FERC issued an order, which decreased the allowed base ROE from 10.02% to 9.98% and required refunds, with interest, for the periods from November 2013 to February 2015 and from late September 2016 forward. In January 2025, the MISO transmission owners, including Ameren Missouri, Ameren Illinois, and ATXI, filed an appeal of the October 2024 order to the United States Court of Appeals for the District of Columbia Circuit. In March 2025, the FERC issued an order rejecting all rehearing requests of the October 2024 order. In April 2025, the MISO transmission owners, including Ameren Missouri, Ameren Illinois, and ATXI, filed an appeal of the March 2025 order to the United States Court of Appeals for the District of Columbia Circuit.
As of September 30, 2025, Ameren and Ameren Illinois had recorded liabilities in "Current regulatory liabilities" on their balance sheets of $7 million and $4 million, respectively, to reflect the expected refunds, including interest, associated with the allowed base ROE set by the October 2024 order.
NOTE 3 – SHORT-TERM DEBT AND LIQUIDITY
The liquidity needs of the Ameren Companies are supported through the use of available cash, drawings under committed credit agreements, commercial paper issuances, and, in the case of Ameren Missouri and Ameren Illinois, short-term affiliate borrowings. See Note 4 – Short-term Debt and Liquidity under Part II, Item 8, of the Form 10-K for a description of our indebtedness provisions and other covenants as well as a description of money pool agreements.
Short-term Borrowings
The Missouri Credit Agreement and the Illinois Credit Agreement are available to support issuances under Ameren (parent)’s, Ameren Missouri’s, and Ameren Illinois’ commercial paper programs, respectively, subject to borrowing sublimits, and to support the issuance of letters of credit. As of September 30, 2025, based on commercial paper outstanding and letters of credit issued under the Credit Agreements, along with cash and cash equivalents, the net liquidity available to Ameren (parent), Ameren Missouri, and Ameren Illinois, collectively, was $1.6 billion. The Ameren Companies were in compliance with the covenants in their Credit Agreements as of September 30, 2025. As of September 30, 2025, the ratios of consolidated indebtedness to consolidated total capitalization, calculated in accordance with the provisions of the Credit Agreements, were 61%, 49%, and 45% for Ameren, Ameren Missouri, and Ameren Illinois, respectively.
The following table presents commercial paper outstanding, net of issuance discounts, as of September 30, 2025, and December 31, 2024. There were no borrowings outstanding under the Credit Agreements as of September 30, 2025, or December 31, 2024.

| September 30, 2025 |  |  | December 31, 2024
Ameren (parent) | $ | 644 |  |  |  | $ | 1,055 |
Ameren Missouri | 259 |  |  |  | — |
Ameren Illinois | — |  |  |  | 88 |
Ameren consolidated | $ | 903 |  |  |  | $ | 1,143 |

The following table summarizes the activity and relevant interest rates for Ameren (parent)’s, Ameren Missouri’s, and Ameren Illinois’ commercial paper issuances under the Credit Agreements for the nine months ended September 30, 2025 and 2024:

|  | Ameren (parent) |  | Ameren Missouri |  | Ameren Illinois |  | Ameren Consolidated |
2025 |  |  |  |  |  |  |  |  |
Average daily amount outstanding |  | $ | 637 |  |  | $ | 245 |  |  | $ | 130 |  |  | $ | 1,012 |  |
Weighted-average interest rate |  | 4.60 | % |  | 4.58 | % |  | 4.55 | % |  | 4.59 | % |
Peak amount outstanding during period(a) |  | $ | 1,139 |  |  | $ | 650 |  |  | $ | 425 |  |  | $ | 1,603 |  |
Peak interest rate |  | 4.75 | % |  | 4.72 | % |  | 4.70 | % |  | 4.75 | % |
2024 |  |  |  |  |  |  |  |  |
Average daily amount outstanding |  | $ | 177 |  |  | $ | 187 |  |  | $ | 256 |  |  | $ | 620 |  |
Weighted-average interest rate |  | 5.46 | % |  | 5.52 | % |  | 5.57 | % |  | 5.53 | % |
Peak amount outstanding during period(a) |  | $ | 948 |  |  | $ | 576 |  |  | $ | 694 |  |  | $ | 1,542 |  |
Peak interest rate |  | 5.60 | % |  | 5.68 | % |  | 5.68 | % |  | 5.68 | % |

(a)The timing of peak outstanding commercial paper issuances under the Credit Agreements varies by company. Therefore, the sum of individual company peak amounts may not equal the Ameren consolidated peak amount for the period.
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Money Pools
Ameren has money pool agreements with and among its subsidiaries to coordinate and provide for certain short-term cash and working capital requirements. The average interest rate for borrowings under the utility money pool for the three and nine months ended September 30, 2025, was 4.53% and 4.56%, respectively (2024 – 5.29% and 5.37%). See Note 8 – Related-party Transactions for the amount of interest income and expense from the utility money pool agreements recorded by Ameren Missouri and Ameren Illinois for the three and nine months ended September 30, 2025 and 2024.
NOTE 4 – LONG-TERM DEBT AND EQUITY FINANCINGS
Ameren
For the three and nine months ended September 30, 2025, Ameren issued a total of 0.1 million and 0.3 million shares of common stock, under its DRPlus and 401(k) plan, and received proceeds of $3 million and $28 million. As of September 30, 2025, Ameren had a receivable of $7 million related to issuances of common stock under its DRPlus and 401(k) plan. In addition, in the first quarter of 2025, Ameren issued 0.3 million shares of common stock valued at $25 million upon the settlement of stock-based compensation awards.
Ameren has entered into an equity distribution sales agreement pursuant to which Ameren may offer and sell from time to time its common stock through an ATM program, which includes the ability to enter into forward sale agreements. In August 2025, Ameren increased the amount of common stock available for sale under the ATM program by $1.25 billion to a total of $3 billion. There were no shares issued under the ATM program during the three and nine months ended September 30, 2025. As of September 30, 2025, Ameren had approximately $1.5 billion of common stock remaining available for sale under the ATM program.
Forward sale agreements outstanding as of September 30, 2025 under the ATM program for 5.8 million shares, can be settled at Ameren’s discretion on or prior to dates ranging from January 23, 2026, to March 6, 2026. The initial forward sale price for the agreements ranged from $81.00 to $98.66, with an average initial forward sale price of $91.02. Additionally in May 2025, Ameren entered into forward sale agreements separate from the ATM program with multiple counterparties relating to 6.4 million shares of common stock. The forward sale agreements can be settled at Ameren’s discretion on or prior to January 15, 2027, and the initial forward sale price under these agreements was $91.89 per share. On a settlement date or dates, if Ameren elects to physically settle a forward sale agreement, Ameren will issue shares of common stock to the counterparties at the then-applicable forward sale price. Each initial forward sale price is subject to adjustment based on a floating interest rate factor equal to the overnight bank funding rate less a spread of 75 basis points, and will be subject to decrease on certain dates specified in the forward sale agreements by specified amounts related to expected dividends on shares of the common stock during the term of the forward sale agreements. If the overnight bank funding rate is less than or more than the spread on any day, the interest rate factor will result in a reduction or an increase, respectively, of the forward sale price. The forward sale agreements will be physically settled unless Ameren elects to settle in cash or to net share settle.
At September 30, 2025, Ameren could have settled the forward sale agreements with physical delivery of 12.2 million shares of common stock to the respective counterparties in exchange for cash of $1.1 billion. Alternatively, the forward sale agreements could have also been net settled at September 30, 2025, with delivery of approximately $158 million of cash or approximately 1.5 million shares of common stock to the counterparties. In connection with the forward sale agreements outstanding at September 30, 2025, the various counterparties, or their affiliates, borrowed from third parties and sold 12.2 million shares of common stock. The gross sales price of these shares totaled $1.1 billion. Ameren does not receive any proceeds from such sales of borrowed shares. The forward sale agreements have been classified as equity transactions.
In March 2025, Ameren (parent) issued $750 million of 5.375% senior unsecured notes due March 2035, with interest payable semiannually on March 15 and September 15 of each year, beginning September 15, 2025. Net proceeds from this issuance were used for general corporate purposes, including the repayment of short-term debt.
In June 2025, Ameren (parent) purchased senior secured notes and first mortgage bonds issued by Ameren Missouri and first mortgage bonds issued by Ameren Illinois for $24 million in the aggregate. On a consolidated basis, Ameren (parent)’s repurchase of these senior secured notes and first mortgage bonds were accounted for as a debt extinguishment and resulted in a pre-tax gain of $8 million, which is reflected in “Other Income, Net” on Ameren’s consolidated statement of income. Interest expense related to repurchased bonds was $1 million and $2 million for the three and nine months ended September 30, 2025.
Ameren Missouri
In April 2025, Ameren Missouri issued $500 million of 5.25% first mortgage bonds due April 2035, with interest payable semiannually on April 15 and October 15 of each year, beginning October 15, 2025. Net proceeds from this issuance were used to repay short-term debt.
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Ameren Illinois
In March and September 2025, Ameren Illinois issued $350 million and $350 million, respectively, of 5.625% first mortgage bonds due March 2055, with interest payable semiannually on March 1 and September 1 of each year, beginning September 1, 2025 and March 1, 2026, respectively. Net proceeds from the March 2025 issuance were used to repay $300 million principal amount of its 3.25% senior secured notes that matured in March 2025, and net proceeds of both issuances were used to repay a portion of its short-term debt.
Indenture Provisions and Other Covenants
See Note 5 – Long-term Debt and Equity Financings under Part II, Item 8, of the Form 10-K for a description of our indenture provisions and other covenants, as well as restrictions on the payment of dividends. At September 30, 2025, the Ameren Companies were in compliance with the provisions and covenants contained in their indentures and articles of incorporation, as applicable, and ATXI was in compliance with the provisions and covenants contained in its note purchase agreements.
Off-balance-sheet Arrangements
At September 30, 2025, none of the Ameren Companies had any material off-balance-sheet financing arrangements, other than their investment in unconsolidated variable interest entities, letters of credit, and the multiple forward sale agreements relating to common stock. See Note 1 – Summary of Significant Accounting Policies for further detail concerning variable interest entities.
NOTE 5 – OTHER INCOME, NET
The following table presents the components of “Other Income, Net” in the Ameren Companies’ statements of income for the three and nine months ended September 30, 2025 and 2024:

| Three Months |  | Nine Months |
| 2025 |  | 2024 |  | 2025 |  | 2024 |
Ameren: |  |  |  |  |  |  |  |
Allowance for equity funds used during construction | $ | 21 |  |  | $ | 23 |  |  | $ | 60 |  |  | $ | 48 |  |
Other interest income | 10 |  |  | 8 |  |  | 31 |  |  | 29 |  |
Non-service cost components of net periodic benefit income(a) | 59 |  |  | 76 |  |  | 187 |  |  | 228 |  |
Miscellaneous income | 6 |  |  | — |  |  | 13 |  |  | 6 |  |
Gain on the extinguishment of debt(b) | — |  |  | — |  |  | 8 |  |  | — |  |
Losses related to equity method investments | (9) |  |  | (2) |  |  | (19) |  |  | (1) |  |
Donations | (6) |  |  | (1) |  |  | (9) |  |  | (5) |  |
Miscellaneous expense | (5) |  |  | (3) |  |  | (14) |  |  | (12) |  |
Total Other Income, Net | $ | 76 |  |  | $ | 101 |  |  | $ | 257 |  |  | $ | 293 |  |
Ameren Missouri: |  |  |  |  |  |  |  |
Allowance for equity funds used during construction | $ | 14 |  |  | $ | 15 |  |  | $ | 37 |  |  | $ | 38 |  |
Other interest income | 3 |  |  | 2 |  |  | 7 |  |  | 7 |  |
Non-service cost components of net periodic benefit income(a) | 29 |  |  | 35 |  |  | 96 |  |  | 104 |  |
Miscellaneous income | 4 |  |  | 1 |  |  | 6 |  |  | 3 |  |
Donations | (2) |  |  | — |  |  | (4) |  |  | (2) |  |
Miscellaneous expense | (3) |  |  | (2) |  |  | (7) |  |  | (6) |  |
Total Other Income, Net | $ | 45 |  |  | $ | 51 |  |  | $ | 135 |  |  | $ | 144 |  |
Ameren Illinois: |  |  |  |  |  |  |  |
Allowance for equity funds used during construction | $ | 6 |  |  | $ | 8 |  |  | $ | 21 |  |  | $ | 10 |  |
Other interest income | 7 |  |  | 7 |  |  | 24 |  |  | 22 |  |
Non-service cost components of net periodic benefit income | 21 |  |  | 25 |  |  | 61 |  |  | 78 |  |
Miscellaneous income | 2 |  |  | — |  |  | 7 |  |  | 3 |  |
Donations | (4) |  |  | — |  |  | (5) |  |  | (2) |  |
Miscellaneous expense | (2) |  |  | (3) |  |  | (7) |  |  | (6) |  |
Total Other Income, Net | $ | 30 |  |  | $ | 37 |  |  | $ | 101 |  |  | $ | 105 |  |

(a)For the three and nine months ended September 30, 2025, the non-service cost components of net periodic benefit income were adjusted by amounts deferred of $(9) million and $(41) million, respectively, due to a regulatory tracking mechanism for the difference between the level of such costs incurred by Ameren Missouri under GAAP and the level of such costs included in rates. The deferral was $(11) million and $(31) million, respectively, for the three and nine months ended September 30, 2024. See Note 11 – Retirement Benefits for additional information.
(b)See Note 4 – Long-term Debt and Equity Financings for additional information on Ameren (parent)’s repurchase of Ameren Missouri’s senior secured notes and first mortgage bonds and Ameren Illinois’ first mortgage bonds that were accounted for as a debt extinguishment.
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NOTE 6 – DERIVATIVE FINANCIAL INSTRUMENTS
We use derivatives to manage the risk of changes in market prices for natural gas, power, and interest rates, as well as the risk of changes in rail transportation surcharges through fuel oil hedges. Such price fluctuations may cause the following:
•an unrealized appreciation or depreciation of our contracted commitments to purchase or sell when purchase or sale prices under the commitments are compared with current commodity prices;
•market values of natural gas inventories that differ from the cost of this commodity in inventory;
•actual cash outlays for interest expense and the purchase of commodities that differ from anticipated cash outlays; and
•actual off-system sales revenues that differ from anticipated revenues.
The derivatives that we use to hedge these risks are governed by our risk management policies for forward contracts, futures, options, and swaps. Our net positions are continually assessed within our structured hedging programs to determine whether new or offsetting transactions are required. The goal of the hedging ‘program is generally to mitigate financial risks while ensuring that sufficient volumes are available to meet our requirements. Contracts we enter into as part of our risk management program may be settled financially, settled by physical delivery, or net settled with the counterparty.
All contracts considered to be derivative instruments are required to be recorded on the balance sheet at their fair values, unless the NPNS exception applies. Many of our physical contracts, such as our purchased power contracts, qualify for the NPNS exception to derivative accounting rules. The revenue or expense on NPNS contracts is recognized at the contract price upon physical delivery. The following disclosures exclude NPNS contracts and other non-derivative commodity contracts that are accounted for under the accrual method of accounting.
If we determine that a contract meets the definition of a derivative and is not eligible for the NPNS exception, we review the contract to determine whether the resulting gains or losses qualify for regulatory deferral. Derivative contracts that qualify for regulatory deferral are recorded at fair value, with changes in fair value recorded as regulatory assets or liabilities in the period in which the change occurs. We believe derivative losses and gains deferred as regulatory assets and liabilities are probable of recovery, or refund, through future rates charged to customers. Regulatory assets and liabilities are amortized to operating income as related losses and gains are reflected in rates charged to customers. Therefore, gains and losses on these derivatives have no effect on operating income. As of September 30, 2025, and December 31, 2024, all commodity contracts that met the definition of a derivative and were not eligible for the NPNS exception received regulatory deferral. Interest rate hedges entered into by Ameren (parent) and discussed below do not receive regulatory deferral and were included in accumulated OCI as Ameren (parent) is not a rate-regulated entity. The cash flows from our derivative financial instruments follow the cash flow classification of the hedged item.
Ameren (parent) entered into interest rate swaps to hedge a portion of its interest rate risk on cash flows related to certain forecasted debt issuances to occur in 2026 and 2027. The interest rate swaps are designated as cash flow hedges and the corresponding changes in fair value each period are initially recorded on the balance sheet in “Accumulated other comprehensive loss” and reclassified into earnings when the debt is issued and the corresponding interest payments affect earnings during the debt term. As of September 30, 2025, and December 31, 2024, Ameren had interest rate swaps with notional amounts of $660 million and $140 million, respectively. Ameren recorded an unrealized loss, net of income tax benefits, on the change in fair value of interest rate swaps of less than $1 million and $6 million to "Accumulated other comprehensive loss" for the three and nine months ended September 30, 2025.
The following table presents open gross commodity contract volumes by commodity type for derivative assets and liabilities as of September 30, 2025, and December 31, 2024. As of September 30, 2025, these contracts extended through October 2028, October 2031 and May 2032 for fuel oils, natural gas, and power, respectively.

| Quantity (in millions, except as indicated)
| September 30, 2025 | December 31, 2024
Commodity | Ameren Missouri | Ameren Illinois | Ameren | Ameren Missouri | Ameren Illinois | Ameren
Fuel oils (in gallons) | 23 |  | — |  | 23 |  | 23 |  | — |  | 23 |
Natural gas (in MMBtu) | 50 |  | 211 |  | 261 |  | 45 |  | 213 |  | 258 |
Power (in MWhs) | — |  | 4 |  | 4 |  | — |  | 4 |  | 4 |

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The following table presents the carrying value and balance sheet location of all derivative commodity contracts, none of which were designated as hedging instruments because all qualify for regulatory deferral, as of September 30, 2025, and December 31, 2024:

|  |  | September 30, 2025 | December 31, 2024
| Balance Sheet Location |  | Ameren Missouri |  |  | Ameren Illinois |  |  | Ameren |  |  |  | Ameren Missouri |  |  | Ameren Illinois |  |  | Ameren
Natural gas | Other current assets |  | $ | 1 |  |  |  | $ | 3 |  |  |  | $ | 4 |  |  |  |  | $ | 2 |  |  |  | $ | 2 |  |  |  | $ | 4 |
| Other assets |  | 1 |  |  |  | 5 |  |  |  | 6 |  |  |  |  | 2 |  |  |  | 4 |  |  |  | 6 |
Power | Other current assets |  | 22 |  |  |  | — |  |  |  | 22 |  |  |  |  | 6 |  |  |  | — |  |  |  | 6 |
| Total assets |  | $ | 24 |  |  |  | $ | 8 |  |  |  | $ | 32 |  |  |  |  | $ | 10 |  |  |  | $ | 6 |  |  |  | $ | 16 |
Fuel oils | Other current liabilities |  | $ | 2 |  |  |  | $ | — |  |  |  | $ | 2 |  |  |  |  | $ | 2 |  |  |  | $ | — |  |  |  | $ | 2 |
| Other deferred credits and liabilities |  | 1 |  |  |  | — |  |  |  | 1 |  |  |  |  | 2 |  |  |  | — |  |  |  | 2 |
Natural gas | Other current liabilities |  | 3 |  |  |  | 18 |  |  |  | 21 |  |  |  |  | 5 |  |  |  | 22 |  |  |  | 27 |
| Other deferred credits and liabilities |  | 5 |  |  |  | 8 |  |  |  | 13 |  |  |  |  | 6 |  |  |  | 13 |  |  |  | 19 |
Power | Other current liabilities |  | 1 |  |  |  | 10 |  |  |  | 11 |  |  |  |  | — |  |  |  | 10 |  |  |  | 10 |
| Other deferred credits and liabilities |  | — |  |  |  | 52 |  |  |  | 52 |  |  |  |  | — |  |  |  | 43 |  |  |  | 43 |
| Total liabilities |  | $ | 12 |  |  |  | $ | 88 |  |  |  | $ | 100 |  |  |  |  | $ | 15 |  |  |  | $ | 88 |  |  |  | $ | 103 |

The Ameren Companies elect to present the fair value amounts of derivative assets and derivative liabilities subject to an enforceable master netting arrangement or similar agreement at the gross amounts on the balance sheet. However, if the gross amounts recognized on the balance sheet were netted with derivative instruments and cash collateral received or posted, the net amounts would not be materially different from the gross amounts at September 30, 2025, and December 31, 2024.
Credit Risk
In determining our concentrations of credit risk related to derivative instruments, we review our individual counterparties and categorize each counterparty into groupings according to the primary business in which each engages. As of September 30, 2025, if counterparty groups were to fail completely to perform on contracts, the Ameren Companies’ maximum exposure related to derivative assets would have been immaterial with or without consideration of the application of master netting arrangements or similar agreements and collateral held.
Certain of our derivative instruments contain collateral provisions tied to the Ameren Companies’ credit ratings. If our credit ratings were downgraded below investment grade, or if a counterparty with reasonable grounds for uncertainty regarding our ability to satisfy an obligation requested adequate assurance of performance, additional collateral postings might be required. The additional collateral required is the net liability position allowed under master netting arrangements or similar agreements, assuming (1) the credit risk-related contingent features underlying these arrangements were triggered and (2) those counterparties with rights to do so requested collateral. As of September 30, 2025, the aggregate fair value of derivative instruments with credit risk-related contingent features in a gross liability position, the cash collateral posted, and the aggregate amount of additional collateral that counterparties could require were each immaterial to Ameren, Ameren Missouri, and Ameren Illinois.
NOTE 7 – FAIR VALUE MEASUREMENTS
Fair value is defined as the price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Fair value measurements are classified in three levels based on the fair value hierarchy as defined by GAAP. See Note 8 – Fair Value Measurements under Part II, Item 8, of the Form 10-K for information related to hierarchy levels and valuation techniques.
We consider nonperformance risk in our valuation of derivative instruments by analyzing our own credit standing and the credit standing of our counterparties, and by considering any credit enhancements (e.g., collateral). Included in our valuation, and based on current market conditions, is a valuation adjustment for counterparty default derived from market data such as the price of credit default swaps, bond yields, and credit ratings. No material gains or losses related to valuation adjustments for counterparty default risk were recorded at Ameren, Ameren Missouri, or Ameren Illinois in the three and nine months ended September 30, 2025 or 2024. At September 30, 2025, and December 31, 2024, the counterparty default risk valuation adjustment related to derivative contracts was immaterial for Ameren, Ameren Missouri, and Ameren Illinois.
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The following table sets forth, by level within the fair value hierarchy, our assets and liabilities measured at fair value on a recurring basis as of September 30, 2025, and December 31, 2024:

|  | September 30, 2025 |  |  | December 31, 2024 |
|  | Level 1 | Level 2 | Level 3 | Total |  |  | Level 1 | Level 2 | Level 3 | Total |
Assets: |  |  |  |  |  |  |  |  |  |  |
Ameren Missouri |  |  |  |  |  |  |  |  |  |  |
| Derivative assets – commodity contracts: |  |  |  |  |  |  |  |  |  |  |
| Natural gas | $ | — |  | $ | 2 |  | $ | — |  | $ | 2 |  |  |  | $ | — |  | $ | 4 |  | $ | — |  | $ | 4 |  |
| Power | — |  | — |  | 22 |  | 22 |  |  |  | — |  | — |  | 6 |  | 6 |  |
| Total derivative assets – commodity contracts | $ | — |  | $ | 2 |  | $ | 22 |  | $ | 24 |  |  |  | $ | — |  | $ | 4 |  | $ | 6 |  | $ | 10 |  |
| Nuclear decommissioning trust fund: |  |  |  |  |  |  |  |  |  |  |
| Equity securities: |  |  |  |  |  |  |  |  |  |  |
| U.S. large capitalization | $ | 1,001 |  | $ | — |  | $ | — |  | $ | 1,001 |  |  |  | $ | 911 |  | $ | — |  | $ | — |  | $ | 911 |  |
| Debt securities: |  |  |  |  |  |  |  |  |  |  |
| U.S. Treasury and agency securities | — |  | 235 |  | — |  | 235 |  |  |  | — |  | 191 |  | — |  | 191 |  |
| Corporate bonds | — |  | 174 |  | — |  | 174 |  |  |  | — |  | 145 |  | — |  | 145 |  |
| Other | — |  | 84 |  | — |  | 84 |  |  |  | — |  | 86 |  | — |  | 86 |  |
| Total nuclear decommissioning trust fund | $ | 1,001 |  | $ | 493 |  | $ | — |  | $ | 1,494 |  | (a) |  | $ | 911 |  | $ | 422 |  | $ | — |  | $ | 1,333 |  | (a)
| Total Ameren Missouri | $ | 1,001 |  | $ | 495 |  | $ | 22 |  | $ | 1,518 |  |  |  | $ | 911 |  | $ | 426 |  | $ | 6 |  | $ | 1,343 |  |
Ameren Illinois |  |  |  |  |  |  |  |  |  |  |
| Derivative assets – commodity contracts: |  |  |  |  |  |  |  |  |  |  |
| Natural gas | $ | — |  | $ | 4 |  | $ | 4 |  | $ | 8 |  |  |  | $ | — |  | $ | 3 |  | $ | 3 |  | $ | 6 |  |
| Total Ameren Illinois | $ | — |  | $ | 4 |  | $ | 4 |  | $ | 8 |  |  |  | $ | — |  | $ | 3 |  | $ | 3 |  | $ | 6 |  |
Ameren |  |  |  |  |  |  |  |  |  |  |
| Derivative assets – commodity contracts(b) | $ | — |  | $ | 6 |  | $ | 26 |  | $ | 32 |  |  |  | $ | — |  | $ | 7 |  | $ | 9 |  | $ | 16 |  |
| Nuclear decommissioning trust fund(c) | 1,001 |  | 493 |  | — |  | 1,494 |  | (a) |  | 911 |  | 422 |  | — |  | 1,333 |  | (a)
| Total Ameren | $ | 1,001 |  | $ | 499 |  | $ | 26 |  | $ | 1,526 |  |  |  | $ | 911 |  | $ | 429 |  | $ | 9 |  | $ | 1,349 |  |
Liabilities: |  |  |  |  |  |  |  |  |  |  |
Ameren Missouri |  |  |  |  |  |  |  |  |  |  |
| Derivative liabilities – commodity contracts: |  |  |  |  |  |  |  |  |  |  |
| Fuel oils | $ | 3 |  | $ | — |  | $ | — |  | $ | 3 |  |  |  | $ | 4 |  | $ | — |  | $ | — |  | $ | 4 |  |
| Natural gas | — |  | 8 |  | — |  | 8 |  |  |  | — |  | 11 |  | — |  | 11 |  |
| Power | — |  | — |  | 1 |  | 1 |  |  |  | — |  | — |  | — |  | — |  |
| Total Ameren Missouri | $ | 3 |  | $ | 8 |  | $ | 1 |  | $ | 12 |  |  |  | $ | 4 |  | $ | 11 |  | $ | — |  | $ | 15 |  |
Ameren Illinois |  |  |  |  |  |  |  |  |  |  |
| Derivative liabilities – commodity contracts: |  |  |  |  |  |  |  |  |  |  |
| Natural gas | $ | 1 |  | $ | 22 |  | $ | 3 |  | $ | 26 |  |  |  | $ | 1 |  | $ | 28 |  | $ | 6 |  | $ | 35 |  |
| Power | — |  | — |  | 62 |  | 62 |  |  |  | — |  | — |  | 53 |  | 53 |  |
| Total Ameren Illinois | $ | 1 |  | $ | 22 |  | $ | 65 |  | $ | 88 |  |  |  | $ | 1 |  | $ | 28 |  | $ | 59 |  | $ | 88 |  |
Ameren |  |  |  |  |  |  |  |  |  |  |
| Derivative liabilities – commodity contracts(b) | $ | 4 |  | $ | 30 |  | $ | 66 |  | $ | 100 |  |  |  | $ | 5 |  | $ | 39 |  | $ | 59 |  | $ | 103 |  |

(a)Balance excludes $8 million and $9 million of cash and cash equivalents, receivables, payables, and accrued income, net, for September 30, 2025, and December 31, 2024, respectively.
(b)See the Ameren Missouri and Ameren Illinois sections of the table for a breakout of the fair value of Ameren’s derivative assets and liabilities by type of commodity.
(c)See the Ameren Missouri section of the table for a breakout of the fair value of Ameren’s nuclear decommissioning trust fund by investment type.
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Level 3 fuel oils and natural gas derivative contract assets and liabilities measured at fair value on a recurring basis were immaterial for all periods presented. The following table presents the fair value reconciliation of Level 3 power derivative contract assets and liabilities measured at fair value on a recurring basis for the three and nine months ended September 30, 2025 and 2024:

| 2025 |  |  | 2024
| Ameren Missouri | Ameren Illinois |  |  | Ameren |  |  | Ameren Missouri | Ameren Illinois | Ameren
For the three months ended September 30: |  |  |  |  |  |  |  |  |  |
Beginning balance at July 1 | $ | 13 |  | $ | (76) |  |  |  | $ | (63) |  |  |  | $ | 14 |  | $ | (61) |  | $ | (47) |
Realized and unrealized gains/(losses) included in regulatory assets/liabilities | 12 |  | 12 |  |  |  | 24 |  |  |  | (1) |  | (21) |  | (22) |
Settlements | (4) |  | 2 |  |  |  | (2) |  |  |  | (3) |  | 4 |  | 1 |
Ending balance at September 30 | $ | 21 |  | $ | (62) |  |  |  | $ | (41) |  |  |  | $ | 10 |  | $ | (78) |  | $ | (68) |
Change in unrealized gains/(losses) related to assets/liabilities held at September 30 | $ | 11 |  | $ | 11 |  |  |  | $ | 22 |  |  |  | $ | (1) |  | $ | (19) |  | $ | (20) |
For the nine months ended September 30: |  |  |  |  |  |  |  |  |  |
Beginning balance at January 1 | $ | 6 |  | $ | (53) |  |  |  | $ | (47) |  |  |  | $ | 4 |  | $ | (68) |  | $ | (64) |
Realized and unrealized gains/(losses) included in regulatory assets/liabilities | 28 |  | (18) |  |  |  | 10 |  |  |  | 13 |  | (23) |  | (10) |
Settlements | (13) |  | 9 |  |  |  | (4) |  |  |  | (7) |  | 13 |  | 6 |
Ending balance at September 30 | $ | 21 |  | $ | (62) |  |  |  | $ | (41) |  |  |  | $ | 10 |  | $ | (78) |  | $ | (68) |
Change in unrealized gains/(losses) related to assets/liabilities held at September 30 | $ | 21 |  | $ | (17) |  |  |  | $ | 4 |  |  |  | $ | 10 |  | $ | (18) |  | $ | (8) |

All gains or losses related to our Level 3 derivative commodity contracts are expected to be collected or refunded through customer rates; therefore, there is no impact to either net income or other comprehensive income resulting from changes in the fair value of these instruments.
The following table describes the valuation techniques and significant unobservable inputs utilized for the fair value of our Level 3 power derivative contract assets and liabilities as of September 30, 2025, and December 31, 2024:

|  |  | Fair Value |  |  |  | Weighted Average(b) |
| Commodity |  | Assets |  | Liabilities | Valuation Technique(s) | Unobservable Input(a) | Range |
2025 | Power(c) | $ | 22 | $ | (63) | Discounted cash flow | Average forward peak and off-peak pricing – forwards/swaps ($/MWh) | 33 – 67 | 43 |
|  |  |  |  |  |  | Nodal basis ($/MWh) | (10) – 2 | (5) |
2024 | Power(c) | $ | 6 | $ | (53) | Discounted cash flow | Average forward peak and off-peak pricing – forwards/swaps ($/MWh) | 32 – 69 | 45 |
|  |  |  |  |  |  | Nodal basis ($/MWh) | (8) – (2) | (5) |

(a)Generally, significant increases (decreases) in these inputs in isolation would result in a significantly higher (lower) fair value measurement.
(b)Unobservable inputs were weighted by relative fair value.
(c)Valuations use visible forward prices adjusted for nodal-to-hub basis differentials.
The following table sets forth the carrying amount and, by level within the fair value hierarchy, the fair value of long-term debt (including current portion) disclosed, but not recorded, at fair value as of September 30, 2025, and December 31, 2024:

Long-Term Debt (Including Current Portion): | Carrying Amount(a) |  |  |  | Fair Value |  |
|  |  | Level 2 |  | Level 3 |  | Total
| September 30, 2025
Ameren(b) | $ | 19,201 |  |  |  |  | $ | 17,532 |  |  | $ | 556 |  | (c) | $ | 18,088 |
Ameren Missouri(d) | 8,246 |  |  |  |  | 7,662 |  |  | — |  |  | 7,662 |
Ameren Illinois(d) | 6,258 |  |  |  |  | 5,815 |  |  | — |  |  | 5,815 |
| December 31, 2024
Ameren(b) | $ | 17,579 |  |  |  |  | $ | 15,395 |  |  | $ | 538 |  | (c) | $ | 15,933 |
Ameren Missouri(d) | 7,745 |  |  |  |  | 6,926 |  |  | — |  |  | 6,926 |
Ameren Illinois(d) | 5,852 |  |  |  |  | 5,243 |  |  | — |  |  | 5,243 |

(a)Included unamortized debt issuance costs, which were excluded from the fair value measurement, of $139 million, $63 million, and $56 million for Ameren, Ameren Missouri, and Ameren Illinois, respectively, as of September 30, 2025. Included unamortized debt issuance costs, which were excluded from the fair value measurement, of $129 million, $62 million, and $51 million for Ameren, Ameren Missouri, and Ameren Illinois, respectively, as of December 31, 2024.
(b)Amount excludes Ameren (parent)’s repurchase of Ameren Missouri’s senior secured notes and first mortgage bonds and Ameren Illinois’ first mortgage bonds.
(c)The Level 3 fair value amount consists of ATXI’s senior unsecured notes.
(d)Amount includes Ameren Missouri’s senior secured notes and first mortgage bonds and Ameren Illinois’ first mortgage bonds that were repurchased by Ameren (parent).
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The Ameren Companies’ carrying amounts of cash, cash equivalents, and restricted cash approximate fair value and are considered Level 1 in the fair value hierarchy. The Ameren Companies’ short-term borrowings approximate fair value because of the short-term nature of these instruments and are considered Level 2 in the fair value hierarchy.
NOTE 8 – RELATED-PARTY TRANSACTIONS
In the ordinary course of business, Ameren Missouri and Ameren Illinois have engaged in, and may in the future engage in, affiliate transactions. These transactions primarily consist of natural gas and power purchases and sales, services received or rendered, and borrowings and lendings. Transactions between Ameren’s subsidiaries are reported as affiliate transactions on their individual financial statements, but those transactions are eliminated in consolidation for Ameren’s consolidated financial statements. For a discussion of material related-party agreements and money pool agreements, see Note 13 – Related-party Transactions and Note 4 – Short-term Debt and Liquidity under Part II, Item 8, of the Form 10-K.
Support Services Agreements
Ameren Missouri and Ameren Illinois had long-term receivables included in “Other assets” from Ameren Services of $18 million and $20 million, respectively, as of September 30, 2025, and $29 million and $32 million, respectively, as of December 31, 2024, related to Ameren Services’ allocated portion of Ameren’s pension and postretirement benefit plans.
Tax Allocation Agreement
See Note 1 – Summary of Significant Accounting Policies under Part II, Item 8, of the Form 10-K for a discussion of the tax allocation agreement. The following table presents the affiliate balances related to income taxes for Ameren Missouri and Ameren Illinois as of September 30, 2025, and December 31, 2024:

| September 30, 2025 |  |  | December 31, 2024
| Ameren Missouri | Ameren Illinois |  |  | Ameren Missouri | Ameren Illinois
Income taxes payable to parent(a) | $ | 3 | $ | 67 |  |  | $ | — | $ | 32
Income taxes receivable from parent(b) | 2 | — |  |  | 28 | —

(a)Included in “Accounts payable – affiliates” on the balance sheet.
(b)Included in “Accounts receivable – affiliates” on the balance sheet.
Effects of Related-party Transactions on the Statement of Income
The following table presents the impact on Ameren Missouri and Ameren Illinois of related-party transactions for the three and nine months ended September 30, 2025 and 2024:

|  |  |  | Three Months |  | Nine Months
Agreement | Income Statement Line Item |  |  | Ameren Missouri |  | Ameren Illinois |  | Ameren Missouri |  | Ameren Illinois
Ameren Missouri and Ameren Illinois | Operating Revenues | 2025 | $ | 8 |  | $ | (b) | $ | 23 |  | $ | 1 |
rent and facility services |  | 2024 |  | 8 |  |  | (b) |  | 23 |  |  | (b)
Ameren Missouri and Ameren Illinois miscellaneous | Operating Revenues | 2025 | $ | 1 |  | $ | (b) | $ | 1 |  | $ | 5 |
support services |  | 2024 |  | 1 |  |  | (b) |  | 2 |  |  | 1 |
Total Operating Revenues |  | 2025 | $ | 9 |  | $ | (b) | $ | 24 |  | $ | 6 |
|  | 2024 |  | 9 |  |  | (b) |  | 25 |  |  | 1 |
Ameren Missouri and Ameren Illinois | Purchased Power | 2025 | $ | 2 |  | $ | 1 |  | $ | 7 |  | $ | 2 |
transmission services from ATXI |  | 2024 |  | 3 |  |  | 1 |  |  | 7 |  |  | 2 |
Ameren Missouri and Ameren Illinois | Other Operations and Maintenance | 2025 | $ | (b) | $ | (b) | $ | (b) | $ | 3 |
rent and facility services |  | 2024 |  | (b) |  | (b) |  | (b) |  | (b)
Ameren Services support services | Other Operations and Maintenance | 2025 | $ | 42 |  | $ | 39 |  | $ | 130 |  | $ | 119 |
agreement |  | 2024 |  | 41 |  |  | 38 |  |  | 122 |  |  | 115 |
Total Other Operations and |  | 2025 | $ | 42 |  | $ | 39 |  | $ | 130 |  | $ | 122 |
Maintenance |  | 2024 |  | 41 |  |  | 38 |  |  | 122 |  |  | 115 |
Money pool interest | (Interest Charges)/Other Income, Net | 2025 | $ | (b) | $ | (b) | $ | (b) | $ | (b)
|  | 2024 |  | (b) |  | (b) |  | (3) |  |  | (2) |
Long-term debt, net - related parties | (Interest Charges) | 2025 | $ | (1) |  | $ | (b) | $ | (2) |  | $ | (b)
|  | 2024 |  | — |  |  | — |  |  | — |  |  | — |

(a)Not applicable.
(b)Amount less than $1 million.
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NOTE 9 – COMMITMENTS AND CONTINGENCIES
We are involved in legal, tax, and regulatory proceedings before various courts, regulatory commissions, authorities, and governmental agencies with respect to matters that arise in the ordinary course of business, some of which involve substantial amounts of money. We believe that the final disposition of these proceedings, except as otherwise disclosed in the notes to our financial statements in this report and in the Form 10-K, will not have a material adverse effect on our results of operations, financial position, or liquidity.
Reference is made to Note 1 – Summary of Significant Accounting Policies, Note 2 – Rate and Regulatory Matters, Note 9 – Callaway Energy Center, Note 13 – Related-party Transactions, and Note 14 – Commitments and Contingencies under Part II, Item 8, of the Form 10-K. See also Note 1 – Summary of Significant Accounting Policies, Note 2 – Rate and Regulatory Matters, Note 8 – Related-party Transactions, and Note 10 – Callaway Energy Center of this report.
Environmental Matters
Our electric generation, transmission, and distribution and natural gas distribution and storage operations must comply with a variety of statutes and regulations relating to the protection of the environment and human health and safety, including permitting programs implemented by federal, state, and local authorities. Such environmental laws regulate air emissions; protect water bodies; regulate the handling and disposal of hazardous substances and waste materials; establish siting and land use requirements; and protect against potential ecological impacts. Complex and lengthy processes are required to obtain and renew approvals, permits, and licenses for new, existing, or modified energy-related facilities. Additionally, the use and handling of various chemicals or hazardous materials require release prevention plans and emergency response procedures.
Environmental regulations impact the electric utility industry and compliance obligations could be costly for Ameren Missouri, which operates coal-fired and natural gas-fired energy centers. Compliance obligations under the Clean Air Act stem from a variety of programs including the NSPS, the MATS, emission allowance programs, the CSAPR, and the National Ambient Air Quality Standards, which are subject to periodic review for certain pollutants. Collectively, these regulations cover a variety of pollutants, such as SO 2, particulate matter, NO x, mercury, toxic metals and acid gases, and CO 2 emissions. To the extent our operations impact surface water bodies, including wetlands, the Clean Water Act requires permitting as well as evaluation of the ecological and biological impact of those operations. Implementation of requirements under the Clean Air Act and the Clean Water Act typically occurs through the issuance of permits by state regulators or resource agencies, and capital expenditures associated with compliance could be significant. The management and disposal of coal ash from our coal-fired energy centers must comply with federal regulations known as the CCR Rule issued under the Resource Conservation and Recovery Act and require the closure of surface impoundments at our coal-fired energy centers along with groundwater monitoring requirements and the implementations of corrective measures if necessary. The combined effects of compliance with existing and future environmental regulations could result in significant capital expenditures, increased operating costs, and the potential for closure or alteration of operations at some of Ameren Missouri’s energy centers. Ameren and Ameren Missouri expect that such compliance costs would be recoverable through rates, subject to MoPSC prudence review, but the timing of costs and their recovery could be subject to regulatory lag.
Additionally, Ameren Missouri’s wind generation facilities may be subject to operating restrictions to limit the impact on protected species. Since 2021, Ameren Missouri’s High Prairie Energy Center has curtailed nighttime operations from April through October to limit impacts on protected species during the critical biological season. The extent and duration of future curtailments are currently unknown as assessment of mitigation technologies is ongoing. Ameren Missouri does not anticipate these operating curtailments will have a material impact on its results of operations, financial position, or liquidity.
Due to proposed rules issued by the EPA in June and July 2025, which are discussed below, Ameren and Ameren Missouri have revised capital expenditure estimates necessary to comply with environmental regulations to a range of $90 million to $120 million from 2025 through 2029. Additional capital expenditures beyond 2029 could be required. This estimate includes surface impoundment closure and corrective action measures required by the 2015 CCR Rule and modifications to cooling water intake structures at existing power plants under Clean Water Act rules in place prior to 2024, all of which are discussed below. The EPA could review and revise compliance requirements. In addition to planned retirements of coal-fired energy centers that were included in Ameren Missouri’s 2025 Change to the 2023 PRP and with respect to the Illinois emissions standards discussed in Note 14 – Commitments and Contingencies under Part II, Item 8, of the Form 10-K, Ameren Missouri’s current plan for compliance with existing air emission regulations includes burning low-sulfur coal and optimizing existing air pollution control equipment. Accordingly, the actual amount of capital expenditures required to comply with existing environmental regulations could vary from the above estimates because of uncertainty as to revisions to regulatory requirements by the EPA and/or state regulators and their timing and varying cost of potential compliance strategies, among other things.
The following sections describe the significant environmental statutes and regulations and environmental enforcement and remediation matters that affect or could affect our operations. The EPA could ultimately revise all or part of such regulations.
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Clean Air Act
Federal and state laws, including the CSAPR, regulate emissions of SO 2 and NO x through the reduction of emissions at their source and the use and retirement of emission allowances available for state budgets. In 2022, the EPA proposed the Good Neighbor Rule to reduce the transport of ozone from power plants by reducing the amount of CSAPR NO x allowances available for compliance. The EPA subsequently rejected state implementation plans proposed by Missouri and other states to comply with the Good Neighbor Rule. The disapprovals for some state implementation plans, including Missouri’s, were stayed by multiple appellate courts, and in 2024, the United States Supreme Court issued a stay of a federal implementation plan. In March 2025, the EPA announced it would take steps to repeal the Good Neighbor Rule and work with states on their implementation plans. Ameren Missouri complies with the current CSAPR requirements by minimizing emissions with low-sulfur coal, operation of two scrubbers at its Sioux Energy Center, and optimization of existing NO x air pollution control equipment. If the EPA repeals the currently stayed Good Neighbor Rule, Ameren Missouri would not expect additional NO x controls at its coal-fired energy centers to be necessary.
CO 2 Emissions Standards
In April 2024, the EPA issued a final rule that sets CO 2 emission standards for existing coal-fired and new natural gas-fired power plants based on the emissions expected from adoption of carbon capture technology and/or natural gas co-firing for coal-fired power plants and carbon capture technology for new natural gas-fired power plants. Affected power plants are required to comply with the rule through a phased-in approach or retire. In June 2025, the EPA issued a proposed rule to repeal all greenhouse gas emissions standards for fossil fuel-fired power plants, including the April 2024 rule. In addition, in July 2025, the EPA announced a proposed rule reconsidering its 2009 Endangerment Finding for greenhouse gas emissions, which was the basis for implementing greenhouse gas emissions standards. The EPA expects to issue final rules by the end of 2025.
MATS
In April 2024, the EPA revised the MATS by establishing a more stringent standard for emissions of particulate matter, as well as requiring the use of continuous emissions monitoring systems. In April 2025, the presidential administration issued a proclamation through which it granted owners of coal-fired energy centers, including Ameren Missouri, a two-year extension of the compliance deadline. As such, the compliance deadline for the Labadie and Sioux energy centers is now set for July 2029. In June 2025, the EPA issued a proposed rule to repeal the April 2024 revisions to the MATS. The EPA expects to issue a final rule by the end of 2025.
NSPS
In November 2024, the EPA issued a proposed rule revising the NSPS to limit emissions of NO x from natural gas-fired stationary CTs. If adopted as proposed, the rule would require such natural gas facilities which began construction after December 13, 2024, to install certain pollution control equipment to limit emissions of NO x. In addition, the EPA proposed to maintain the current limits for SO 2 at such natural gas facilities. As discussed above, in June 2025, the EPA issued a proposed rule to repeal all greenhouse gas emissions standards for fossil fuel-fired power plants, including the NSPS. The EPA expects to issue a final rule by the end of 2025.
Clean Water Act
All of Ameren Missouri’s coal-fired and nuclear energy centers are subject to Clean Water Act requirements to identify measures for reducing the number of aquatic organisms impinged on a power plant’s cooling water intake screens or entrained through the plant’s cooling water system. Cooling water intake requirements are implemented by state regulators through the permit renewal process of each power plant’s water discharge permit. Permits for Ameren Missouri’s coal-fired and nuclear energy centers have been issued or are in the process of renewal.
CCR Management
The EPA’s 2015 CCR Rule establishes requirements for the management and disposal of CCR from coal-fired power plants and has resulted in the closure of surface impoundments at Ameren Missouri’s energy centers, with closures of surface impoundments in process at its Sioux Energy Center and retired Meramec Energy Center. Ameren Missouri plans to substantially complete the closures of remaining surface impoundments by the end of 2026. Ameren Missouri’s CCR management compliance plan includes installation of groundwater monitoring equipment and groundwater treatment facilities. In April 2024, the EPA revised the CCR Rule to impose groundwater monitoring, and corrective action, closure, and post-closure requirements on certain active and inactive CCR surface impoundments and disposal units not previously included in the 2015 CCR Rule. Ameren and Ameren Missouri have AROs of $40 million associated with CCR storage facilities recorded on their respective balance sheets as of September 30, 2025. This amount includes an immaterial incremental ARO related to the 2024 CCR Rule, which may be revised as additional site studies are performed. The EPA could reconsider aspects of the 2015 and 2024 CCR rules. Ameren and Ameren Missouri are monitoring the ongoing legal challenges and regulatory developments but, at this time, cannot predict the final impacts of the 2024 CCR Rule on their results of operations, financial position, and liquidity.
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Remediation
The Ameren Companies are involved in a number of remediation actions to clean up sites impacted by the use or disposal of materials containing hazardous substances. Federal and state laws can require responsible parties to fund remediation regardless of their degree of fault, the legality of original disposal, or the ownership of a disposal site.
As of September 30, 2025, Ameren Illinois has remediated the majority of the 44 former MGP sites in Illinois with an estimated remaining obligation primarily related to three of these former MGP sites at $45 million to $90 million. Ameren and Ameren Illinois recorded a liability of $45 million to represent the estimated minimum obligation for these sites, as no other amount within the range was a better estimate. Ameren and Ameren Illinois cannot estimate the completion dates of the estimated remaining obligation due to site accessibility, among other things.
The scope of the remediation activities at these former MGP sites may increase as remediation efforts continue. Considerable uncertainty remains in these estimates because many site-specific factors can influence the actual costs, including unanticipated underground structures, the degree to which groundwater is impacted, regulatory changes, local ordinances, and site accessibility. The actual costs and timing of completion may vary substantially from these estimates.
The ICC allows Ameren Illinois to recover MGP remediation and related litigation costs from its electric and natural gas utility customers through environmental cost riders that are subject to annual prudence reviews by the ICC.
Our operations or those of our predecessor companies involve the use of, disposal of, and, in appropriate circumstances, the cleanup of substances regulated under environmental laws. Such historical practices may result in future environmental commitments, including additional or more stringent cleanup standards. We are unable to determine whether such historical practices will affect our results of operations, financial position, or liquidity.
NOTE 10 – CALLAWAY ENERGY CENTER
See Note 9 – Callaway Energy Center under Part II, Item 8, of the Form 10-K for information regarding spent nuclear fuel recovery, recovery of decommissioning costs, and the nuclear decommissioning trust fund. The fair value of the trust fund for Ameren Missouri’s Callaway Energy Center is reported as “Nuclear decommissioning trust fund” in Ameren’s and Ameren Missouri’s balance sheets. This amount is legally restricted and may be used only to fund the costs of nuclear decommissioning. Changes in the fair value of the trust fund are recorded as an increase or decrease to the nuclear decommissioning trust fund, with an offsetting adjustment to the related regulatory liability. Ameren and Ameren Missouri have recorded an ARO for the Callaway Energy Center decommissioning costs at fair value, which represents the present value of estimated future cash outflows. Annual decommissioning costs of $7 million have historically been included in the costs used to establish electric rates for Ameren Missouri’s customers. Every three years, the MoPSC requires Ameren Missouri to file an updated cost study and funding analysis for decommissioning its Callaway Energy Center. An updated cost study and funding analysis was filed with the MoPSC in December 2023 and is reflected within the ARO. In May 2025, the MoPSC issued an order that approved a non-unanimous stipulation and agreement between Ameren Missouri and the MoPSC staff that reduced annual customer contributions for funding the Callaway Energy Center decommissioning costs from $7 million to zero, as the trust fund level exceeded the estimated present value of future decommissioning costs at the time of the agreement. This MoPSC order removed Ameren Missouri’s funding obligation effective in June 2025. See Note 13 – Supplemental Information for more information on Ameren Missouri’s AROs.
Insurance
The following table presents insurance coverage at Ameren Missouri’s Callaway Energy Center at September 30, 2025:

Type and Source of Coverage | Most Recent Renewal Date | Maximum Coverages |  | Maximum Assessments for Single Incidents |
Public liability and nuclear worker liability: |  |  |  |  |
American Nuclear Insurers | January 1, 2025 | $ | 500 |  |  | $ | — |  |
Pool participation | (a) | 15,763 |  | (a) | 166 |  | (b)
|  | $ | 16,263 |  | (c) | $ | 166 |  |
Property damage: |  |  |  |  |
NEIL and EMANI | April 1, 2025 | $ | 3,200 |  | (d) | $ | 22 |  | (e)
Accidental outage: |  |  |  |  |
NEIL | April 1, 2025 | $ | 490 |  | (f) | $ | 9 |  | (e)

(a)Provided through mandatory participation in an industrywide retrospective premium assessment program. The maximum coverage available is dependent on the number of United States commercial reactors participating in the program.
(b)Retrospective premium under the Price-Anderson Act. This is subject to retrospective assessment with respect to a covered loss in excess of $500 million in the event of an incident at any licensed United States commercial reactor, payable at $25 million per year.
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(c)Limit of liability for each incident under the Price-Anderson liability provisions of the Atomic Energy Act of 1954, as amended. This limit is subject to change to account for the effects of inflation and changes in the number of licensed power reactors.
(d)NEIL provides $2.7 billion in property damage, stabilization, decontamination, and premature decommissioning insurance for radiation events and $0.7 billion in property damage insurance for nonradiation events. EMANI provides $490 million in property damage insurance for both radiation and nonradiation events.
(e)All NEIL-insured plants could be subject to retrospective assessments should losses exceed the accumulated funds from NEIL.
(f)Accidental outage insurance provides for lost sales in the event of a prolonged accidental outage. Weekly indemnity up to $4.5 million for 52 weeks, which commences after the first 12 weeks of an outage, plus up to $3.6 million per week for a minimum of 71 weeks thereafter for a total not exceeding the policy limit of $490 million. Nonradiation events are limited to $291 million.
The Price-Anderson Act is a federal law that limits the liability for claims from an incident involving any licensed United States commercial nuclear energy center. The limit is based on the number of licensed reactors. The limit of liability and the maximum potential annual payments are adjusted at least every five years for inflation to reflect changes in the Consumer Price Index. The most recent five-year inflationary adjustment became effective in October 2023. Owners of a nuclear reactor cover this exposure through a combination of private insurance and mandatory participation in a financial protection pool, as established by the Price-Anderson Act.
Losses resulting from terrorist attacks on nuclear facilities insured by NEIL are subject to industrywide aggregates, such that terrorist acts against one or more commercial nuclear power plants within a stated time period would be treated as a single event, and the owners of the nuclear power plants would share the limit of liability. NEIL policies have an aggregate limit of $3.2 billion within a 12-month period for radiation events, or $1.8 billion for events not involving radiation contamination, resulting from terrorist attacks. The EMANI policies are not subject to industrywide aggregates in the event of terrorist attacks on nuclear facilities.
If losses from a nuclear incident at the Callaway Energy Center exceed insurance limits, are not covered by insurance, or if coverage is unavailable, Ameren Missouri is at risk for any uninsured losses. If a serious nuclear incident were to occur, it could have a material adverse effect on Ameren’s and Ameren Missouri’s results of operations, financial position, or liquidity.
NOTE 11 – RETIREMENT BENEFITS
The following table presents the components of the net periodic benefit cost (income) incurred for Ameren’s pension and postretirement benefit plans for the three and nine months ended September 30, 2025 and 2024:

| Pension Benefits |  |  | Postretirement Benefits
| Three Months |  | Nine Months |  |  | Three Months |  | Nine Months
| 2025 |  | 2024 |  | 2025 |  | 2024 |  |  | 2025 |  | 2024 |  | 2025 |  | 2024
Service cost(a) | $ | 21 |  |  | $ | 22 |  |  | $ | 62 |  |  | $ | 66 |  |  |  | $ | 3 |  |  | $ | 3 |  |  | $ | 8 |  |  | $ | 9 |
Non-service cost components: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest cost | 58 |  |  | 56 |  |  | 175 |  |  | 167 |  |  |  | 11 |  |  | 11 |  |  | 33 |  |  | 33 |
Expected return on plan assets(b) | (76) |  |  | (82) |  |  | (227) |  |  | (246) |  |  |  | (24) |  |  | (23) |  |  | (71) |  |  | (69) |
Amortization of(b): |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Prior service cost (credit) | — |  |  | — |  |  | — |  |  | — |  |  |  | (1) |  |  | (1) |  |  | (3) |  |  | (3) |
Actuarial (gain) | (9) |  |  | (17) |  |  | (26) |  |  | (50) |  |  |  | (9) |  |  | (9) |  |  | (27) |  |  | (29) |
Total non-service cost components(c) | $ | (27) |  |  | $ | (43) |  |  | $ | (78) |  |  | $ | (129) |  |  |  | $ | (23) |  |  | $ | (22) |  |  | $ | (68) |  |  | $ | (68) |
Net periodic benefit income(d) | $ | (6) |  |  | $ | (21) |  |  | $ | (16) |  |  | $ | (63) |  |  |  | $ | (20) |  |  | $ | (19) |  |  | $ | (60) |  |  | $ | (59) |

(a)Service cost, net of capitalization, is reflected in “Operating Expenses – Other operations and maintenance” on Ameren’s statement of income.
(b)Prior service cost (credit) is amortized on a straight-line basis over the average future service of active participants benefiting under a plan amendment. Net actuarial gains or losses related to the net benefit obligation subject to amortization are amortized on a straight-line basis over 10 years. The difference between the actual and expected return on plan assets is amortized over 4 years.
(c)Non-service cost components are reflected in “Other Income, Net” on Ameren’s consolidated statement of income. See Note 5 – Other Income, Net for additional information.
(d)Does not include the impact of the tracker for the difference between the level of pension and postretirement benefit costs (income) incurred by Ameren Missouri under GAAP and the level of such costs included in customer rates.
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Ameren Missouri and Ameren Illinois are responsible for their respective share of Ameren’s pension and other postretirement costs. The following table presents the respective share of net periodic pension and other postretirement benefit costs (income) incurred for the three and nine months ended September 30, 2025 and 2024:

| Pension Benefits |  |  | Postretirement Benefits
| Three Months |  | Nine Months |  |  | Three Months |  | Nine Months
| 2025 |  | 2024 |  | 2025 |  | 2024 |  |  | 2025 |  | 2024 |  | 2025 |  | 2024
Ameren Missouri(a) | $ | (4) |  |  | $ | (11) |  |  | $ | (11) |  |  | $ | (33) |  |  |  | $ | (7) |  |  | $ | (6) |  |  | $ | (21) |  |  | $ | (20) |
Ameren Illinois | (1) |  |  | (8) |  |  | (3) |  |  | (25) |  |  |  | (13) |  |  | (13) |  |  | (39) |  |  | (39) |
Other | (1) |  |  | (2) |  |  | (2) |  |  | (5) |  |  |  | — |  |  | — |  |  | — |  |  | — |
Ameren(a) | $ | (6) |  |  | $ | (21) |  |  | $ | (16) |  |  | $ | (63) |  |  |  | $ | (20) |  |  | $ | (19) |  |  | $ | (60) |  |  | $ | (59) |

(a)Does not include the impact of the tracker for the difference between the level of pension and postretirement benefit costs (income) incurred by Ameren Missouri under GAAP and the level of such costs included in customer rates.
NOTE 12 – INCOME TAXES
OBBBA
The OBBBA was enacted in July 2025 and includes various income tax provisions, among other things. The OBBBA modified provisions of the IRA related to production and investment tax credits. The new law maintains production and investment tax credits for solar and wind projects that begin construction within one year of the OBBBA’s enactment and are placed in-service by the end of 2030. Projects that begin construction after one year from enactment of the OBBBA but are placed in service by the end of 2027 also remain eligible. The law provides investment tax credits for battery storage projects that begin construction by the end of 2033 and phase out by the end of 2035. Renewable energy projects that begin construction in 2026 and beyond that use a certain threshold percentage of materials from prohibited foreign entities, as defined in the OBBBA, are not eligible for the tax credits. Production tax credits associated with nuclear generation remain unchanged from the IRA and phase out by the end of 2032. Furthermore, the new law continues to allow for transferability of the production and investment tax credits to an unrelated party for cash but is restricted from being transferred to specified foreign entities, as defined in the OBBBA. Ameren is currently evaluating the OBBBA and guidance issued in connection with the OBBBA and does not expect any material impacts on its results of operations, financial position, and liquidity in 2025. Implementation of the OBBBA provisions is subject to additional guidance, regulations, interpretations, amendments, or technical corrections that may be issued by the IRS or United States Department of Treasury.
The following table presents a reconciliation of the federal statutory corporate income tax rate to the effective income tax rate for the three and nine months ended September 30, 2025 and 2024:

| Ameren |  | Ameren Missouri |  | Ameren Illinois |
| 2025 |  | 2024 |  | 2025 |  | 2024 |  | 2025 |  | 2024 |
Three Months |  |  |  |  |  |  |  |  |  |  |  |
Federal statutory corporate income tax rate | 21 | % |  | 21 | % |  | 21 | % |  | 21 | % |  | 21 | % |  | 21 | % |
Increases (decreases) from: |  |  |  |  |  |  |  |  |  |  |  |
Amortization of excess deferred taxes(a) | (7) |  |  | (9) |  |  | (9) |  |  | (15) |  |  | (4) |  |  | (4) |  |
Revaluation of excess deferred income taxes(b) | (7) |  |  | — |  |  | — |  |  | — |  |  | (14) |  |  | — |  |
Amortization of deferred investment tax credit | (1) |  |  | — |  |  | (1) |  |  | — |  |  | — |  |  | — |  |
Renewable and other tax credits(c) | (3) |  |  | (4) |  |  | (7) |  |  | (10) |  |  | — |  |  | — |  |
State tax | 5 |  |  | 4 |  |  | 3 |  |  | 3 |  |  | 7 |  |  | 7 |  |
Depreciation differences | (1) |  |  | — |  |  | (1) |  |  | (1) |  |  | (1) |  |  | — |  |
Other permanent items | — |  |  | (1) |  |  | — |  |  | — |  |  | 1 |  |  | — |  |
Effective income tax rate | 7 | % |  | 11 | % |  | 6 | % |  | (2) | % |  | 10 | % |  | 24 | % |
Nine Months |  |  |  |  |  |  |  |  |  |  |  |
Federal statutory corporate income tax rate | 21 | % |  | 21 | % |  | 21 | % |  | 21 | % |  | 21 | % |  | 21 | % |
Increases (decreases) from: |  |  |  |  |  |  |  |  |  |  |  |
Amortization of excess deferred taxes(a) | (7) |  |  | (8) |  |  | (9) |  |  | (14) |  |  | (4) |  |  | (4) |  |
Revaluation of excess deferred income taxes(b) | (3) |  |  | — |  |  | — |  |  | — |  |  | (4) |  |  | — |  |
Amortization of deferred investment tax credit | (1) |  |  | — |  |  | (1) |  |  | — |  |  | — |  |  | — |  |
Renewable and other tax credits(c) | (3) |  |  | (5) |  |  | (7) |  |  | (10) |  |  | — |  |  | — |  |
State tax | 5 |  |  | 5 |  |  | 3 |  |  | 3 |  |  | 7 |  |  | 7 |  |
Depreciation differences | (1) |  |  | — |  |  | (1) |  |  | (1) |  |  | — |  |  | — |  |
Effective income tax rate | 11 | % |  | 13 | % |  | 6 | % |  | (1) | % |  | 20 | % |  | 24 | % |

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(a)Reflects the amortization of amounts resulting from the revaluation of deferred income taxes subject to regulatory ratemaking, which are being refunded to customers. Deferred income taxes are revalued when federal or state income tax rates change, and the offset to the revaluation of deferred income taxes subject to regulatory ratemaking is recorded to a regulatory asset or liability.
(b)In 2024, the IRS issued a series of private letter rulings to another taxpayer, which provided guidance on applying IRS normalization rules to the calculation of tax benefits applicable to the ratemaking treatment related to net operating loss carryforwards. The rulings concluded that, for ratemaking purposes, net operating loss carryforwards should be reflected on a separate company basis and should not be reduced by payments received for the utilization of losses by other affiliates under a tax allocation agreement. In 2025, the FERC issued an order reflecting implementation of the rules for the other taxpayer who had a similar fact pattern as Ameren Illinois and ATXI. Accordingly, in the third quarter of 2025, Ameren and Ameren Illinois decreased income tax expense by $48 million and $23 million, respectively, to reflect the revaluation of excess deferred income tax regulatory liabilities resulting from TCJA for FERC-regulated jurisdictions pursuant to IRS guidance and recent FERC order.
(c)The benefit of the renewable credits associated with Missouri renewable energy standard compliance is refunded to customers through the RESRAM. The benefit of the renewable credits associated with the production and investment tax credit tracker will be refunded to customers based on MoPSC approval in a regulatory rate review.
NOTE 13 – SUPPLEMENTAL INFORMATION
Cash, Cash Equivalents, and Restricted Cash
The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported within the balance sheets and the statements of cash flows at September 30, 2025, and December 31, 2024:

| September 30, 2025 |  |  | December 31, 2024
Ameren |  | Ameren Missouri |  | Ameren Illinois |  |  | Ameren |  | Ameren Missouri |  | Ameren Illinois
“Cash and cash equivalents” | $ | 9 |  |  | $ | — |  |  | $ | — |  |  |  | $ | 7 |  |  | $ | — |  |  | $ | — |
Restricted cash included in “Other current assets” (a) | 95 |  |  | 86 |  |  | 6 |  |  |  | 15 |  |  | 7 |  |  | 6 |
Restricted cash included in “Other assets” | 324 |  |  | — |  |  | 324 |  |  |  | 296 |  |  | — |  |  | 296 |
Restricted cash included in “Nuclear decommissioning trust fund” | 7 |  |  | 7 |  |  | — |  |  |  | 10 |  |  | 10 |  |  | — |
Total cash, cash equivalents, and restricted cash | $ | 435 |  |  | $ | 93 |  |  | $ | 330 |  |  |  | $ | 328 |  |  | $ | 17 |  |  | $ | 302 |

(a)Included in “Restricted cash” on Ameren Missouri’s balance sheet.
Restricted cash included in “Other current assets” represents funds held by an irrevocable Voluntary Employee Beneficiary Association (VEBA) trust, which provides health care benefits for active employees on Ameren’s, Ameren Missouri’s, and Ameren Illinois’ balance sheets, funds held in an escrow account for programs established as a result of a 2024 court order resolving outstanding claims in the NSR and Clean Air Act litigation on Ameren’s and Ameren Missouri’s balance sheets, and AMF’s restricted cash for payments for securitized utility tariff bonds on Ameren’s and Ameren Missouri’s balance sheets. Restricted cash included in “Other assets” on Ameren’s and Ameren Illinois’ balance sheets primarily represents amounts collected under a cost recovery rider restricted for use in the procurement of renewable energy credits and amounts in a trust fund restricted for the use of funding certain asbestos-related claims.
Accounts Receivable
“Accounts receivable – trade” on Ameren’s and Ameren Illinois’ balance sheets include certain receivables purchased at a discount from alternative retail electric suppliers that elect to participate in the utility consolidated billing program. At September 30, 2025, and December 31, 2024, Ameren’s and Ameren Illinois’ balance sheets included payables for purchased receivables of $55 million and $43 million, respectively. On Ameren’s balance sheet, these amounts were included in “Other current liabilities”.
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The following table provides a reconciliation of the beginning and ending amount of the allowance for doubtful accounts for the three and nine months ended September 30, 2025 and 2024:

| Three Months |  | Nine Months
| 2025 |  | 2024 |  |  | 2025 |  | 2024 |
Ameren: |  |  |  |  |  |  |  |  |
Beginning of period | $ | 39 |  |  | $ | 37 |  |  |  | $ | 30 |  |  | $ | 30 |  |
Bad debt expense | 18 |  |  | 12 |  |  |  | 37 |  |  | 28 |  |
Charged to other accounts(a) | 2 |  |  | 2 |  |  |  | 5 |  |  | 6 |  |
Net write-offs | (21) |  |  | (20) |  |  |  | (34) |  |  | (33) |  |
End of period | $ | 38 |  |  | $ | 31 |  |  |  | $ | 38 |  |  | $ | 31 |  |
Ameren Missouri: |  |  |  |  |  |  |  |  |
Beginning of period | $ | 12 |  |  | $ | 12 |  |  |  | $ | 12 |  |  | $ | 12 |  |
Bad debt expense | 7 |  |  | 3 |  |  |  | 11 |  |  | 8 |  |
Net write-offs | (4) |  |  | (3) |  |  |  | (8) |  |  | (8) |  |
End of period | $ | 15 |  |  | $ | 12 |  |  |  | $ | 15 |  |  | $ | 12 |  |
Ameren Illinois:(b) |  |  |  |  |  |  |  |  |
Beginning of period | $ | 27 |  |  | $ | 25 |  |  |  | $ | 18 |  |  | $ | 18 |  |
Bad debt expense | 11 |  |  | 9 |  |  |  | 26 |  |  | 20 |  |
Charged to other accounts(a) | 2 |  |  | 2 |  |  |  | 5 |  |  | 6 |  |
Net write-offs | (17) |  |  | (17) |  |  |  | (26) |  |  | (25) |  |
End of period | $ | 23 |  |  | $ | 19 |  |  |  | $ | 23 |  |  | $ | 19 |  |

(a)Amounts associated with the allowance for doubtful accounts related to receivables purchased by Ameren Illinois from alternative retail electric suppliers, as required by the Illinois Public Utilities Act.
(b)Ameren Illinois has rate-adjustment mechanisms that allow it to recover the difference between its actual net bad debt write-offs under GAAP, including those associated with receivables purchased from alternative retail electric suppliers, and the amount of net bad debt write-offs included in its base rates. The table above does not include the impact related to the riders.
Supplemental Cash Flow Information
The following table provides noncash financing and investing activity excluded from the statements of cash flows for the nine months ended September 30, 2025 and 2024:

| September 30, 2025 |  | September 30, 2024
Ameren | Ameren Missouri |  | Ameren Illinois | Ameren | Ameren Missouri | Ameren Illinois
Investing: |  |  |  |  |  |  |  |
Accrued capital expenditures, including nuclear fuel expenditures | $ | 412 |  | $ | 277 |  |  | $ | 147 |  |  | $ | 404 |  | $ | 257 |  | $ | 127 |
Net realized and unrealized gain – nuclear decommissioning trust fund | 136 |  | 136 |  |  | — |  |  | 163 |  | 163 |  | — |
Financing: |  |  |  |  |  |  |  |
Issuance of common stock for stock-based compensation | $ | 25 |  | $ | — |  |  | $ | — |  |  | $ | 16 |  | $ | — |  | $ | — |
Issuance of common stock under the DRPlus | 7 |  | — |  |  | — |  |  | 7 |  | — |  | — |

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Asset Retirement Obligations
The following table provides a reconciliation of the beginning and ending carrying amount of AROs for the nine months ended September 30, 2025:

| Ameren Missouri |  | Ameren Illinois |  |  |  | Ameren |
Balance at December 31, 2024 | $ | 823 |  | (a) | $ | 4 |  |  |  | (b) | $ | 827 |  | (a)
Liabilities settled | (7) |  |  | — |  |  |  |  | (7) |  |
Accretion | 27 |  | (c) | — |  |  |  |  | 27 |  | (c)
Change in estimates | 1 |  |  | 1 |  |  |  |  | 2 |  |
Balance at September 30, 2025 | $ | 844 |  | (a) | $ | 5 |  |  |  | (b) | $ | 849 |  | (a)

(a)Balance included $5 million in “Other current liabilities” on the balance sheet as of both September 30, 2025, and December 31, 2024.
(b)Included in “Other deferred credits and liabilities” on the balance sheet.
(c)Accretion expense attributable to Ameren Missouri was recorded as a decrease to regulatory liabilities.
Stock-based Compensation
In the first quarter of 2025, Ameren granted 275,869 performance share units with a grant date fair value of $33 million and 118,213 restricted share units with a grant date fair value of $11 million. Awards vest approximately 3 years after the grant date based on continued employment or on a pro-rata basis upon death or eligible retirement. The performance share units vest based on the achievement of certain specified market performance measures (236,448 performance share units) or clean energy transition targets (39,421 performance share units). The exact number of shares issued pursuant to a performance share unit varies from 0% to 200% of the target award, depending on actual company performance relative to the performance goals.
For the nine months ended September 30, 2025 and 2024, excess tax benefits (deficiencies) associated with the settlement of stock-based compensation awards decreased income tax expense by $1 million and increased income tax expense by $1 million, respectively.
Deferred Compensation
At September 30, 2025, and December 31, 2024, the present value of benefits to be paid for deferred compensation obligations was $80 million and $79 million, respectively, which was primarily reflected in “Other deferred credits and liabilities” on Ameren’s consolidated balance sheet.
Operating Revenues
As of September 30, 2025 and 2024, our remaining performance obligations for contracts with a term greater than one year were immaterial. The Ameren Companies elected not to disclose the aggregate amount of the transaction price allocated to the performance obligations that are unsatisfied as of the end of the reporting period for contracts with an initial expected term of one year or less.
See Note 14 – Segment Information for disaggregated revenue information.
Excise Taxes
Ameren Missouri and Ameren Illinois collect from their customers excise taxes, including municipal and state excise taxes and gross receipts taxes that are levied on the sale or distribution of natural gas and electricity. The following table presents the excise taxes recorded on a gross basis in “Operating Revenues – Electric,” “Operating Revenues – Natural gas” and “Operating Expenses – Taxes other than income taxes” on the statements of income for the three and nine months ended September 30, 2025 and 2024:

| Three Months |  | Nine Months
| 2025 |  | 2024 |  | 2025 |  | 2024
Ameren Missouri | $ | 69 |  |  | $ | 60 |  |  | $ | 150 |  |  | $ | 136 |
Ameren Illinois | 30 |  |  | 29 |  |  | 104 |  |  | 94 |
Ameren | $ | 99 |  |  | $ | 89 |  |  | $ | 254 |  |  | $ | 230 |

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Earnings per Share
The following table reconciles the basic weighted-average number of common shares outstanding to the diluted weighted-average number of common shares outstanding for the three and nine months ended September 30, 2025 and 2024:

| Three Months |  | Nine Months
| 2025 |  | 2024 |  | 2025 |  | 2024
Weighted-average Common Shares Outstanding – Basic | 270.4 |  |  | 266.8 |  |  | 270.2 |  |  | 266.6 |
Assumed settlement of performance share units and restricted stock units | 0.8 |  |  | 0.4 |  |  | 0.9 |  |  | 0.3 |
Dilutive effect of forward sale agreements | 1.0 |  |  | 0.1 |  |  | 0.6 |  |  | — |
Weighted-average Common Shares Outstanding – Diluted(a) | 272.2 |  |  | 267.3 |  |  | 271.7 |  |  | 266.9 |

(a)There was an immaterial number of anti-dilutive performance share units excluded from the earnings per diluted share calculations for the three and nine months ended September 30, 2025 and 2024. Outstanding forward sale agreements as of September 30, 2025 and 2024 that were anti-dilutive for the nine months ended September 30, 2025 and the three and nine months ended September 30, 2024 were excluded from the earnings per diluted share calculation as calculated using the treasury stock method. For additional information about the outstanding forward sale agreements, see Note 4 – Long-term Debt and Equity Financings.
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NOTE 14 – SEGMENT INFORMATION
The following tables present revenues, net income attributable to common shareholders, and capital expenditures by segment at Ameren and Ameren Illinois for the three and nine months ended September 30, 2025 and 2024. Ameren, Ameren Missouri, and Ameren Illinois management review segment capital expenditure information rather than any individual or total asset amount. For additional information about our segments, see Note 16 – Segment Information under Part II, Item 8, of the Form 10-K.
Ameren

| Ameren Missouri |  | Ameren Illinois Electric Distribution |  | Ameren Illinois Natural Gas |  | Ameren Transmission |  | Other |  | Intersegment Eliminations |  | Ameren |
Three Months 2025: |  |  |  |  |  |  |  |  |  |  |  |  |  |
External revenues | $ | 1,696 |  |  | $ | 698 |  |  | $ | 117 |  |  | $ | 188 |  |  | $ | — |  |  | $ | — |  |  | $ | 2,699 |  |
Intersegment revenues | 9 |  |  | 1 |  |  | — |  |  | 52 |  |  | — |  |  | (62) |  |  | — |  |
Revenue | 1,705 |  |  | 699 |  |  | 117 |  |  | 240 |  |  | — |  |  | (62) |  |  | 2,699 |  |
Fuel and purchased power(a) | (487) |  |  | (330) |  |  | — |  |  | — |  |  | — |  |  | 49 |  |  | (768) |  |
Natural gas purchased for resale(a) | (6) |  |  | — |  |  | (19) |  |  | — |  |  | — |  |  | — |  |  | (25) |  |
Other operations and maintenance expenses(a) | (260) |  |  | (171) |  |  | (55) |  |  | (19) |  |  | (10) |  |  | 13 |  |  | (502) |  |
Other segment items |  |  |  |  |  |  |  |  |  |  |  |  |  |
Depreciation and amortization | (239) |  |  | (92) |  |  | (33) |  |  | (49) |  |  | (2) |  |  | — |  |  | (415) |  |
Taxes other than income taxes | (122) |  |  | (22) |  |  | (15) |  |  | (3) |  |  | (2) |  |  | — |  |  | (164) |  |
Other income (expense), net | 45 |  |  | 20 |  |  | 4 |  |  | (3) |  |  | 11 |  |  | (1) |  |  | 76 |  |
Interest charges | (85) |  |  | (28) |  |  | (16) |  |  | (31) |  |  | (49) |  |  | 1 |  |  | (208) |  |
Income taxes (benefit) | (32) |  |  | (19) |  |  | 4 |  |  | 16 |  |  | (21) |  |  | — |  |  | (52) |  |
Noncontrolling interests – preferred stock dividends | (1) |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | (1) |  |
Net income (loss) attributable to Ameren common shareholders | 518 |  |  | 57 |  |  | (13) |  |  | 151 |  | (b) | (73) |  |  | — |  |  | 640 |  |
Interest income | 3 |  |  | 6 |  |  | — |  |  | 1 |  |  | 1 |  |  | (1) |  |  | 10 |  |
Capital expenditures | 548 |  |  | 163 |  |  | 78 |  |  | 174 |  |  | 1 |  |  | 24 |  |  | 988 |  |
Three Months 2024: |  |  |  |  |  |  |  |  |  |  |  |  |  |
External revenues | $ | 1,333 |  |  | $ | 551 |  |  | $ | 121 |  |  | $ | 168 |  |  | $ | — |  |  | $ | — |  |  | $ | 2,173 |  |
Intersegment revenues | 9 |  |  | 1 |  |  | — |  |  | 42 |  |  | — |  |  | (52) |  |  | — |  |
Revenue | 1,342 |  |  | 552 |  |  | 121 |  |  | 210 |  |  | — |  |  | (52) |  |  | 2,173 |  |
Fuel and purchased power(a) | (334) |  |  | (204) |  |  | — |  |  | — |  |  | — |  |  | 39 |  |  | (499) |  |
Natural gas purchased for resale(a) | (4) |  |  | — |  |  | (26) |  |  | — |  |  | — |  |  | — |  |  | (30) |  |
Other operations and maintenance expenses(a) | (288) |  |  | (163) |  |  | (51) |  |  | (19) |  |  | (12) |  |  | 13 |  |  | (520) |  |
Other segment items |  |  |  |  |  |  |  |  |  |  |  |  |  |
Depreciation and amortization | (220) |  |  | (92) |  |  | (32) |  |  | (42) |  |  | (2) |  |  | — |  |  | (388) |  |
Taxes other than income taxes | (109) |  |  | (21) |  |  | (14) |  |  | (2) |  |  | (4) |  |  | — |  |  | (150) |  |
Other income (expense), net | 51 |  |  | 23 |  |  | 6 |  |  | 8 |  |  | 16 |  |  | (3) |  |  | 101 |  |
Interest charges | (62) |  |  | (25) |  |  | (16) |  |  | (31) |  |  | (42) |  |  | 3 |  |  | (173) |  |
Income taxes (benefit) | 6 |  |  | (14) |  |  | 2 |  |  | (34) |  |  | (17) |  |  | — |  |  | (57) |  |
Noncontrolling interests – preferred stock dividends | (1) |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | (1) |  |
Net income (loss) attributable to Ameren common shareholders | 381 |  |  | 56 |  |  | (10) |  |  | 90 |  | (b) | (61) |  |  | — |  |  | 456 |  |
Interest income | 2 |  |  | 6 |  |  | 1 |  |  | — |  |  | 2 |  |  | (3) |  |  | 8 |  |
Capital expenditures | 735 |  |  | 152 |  |  | 83 |  |  | 174 |  |  | 2 |  |  | (9) |  |  | 1,137 |  |

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| Ameren Missouri |  | Ameren Illinois Electric Distribution |  | Ameren Illinois Natural Gas |  | Ameren Transmission |  | Other |  | Intersegment Eliminations |  | Ameren |
Nine Months 2025: |  |  |  |  |  |  |  |  |  |  |  |  |  |
External revenues | $ | 3,978 |  |  | $ | 1,838 |  |  | $ | 686 |  |  | $ | 515 |  |  | $ | — |  |  | $ | — |  |  | $ | 7,017 |  |
Intersegment revenues | 24 |  |  | 6 |  |  | — |  |  | 143 |  |  | — |  |  | (173) |  |  | — |  |
Revenue | 4,002 |  |  | 1,844 |  |  | 686 |  |  | 658 |  |  | — |  |  | (173) |  |  | 7,017 |  |
Fuel and purchased power(a) | (1,431) |  |  | (765) |  |  | — |  |  | — |  |  | — |  |  | 132 |  |  | (2,064) |  |
Natural gas purchased for resale(a) | (45) |  |  | — |  |  | (188) |  |  | — |  |  | — |  |  | — |  |  | (233) |  |
Other operations and maintenance expenses(a) | (748) |  |  | (493) |  |  | (165) |  |  | (56) |  |  | (26) |  |  | 41 |  |  | (1,447) |  |
Other segment items |  |  |  |  |  |  |  |  |  |  |  |  |  |
Depreciation and amortization | (642) |  |  | (276) |  |  | (98) |  |  | (146) |  |  | (6) |  |  | — |  |  | (1,168) |  |
Taxes other than income taxes | (300) |  |  | (63) |  |  | (60) |  |  | (7) |  |  | (9) |  |  | — |  |  | (439) |  |
Other income (expense), net | 135 |  |  | 66 |  |  | 14 |  |  | 14 |  |  | 31 |  |  | (3) |  |  | 257 |  |
Interest charges | (215) |  |  | (80) |  |  | (47) |  |  | (89) |  |  | (142) |  |  | 3 |  |  | (570) |  |
Income (taxes) benefit | (43) |  |  | (48) |  |  | (37) |  |  | (48) |  |  | 31 |  |  | — |  |  | (145) |  |
Noncontrolling interests – preferred stock dividends | (3) |  |  | (1) |  |  | — |  |  | — |  |  | — |  |  | — |  |  | (4) |  |
Net income (loss) attributable to Ameren common shareholders | 710 |  |  | 184 |  |  | 105 |  |  | 326 |  | (b) | (121) |  |  | — |  |  | 1,204 |  |
Interest income | 7 |  |  | 22 |  |  | — |  |  | 2 |  |  | 3 |  |  | (3) |  |  | 31 |  |
Capital expenditures | 1,873 |  |  | 483 |  |  | 225 |  |  | 505 |  |  | 6 |  |  | 26 |  |  | 3,118 |  |
Nine Months 2024: |  |  |  |  |  |  |  |  |  |  |  |  |  |
External revenues | $ | 2,980 |  |  | $ | 1,566 |  |  | $ | 660 |  |  | $ | 476 |  |  | $ | — |  |  | $ | — |  |  | $ | 5,682 |  |
Intersegment revenues | 25 |  |  | 1 |  |  | — |  |  | 110 |  |  | — |  |  | (136) |  |  | — |  |
Revenue | 3,005 |  |  | 1,567 |  |  | 660 |  |  | 586 |  |  | — |  |  | (136) |  |  | 5,682 |  |
Fuel and purchased power(a) | (689) |  |  | (564) |  |  | — |  |  | — |  |  | — |  |  | 99 |  |  | (1,154) |  |
Natural gas purchased for resale(a) | (41) |  |  | — |  |  | (173) |  |  | — |  |  | — |  |  | — |  |  | (214) |  |
Other operations and maintenance expenses(a) | (789) |  |  | (452) |  |  | (168) |  |  | (54) |  |  | (29) |  |  | 37 |  |  | (1,455) |  |
Other segment items |  |  |  |  |  |  |  |  |  |  |  |  |  |
Depreciation and amortization | (623) |  |  | (278) |  |  | (98) |  |  | (121) |  |  | (5) |  |  | — |  |  | (1,125) |  |
Taxes other than income taxes | (287) |  |  | (57) |  |  | (55) |  |  | (6) |  |  | (11) |  |  | — |  |  | (416) |  |
Other income (expense), net | 144 |  |  | 72 |  |  | 20 |  |  | 14 |  |  | 54 |  |  | (11) |  |  | 293 |  |
Interest charges | (187) |  |  | (73) |  |  | (46) |  |  | (89) |  |  | (108) |  |  | 11 |  |  | (492) |  |
Income (taxes) benefit | 4 |  |  | (41) |  |  | (38) |  |  | (89) |  |  | 24 |  |  | — |  |  | (140) |  |
Noncontrolling interests – preferred stock dividends | (3) |  |  | (1) |  |  | — |  |  | — |  |  | — |  |  | — |  |  | (4) |  |
Net income (loss) attributable to Ameren common shareholders | 534 |  |  | 173 |  |  | 102 |  |  | 241 |  | (b) | (75) |  |  | — |  |  | 975 |  |
Interest income | 7 |  |  | 21 |  |  | 1 |  |  | 1 |  |  | 10 |  |  | (11) |  |  | 29 |  |
Capital expenditures | 1,839 |  |  | 468 |  |  | 202 |  |  | 515 |  |  | 6 |  |  | (1) |  |  | 3,029 |  |

(a)Significant segment expense that is regularly provided to the CODMs. Intersegment expenses are included within the amounts shown.
(b)Ameren Transmission earnings reflect an allocation of financing costs from Ameren (parent)
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Ameren Illinois

| Ameren Illinois Electric Distribution |  | Ameren Illinois Natural Gas |  | Ameren Illinois Transmission |  | Intersegment Eliminations |  | Ameren Illinois
Three Months 2025: |  |  |  |  |  |  |  |  |
External revenues | $ | 699 |  |  | $ | 117 |  |  | $ | 130 |  |  | $ | — |  |  | $ | 946 |
Intersegment revenues | — |  |  | — |  |  | 46 |  |  | (46) |  |  | — |
Revenue | 699 |  |  | 117 |  |  | 176 |  |  | (46) |  |  | 946 |
Purchased power(a) | (330) |  |  | — |  |  | — |  |  | 46 |  |  | (284) |
Natural gas purchased for resale(a) | — |  |  | (19) |  |  | — |  |  | — |  |  | (19) |
Other operations and maintenance expenses(a) | (171) |  |  | (55) |  |  | (15) |  |  | — |  |  | (241) |
Other segment items |  |  |  |  |  |  |  |  |
Depreciation and amortization | (92) |  |  | (33) |  |  | (37) |  |  | — |  |  | (162) |
Taxes other than income taxes | (22) |  |  | (15) |  |  | (1) |  |  | — |  |  | (38) |
Other income, net | 20 |  |  | 4 |  |  | 6 |  |  | — |  |  | 30 |
Interest charges | (28) |  |  | (16) |  |  | (23) |  |  | — |  |  | (67) |
Income taxes | (19) |  |  | 4 |  |  | (2) |  |  | — |  |  | (17) |
Net income (loss) available to common shareholder | 57 |  |  | (13) |  |  | 104 |  |  | — |  |  | 148 |
Interest income | 6 |  |  | — |  |  | 1 |  |  | — |  |  | 7 |
Capital expenditures | 163 |  |  | 78 |  |  | 144 |  |  | — |  |  | 385 |
Three Months 2024: |  |  |  |  |  |  |  |  |
External revenues | $ | 552 |  |  | $ | 121 |  |  | $ | 120 |  |  | $ | — |  |  | $ | 793 |
Intersegment revenues | — |  |  | — |  |  | 35 |  |  | (35) |  |  | — |
Revenue | 552 |  |  | 121 |  |  | 155 |  |  | (35) |  |  | 793 |
Purchased power(a) | (204) |  |  | — |  |  | — |  |  | 35 |  |  | (169) |
Natural gas purchased for resale(a) | — |  |  | (26) |  |  | — |  |  | — |  |  | (26) |
Other operations and maintenance expenses(a) | (163) |  |  | (51) |  |  | (15) |  |  | — |  |  | (229) |
Other segment items |  |  |  |  |  |  |  |  |
Depreciation and amortization | (92) |  |  | (32) |  |  | (31) |  |  | — |  |  | (155) |
Taxes other than income taxes | (21) |  |  | (14) |  |  | (2) |  |  | — |  |  | (37) |
Other income, net | 23 |  |  | 6 |  |  | 8 |  |  | — |  |  | 37 |
Interest charges | (25) |  |  | (16) |  |  | (22) |  |  | — |  |  | (63) |
Income taxes | (14) |  |  | 2 |  |  | (25) |  |  | — |  |  | (37) |
Net income (loss) available to common shareholder | 56 |  |  | (10) |  |  | 68 |  |  | — |  |  | 114 |
Interest income | 6 |  |  | 1 |  |  | — |  |  | — |  |  | 7 |
Capital expenditures | 152 |  |  | 83 |  |  | 139 |  |  | — |  |  | 374 |
Nine Months 2025: |  |  |  |  |  |  |  |  |
External revenues | $ | 1,844 |  |  | $ | 686 |  |  | $ | 359 |  |  | $ | — |  |  | $ | 2,889 |
Intersegment revenues | — |  |  | — |  |  | 123 |  |  | (123) |  |  | — |
Revenue | 1,844 |  |  | 686 |  |  | 482 |  |  | (123) |  |  | 2,889 |
Purchased power(a) | (765) |  |  | — |  |  | — |  |  | 123 |  |  | (642) |
Natural gas purchased for resale(a) | — |  |  | (188) |  |  | — |  |  |  |  | (188) |
Other operations and maintenance expenses(a) | (493) |  |  | (165) |  |  | (44) |  |  |  |  | (702) |
Other segment items |  |  |  |  |  |  |  |  |
Depreciation and amortization | (276) |  |  | (98) |  |  | (110) |  |  |  |  | (484) |
Taxes other than income taxes | (63) |  |  | (60) |  |  | (3) |  |  |  |  | (126) |
Other income, net | 66 |  |  | 14 |  |  | 21 |  |  |  |  | 101 |
Interest charges | (80) |  |  | (47) |  |  | (65) |  |  |  |  | (192) |
Income taxes | (48) |  |  | (37) |  |  | (49) |  |  |  |  | (134) |
Noncontrolling interests – preferred stock dividends | (1) |  |  | — |  |  | — |  |  |  |  | (1) |
Net income available to common shareholder | 184 |  |  | 105 |  |  | 232 |  |  | — |  |  | 521 |
Interest income | 22 |  |  | — |  |  | 2 |  |  | — |  |  | 24 |
Capital expenditures | 483 |  |  | 225 |  |  | 419 |  |  | — |  |  | 1,127 |

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| Ameren Illinois Electric Distribution |  | Ameren Illinois Natural Gas |  | Ameren Illinois Transmission |  | Intersegment Eliminations |  | Ameren Illinois
Nine Months 2024: |  |  |  |  |  |  |  |  |
External revenues | $ | 1,567 |  |  | $ | 660 |  |  | $ | 332 |  |  | $ | — |  |  | $ | 2,559 |
Intersegment revenues | — |  |  | — |  |  | 90 |  |  | (90) |  |  | — |
Revenue | 1,567 |  |  | 660 |  |  | 422 |  |  | (90) |  |  | 2,559 |
Purchased power(a) | (564) |  |  | — |  |  | — |  |  | 90 |  |  | (474) |
Natural gas purchased for resale(a) | — |  |  | (173) |  |  | — |  |  |  |  | (173) |
Other operations and maintenance expenses(a) | (452) |  |  | (168) |  |  | (43) |  |  |  |  | (663) |
Other segment items |  |  |  |  |  |  |  |  |
Depreciation and amortization | (278) |  |  | (98) |  |  | (86) |  |  |  |  | (462) |
Taxes other than income taxes | (57) |  |  | (55) |  |  | (4) |  |  |  |  | (116) |
Other income, net | 72 |  |  | 20 |  |  | 13 |  |  |  |  | 105 |
Interest charges | (73) |  |  | (46) |  |  | (59) |  |  |  |  | (178) |
Income taxes | (41) |  |  | (38) |  |  | (65) |  |  |  |  | (144) |
Noncontrolling interests – preferred stock dividends | (1) |  |  | — |  |  | — |  |  |  |  | (1) |
Net income available to common shareholder | 173 |  |  | 102 |  |  | 178 |  |  | — |  |  | 453 |
Interest income | 21 |  |  | 1 |  |  | — |  |  | — |  |  | 22 |
Capital expenditures | 468 |  |  | 202 |  |  | 421 |  |  | — |  |  | 1,091 |

(a)Significant segment expense that is regularly provided to the CODMs. Intersegment expenses are included within the amounts shown.
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The following tables present disaggregated revenues by segment at Ameren and Ameren Illinois for the three and nine months ended September 30, 2025 and 2024. Economic factors affect the nature, timing, amount, and uncertainty of revenues and cash flows in a similar manner across customer classes. Revenues from alternative revenue programs have a similar distribution among customer classes as revenues from contracts with customers. Other revenues not associated with contracts with customers are presented in the Other customer classification, along with electric transmission, off-system sales, and capacity revenues.
Ameren

| Ameren Missouri |  | Ameren Illinois Electric Distribution |  | Ameren Illinois Natural Gas |  | Ameren Transmission |  |  |  | Intersegment Eliminations |  | Ameren |
Three Months 2025: |  |  |  |  |  |  |  |  |  |  |  |  |  |
Residential | $ | 702 |  |  | $ | 469 |  |  | $ | — |  |  | $ | — |  |  |  |  | $ | — |  |  | $ | 1,171 |  |
Commercial | 537 |  |  | 235 |  |  | — |  |  | — |  |  |  |  | — |  |  | 772 |  |
Industrial | 119 |  |  | 46 |  |  | — |  |  | — |  |  |  |  | — |  |  | 165 |  |
Other | 327 |  |  | (51) |  | (a) | — |  |  | 240 |  |  |  |  | (61) |  |  | 455 |  |
Total electric revenues | $ | 1,685 |  |  | $ | 699 |  |  | $ | — |  |  | $ | 240 |  |  |  |  | $ | (61) |  |  | $ | 2,563 |  |
Residential | $ | 9 |  |  | $ | — |  |  | $ | 70 |  |  | $ | — |  |  |  |  | $ | — |  |  | $ | 79 |  |
Commercial | 5 |  |  | — |  |  | 21 |  |  | — |  |  |  |  | — |  |  | 26 |  |
Industrial | — |  |  | — |  |  | 2 |  |  | — |  |  |  |  | — |  |  | 2 |  |
Other | 6 |  |  | — |  |  | 24 |  |  | — |  |  |  |  | (1) |  |  | 29 |  |
Total natural gas revenues | $ | 20 |  |  | $ | — |  |  | $ | 117 |  |  | $ | — |  |  |  |  | $ | (1) |  |  | $ | 136 |  |
Total revenues(b) | $ | 1,705 |  |  | $ | 699 |  |  | $ | 117 |  |  | $ | 240 |  |  |  |  | $ | (62) |  |  | $ | 2,699 |  |
Three Months 2024: |  |  |  |  |  |  |  |  |  |  |  |  |  |
Residential | $ | 590 |  |  | $ | 339 |  |  | $ | — |  |  | $ | — |  |  |  |  | $ | — |  |  | $ | 929 |  |
Commercial | 465 |  |  | 184 |  |  | — |  |  | — |  |  |  |  | — |  |  | 649 |  |
Industrial | 108 |  |  | 38 |  |  | — |  |  | — |  |  |  |  | — |  |  | 146 |  |
Other | 161 |  |  | (9) |  | (a) | — |  |  | 210 |  |  |  |  | (51) |  |  | 311 |  |
Total electric revenues | $ | 1,324 |  |  | $ | 552 |  |  | $ | — |  |  | $ | 210 |  |  |  |  | $ | (51) |  |  | $ | 2,035 |  |
Residential | $ | 9 |  |  | $ | — |  |  | $ | 77 |  |  | $ | — |  |  |  |  | $ | — |  |  | $ | 86 |  |
Commercial | 5 |  |  | — |  |  | 19 |  |  | — |  |  |  |  | — |  |  | 24 |  |
Industrial | — |  |  | — |  |  | 2 |  |  | — |  |  |  |  | — |  |  | 2 |  |
Other | 4 |  |  | — |  |  | 23 |  |  | — |  |  |  |  | (1) |  |  | 26 |  |
Total natural gas revenues | $ | 18 |  |  | $ | — |  |  | $ | 121 |  |  | $ | — |  |  |  |  | $ | (1) |  |  | $ | 138 |  |
Total revenues(b) | $ | 1,342 |  |  | $ | 552 |  |  | $ | 121 |  |  | $ | 210 |  |  |  |  | $ | (52) |  |  | $ | 2,173 |  |
Nine Months 2025: |  |  |  |  |  |  |  |  |  |  |  |  |  |
Residential | $ | 1,483 |  |  | $ | 1,132 |  |  | $ | — |  |  | $ | — |  |  |  |  | $ | — |  |  | $ | 2,615 |  |
Commercial | 1,154 |  |  | 596 |  |  | — |  |  | — |  |  |  |  | — |  |  | 1,750 |  |
Industrial | 269 |  |  | 144 |  |  | — |  |  | — |  |  |  |  | — |  |  | 413 |  |
Other | 987 |  |  | (28) |  | (a) | — |  |  | 658 |  |  |  |  | (172) |  |  | 1,445 |  |
Total electric revenues | $ | 3,893 |  |  | $ | 1,844 |  |  | $ | — |  |  | $ | 658 |  |  |  |  | $ | (172) |  |  | $ | 6,223 |  |
Residential | $ | 65 |  |  | $ | — |  |  | $ | 486 |  |  | $ | — |  |  |  |  | $ | — |  |  | $ | 551 |  |
Commercial | 29 |  |  | — |  |  | 126 |  |  | — |  |  |  |  | — |  |  | 155 |  |
Industrial | 3 |  |  | — |  |  | 9 |  |  | — |  |  |  |  | — |  |  | 12 |  |
Other | 12 |  |  | — |  |  | 65 |  |  | — |  |  |  |  | (1) |  |  | 76 |  |
Total natural gas revenues | $ | 109 |  |  | $ | — |  |  | $ | 686 |  |  | $ | — |  |  |  |  | $ | (1) |  |  | $ | 794 |  |
Total revenues(b) | $ | 4,002 |  |  | $ | 1,844 |  |  | $ | 686 |  |  | $ | 658 |  |  |  |  | $ | (173) |  |  | $ | 7,017 |  |

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| Ameren Missouri |  | Ameren Illinois Electric Distribution |  | Ameren Illinois Natural Gas |  | Ameren Transmission |  |  |  | Intersegment Eliminations |  | Ameren |
Nine Months 2024: |  |  |  |  |  |  |  |  |  |  |  |  |  |
Residential | $ | 1,326 |  |  | $ | 947 |  |  | $ | — |  |  | $ | — |  |  |  |  | $ | — |  |  | $ | 2,273 |  |
Commercial | 1,048 |  |  | 512 |  |  | — |  |  | — |  |  |  |  | — |  |  | 1,560 |  |
Industrial | 246 |  |  | 130 |  |  | — |  |  | — |  |  |  |  | — |  |  | 376 |  |
Other | 282 |  |  | (22) |  | (a) | — |  |  | 586 |  |  |  |  | (135) |  |  | 711 |  |
Total electric revenues | $ | 2,902 |  |  | $ | 1,567 |  |  | $ | — |  |  | $ | 586 |  |  |  |  | $ | (135) |  |  | $ | 4,920 |  |
Residential | $ | 62 |  |  | $ | — |  |  | $ | 466 |  |  | $ | — |  |  |  |  | $ | — |  |  | $ | 528 |  |
Commercial | 26 |  |  | — |  |  | 111 |  |  | — |  |  |  |  | — |  |  | 137 |  |
Industrial | 3 |  |  | — |  |  | 7 |  |  | — |  |  |  |  | — |  |  | 10 |  |
Other | 12 |  |  | — |  |  | 76 |  |  | — |  |  |  |  | (1) |  |  | 87 |  |
Total natural gas revenues | $ | 103 |  |  | $ | — |  |  | $ | 660 |  |  | $ | — |  |  |  |  | $ | (1) |  |  | $ | 762 |  |
Total revenues(b) | $ | 3,005 |  |  | $ | 1,567 |  |  | $ | 660 |  |  | $ | 586 |  |  |  |  | $ | (136) |  |  | $ | 5,682 |  |

(a)Includes over-recoveries of various riders.
(b)The following table presents increases/(decreases) in revenues from alternative revenue programs and other revenues not from contracts with customers for the three and nine months ended September 30, 2025 and 2024:

| Ameren Missouri |  | Ameren Illinois Electric Distribution |  | Ameren Illinois Natural Gas |  | Ameren Transmission |  | Intersegment Eliminations |  | Ameren |
Three Months 2025: |  |  |  |  |  |  |  |  |  |  |  |
Revenues from alternative revenue programs | $ | — |  |  | $ | (187) |  |  | $ | (10) |  |  | $ | (12) |  |  | $ | — |  |  | $ | (209) |  |
Other revenues not from contracts with customers | 2 |  |  | 3 |  |  | — |  |  | — |  |  | — |  |  | 5 |  |
Three Months 2024: |  |  |  |  |  |  |  |  |  |  |  |
Revenues from alternative revenue programs | $ | — |  |  | $ | (144) |  |  | $ | (9) |  |  | $ | (2) |  |  | $ | — |  |  | $ | (155) |  |
Other revenues not from contracts with customers | 2 |  |  | 2 |  |  | — |  |  | — |  |  | — |  |  | 4 |  |
Nine Months 2025: |  |  |  |  |  |  |  |  |  |  |  |
Revenues from alternative revenue programs | $ | (4) |  |  | $ | (174) |  |  | $ | (6) |  |  | $ | (21) |  |  | $ | — |  |  | $ | (205) |  |
Other revenues not from contracts with customers | 5 |  |  | 11 |  |  | 2 |  |  | — |  |  | (4) |  |  | 14 |  |
Nine Months 2024: |  |  |  |  |  |  |  |  |  |  |  |
Revenues from alternative revenue programs | $ | (7) |  |  | $ | (83) |  |  | $ | 10 |  |  | $ | 11 |  |  | $ | — |  |  | $ | (69) |  |
Other revenues not from contracts with customers | 4 |  |  | 5 |  |  | 2 |  |  | — |  |  | — |  |  | 11 |  |

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Ameren Illinois

| Ameren Illinois Electric Distribution |  | Ameren Illinois Natural Gas |  | Ameren Illinois Transmission |  | Intersegment Eliminations |  | Ameren Illinois |
Three Months 2025: |  |  |  |  |  |  |  |  |  |
Residential | $ | 469 |  |  | $ | 70 |  |  | $ | — |  |  | $ | — |  |  | $ | 539 |  |
Commercial | 235 |  |  | 21 |  |  | — |  |  | — |  |  | 256 |  |
Industrial | 46 |  |  | 2 |  |  | — |  |  | — |  |  | 48 |  |
Other | (51) |  | (a) | 24 |  |  | 176 |  |  | (46) |  |  | 103 |  |
Total revenues(b) | $ | 699 |  |  | $ | 117 |  |  | $ | 176 |  |  | $ | (46) |  |  | $ | 946 |  |
Three Months 2024: |  |  |  |  |  |  |  |  |  |
Residential | $ | 339 |  |  | $ | 77 |  |  | $ | — |  |  | $ | — |  |  | $ | 416 |  |
Commercial | 184 |  |  | 19 |  |  | — |  |  | — |  |  | 203 |  |
Industrial | 38 |  |  | 2 |  |  | — |  |  | — |  |  | 40 |  |
Other | (9) |  | (a) | 23 |  |  | 155 |  |  | (35) |  |  | 134 |  |
Total revenues(b) | $ | 552 |  |  | $ | 121 |  |  | $ | 155 |  |  | $ | (35) |  |  | $ | 793 |  |
Nine Months 2025: |  |  |  |  |  |  |  |  |  |
Residential | $ | 1,132 |  |  | $ | 486 |  |  | $ | — |  |  | $ | — |  |  | $ | 1,618 |  |
Commercial | 596 |  |  | 126 |  |  | — |  |  | — |  |  | 722 |  |
Industrial | 144 |  |  | 9 |  |  | — |  |  | — |  |  | 153 |  |
Other | (28) |  | (a) | 65 |  |  | 482 |  |  | (123) |  |  | 396 |  |
Total revenues(b) | $ | 1,844 |  |  | $ | 686 |  |  | $ | 482 |  |  | $ | (123) |  |  | $ | 2,889 |  |
Nine Months 2024: |  |  |  |  |  |  |  |  |  |
Residential | $ | 947 |  |  | $ | 466 |  |  | $ | — |  |  | $ | — |  |  | $ | 1,413 |  |
Commercial | 512 |  |  | 111 |  |  | — |  |  | — |  |  | 623 |  |
Industrial | 130 |  |  | 7 |  |  | — |  |  | — |  |  | 137 |  |
Other | (22) |  | (a) | 76 |  |  | 422 |  |  | (90) |  |  | 386 |  |
Total revenues(b) | $ | 1,567 |  |  | $ | 660 |  |  | $ | 422 |  |  | $ | (90) |  |  | $ | 2,559 |  |

(a)Includes over-recoveries of various riders.
(b)The following table presents increases/(decreases) in revenues from alternative revenue programs and other revenues not from contracts with customers for the Ameren Illinois segments for the three and nine months ended September 30, 2025 and 2024:

| Ameren Illinois Electric Distribution |  | Ameren Illinois Natural Gas |  | Ameren Illinois Transmission |  | Ameren Illinois
Three Months 2025: |  |  |  |  |  |  |
Revenues from alternative revenue programs | $ | (187) |  |  | $ | (10) |  |  | $ | (12) |  |  | $ | (209) |
Other revenues not from contracts with customers | 3 |  |  | — |  |  | — |  |  | 3 |
Three Months 2024: |  |  |  |  |  |  |
Revenues from alternative revenue programs | $ | (144) |  |  | $ | (9) |  |  | $ | (1) |  |  | $ | (154) |
Other revenues not from contracts with customers | 2 |  |  | — |  |  | — |  |  | 2 |
Nine Months 2025: |  |  |  |  |  |  |
Revenues from alternative revenue programs | $ | (174) |  |  | $ | (6) |  |  | $ | (20) |  |  | $ | (200) |
Other revenues not from contracts with customers | 11 |  |  | 2 |  |  | — |  |  | 13 |
Nine Months 2024: |  |  |  |  |  |  |
Revenues from alternative revenue programs | $ | (83) |  |  | $ | 10 |  |  | $ | 9 |  |  | $ | (64) |
Other revenues not from contracts with customers | 5 |  |  | 2 |  |  | — |  |  | 7 |

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ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS.
The following discussion should be read in conjunction with the financial statements contained in this Form 10-Q, as well as Management’s Discussion and Analysis of Financial Condition and Results of Operations and Risk Factors contained in the Form 10-K. We intend for this discussion to provide the reader with information that will assist in understanding our financial statements, the changes in certain key items in those financial statements, and the primary factors that accounted for those changes, as well as how certain accounting principles affect our financial statements. The discussion also provides information about the financial results of our business segments to provide a better understanding of how those segments and their results affect the financial condition and results of operations of Ameren as a whole. Also see the Glossary of Terms and Abbreviations at the front of this report and in the Form 10-K.
Ameren, headquartered in St. Louis, Missouri, is a public utility holding company whose primary assets are its equity interests in its subsidiaries. Ameren’s subsidiaries are separate, independent legal entities with separate businesses, assets, and liabilities. Dividends on Ameren’s common stock and the payment of expenses by Ameren depend on distributions made to it by its subsidiaries. Ameren’s principal subsidiaries are listed below. Ameren also has other subsidiaries that conduct other activities, such as providing shared services.
•Ameren Missouri operates a rate-regulated electric generation, transmission, and distribution business and a rate-regulated natural gas distribution business in Missouri.
•Ameren Illinois operates rate-regulated electric transmission, electric distribution, and natural gas distribution businesses in Illinois.
•ATXI operates a FERC rate-regulated electric transmission business within the MISO.
Ameren’s and Ameren Missouri’s financial statements are prepared on a consolidated basis and therefore include the accounts of their majority-owned subsidiaries. All intercompany transactions have been eliminated. Ameren Illinois has no subsidiaries. All tabular dollar amounts are in millions, unless otherwise indicated.
In addition to presenting results of operations and earnings amounts in total, we present certain information in cents per share. These amounts reflect factors that directly affect Ameren’s earnings. We believe this per share information helps readers to understand the impact of these factors on Ameren’s earnings per diluted share.
OVERVIEW
Net income attributable to Ameren common shareholders in the three months ended September 30, 2025, was $640 million, or $2.35 per diluted share, compared with $456 million, or $1.70 per diluted share, in the year-ago period. Net income attributable to Ameren common shareholders in the nine months ended September 30, 2025, was $1,204 million, or $4.43 per diluted share, compared with $975 million, or $3.65 per diluted share, in the year-ago period. Net income was favorably affected for the three and nine months ended September 30, 2025, 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 due to the revaluation of excess deferred income tax regulatory liabilities. Earnings were also favorably affected for the three and nine months ended September 30, 2025, by decreased other operations and maintenance expenses not subject to formula rates, riders, or trackers, largely 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 for the three and nine months ended September 30, 2025, by increased retail electric sales volumes at Ameren Missouri, primarily due to warmer July temperatures and colder winter temperatures in 2025 and growth in retail electric sales and 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 for the three and nine months ended September 30, 2025, by increased financing costs, primarily resulting from higher interest rates on higher debt balances at Ameren (parent) and Ameren Missouri 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 storm costs, higher energy center maintenance expenses, and higher transmission and distribution vegetation management costs.
Ameren’s strategic plan includes investing in rate-regulated energy infrastructure, enhancing regulatory frameworks and advocating for responsible policies, and optimizing operating performance to capitalize on opportunities to benefit our customers, communities, shareholders, and the environment. Ameren remains focused on disciplined cost management and strategic capital allocation. Ameren invested $3.1 billion in its rate-regulated businesses in the nine months ended September 30, 2025.
In April 2025, Missouri Senate Bill 4 was enacted and 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 high-demand 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.
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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 authorizes 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 November 2025, Ameren Missouri updated its May 2025 request with the MoPSC 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. A decision by the MoPSC is expected by February 2026.
In June 2025, Ameren Missouri filed for a CCN with the MoPSC to construct the Big Hollow Natural Gas (800-MW facility) and the Big Hollow Battery Energy Storage (400-MW facility) projects. In August 2025, Ameren Missouri filed for a CCN to construct the Reform Solar Project (250-MW facility). Ameren Missouri expects decisions by the MoPSC in the first half of 2026.
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 authorizes 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 February 2025, 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 2025. 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 $16.2 billion over the five-year period from 2025 through 2029, 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 April 2025, Ameren Illinois filed for a reconciliation adjustment to its 2024 electric distribution service revenue requirement with the ICC. In September 2025, Ameren Illinois filed a revised reconciliation adjustment, requesting recovery of $60 million. The adjustment reflects Ameren Illinois’ actual 2024 recoverable costs, 2024 year-end rate base, and a capital structure composed of 50% common equity. In September 2025, the ICC staff submitted its calculation of the reconciliation adjustment, recommending recovery of $47 million. The ICC staff’s recommendation excluded an asset associated with other postretirement benefits from the rate base. An ICC decision in this proceeding is required by December 2025, and any approved adjustment would be collected from customers in 2026.
In January 2025, Ameren Illinois filed a request with the ICC seeking approval to increase its annual revenues for natural gas delivery service. In July 2025, Ameren Illinois filed a revised request seeking to increase its annual revenues by $135 million. The request is based on a 10.7% ROE, a capital structure composed of 52% common equity, and a rate base of $3.3 billion. Ameren Illinois used a 2026 future test year in this proceeding. In August 2025, the ICC staff filed a revised recommendation to increase Ameren Illinois’ annual revenues for natural gas delivery service by $104 million. The recommendation is based on a 9.93% ROE, a capital structure composed of 50% common equity, and a rate base of $3.2 billion. In addition, in August 2025, the Illinois Attorney General's office recommended an increase to annual revenues for natural gas delivery service of $55 million, based on a 9.45% ROE, a capital structure composed of 50% common equity, and a rate base of $3.0 billion. In October 2025, the administrative law judge issued a proposed order for an increase to annual revenues of $91 million. The order was consistent with the ICC staff’s recommendation with the exception of the exclusion of the non-service cost component of the net periodic benefit income related to other postretirement benefits in the annual revenue requirement. A decision by the ICC in this proceeding is required by early December 2025, with new rates expected to be effective in early December 2025.
In May 2025, Ameren Illinois filed its annual electric energy-efficiency formula rate update to increase its annual revenues by $12 million with the ICC. In August 2025, the ICC staff filed a recommendation supporting Ameren Illinois’ requested increase. An ICC decision in this proceeding is required by December 2025, with new rates effective in January 2026.
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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.
For further information on the matters discussed above, see Note 2 – Rate and Regulatory Matters under Part I, Item 1, of this report, and the Outlook section below.
RESULTS OF OPERATIONS
Our results of operations and financial position are affected by many factors. Economic conditions, energy-efficiency investments by our customers and by us, technological advances, distributed generation, and the actions of key customers can significantly affect the demand for our services. Ameren and Ameren Missouri results are also affected by seasonal fluctuations in winter heating and summer cooling demands and by weather conditions, such as storms, as well as by energy center maintenance outages. Additionally, fluctuations in interest rates and conditions in the capital and credit markets affect our cost of borrowing, our pension and postretirement benefits costs, the cash surrender value of COLI, and the asset value of Ameren Missouri’s nuclear decommissioning trust fund. Almost all of Ameren’s revenues are subject to state or federal regulation. This regulation has a material impact on the rates we charge customers for our services. Our results of operations, financial position, and liquidity are affected by our ability to align our overall spending, both operating and capital, with the frameworks established by our regulators. See Note 2 – Rate and Regulatory Matters under Part I, Item 1, of this report and Note 2 – Rate and Regulatory Matters under Part II, Item 8, of the Form 10-K for additional information regarding Ameren Missouri’s, Ameren Illinois’, and ATXI’s regulatory mechanisms.
Ameren Missouri principally uses coal and enriched uranium for fuel in its electric generation operations and purchases natural gas for its customers. Ameren Illinois purchases power and natural gas for its customers. The prices for these commodities can fluctuate significantly because of the global economic and political environment, weather, supply, demand, and many other factors. We have natural gas cost recovery mechanisms for our Illinois and Missouri natural gas distribution businesses, a purchased power cost recovery mechanism for Ameren Illinois’ electric distribution business, and a FAC for Ameren Missouri’s electric business.
We employ various risk management strategies to reduce our exposure to commodity risk and other risks inherent in our business. The reliability of Ameren Missouri’s energy centers and our transmission and distribution systems, and the level and timing of operations and maintenance costs and capital investment, are key factors that we seek to manage in order to optimize our results of operations, financial position, and liquidity.
Earnings Summary
The following table presents a summary of Ameren’s earnings for the three and nine months ended September 30, 2025 and 2024:

| Three Months |  | Nine Months
| 2025 |  | 2024 |  | 2025 |  | 2024
Net income attributable to Ameren common shareholders | $ | 640 |  |  | $ | 456 |  |  | $ | 1,204 |  |  | $ | 975 |
Earnings per common share – diluted | 2.35 |  |  | 1.70 |  |  | 4.43 |  |  | 3.65 |

Net income attributable to Ameren common shareholders increased $184 million and earnings per diluted share increased 65 cents in the three months ended September 30, 2025, compared with the year-ago period. The increase was due to net income increases of $137 million, $61 million, and $1 million, at Ameren Missouri, Ameren Transmission and Ameren Illinois Electric Distribution, respectively. These increases were partially offset by an increase in net loss of $3 million at Ameren Illinois Natural Gas and $12 million for activity not reported as part of a segment, primarily at Ameren (parent).
Net income attributable to Ameren common shareholders increased $229 million and earnings per diluted share increased 78 cents in the nine months ended September 30, 2025, compared with the year-ago period. The increase was due to net income increases of $176 million, $85 million, $11 million, and $3 million at Ameren Missouri, Ameren Transmission, Ameren Illinois Electric Distribution, and Ameren Illinois Natural Gas, respectively. These increases were partially offset by an increase in net loss of $46 million for activity not reported as part of a segment, primarily at Ameren (parent).
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Earnings per diluted share were favorably affected in the three and nine months ended September 30, 2025, compared to the year-ago periods (except where a specific period is referenced), by:
•increased base rate revenues at Ameren Missouri effective June 1, 2025, pursuant to the April 2025 MoPSC electric rate order and a lower base level of expenses, partially offset by financing costs otherwise recoverable under the PISA and RESRAM, depreciation and amortization on property, plant, and equipment previously eligible for deferral under the PISA and RESRAM, and the net recovery for amounts associated with the reduction in sales volumes resulting from MEEIA programs (28 cents and 36 cents per share, respectively);
•decreased income tax expense at Ameren Transmission resulting from the revaluation of excess deferred income tax regulatory liabilities, resulting from TCJA for FERC-regulated jurisdictions, related to ratemaking treatment of net operating loss carryforwards by affiliates under a tax allocation agreement, see Note 12 – Income Taxes under Part I, Item 1, of this report for additional information (18 cents per share for both periods);
•the absence of a 2024 charge recorded by Ameren Missouri, included in other operation and maintenance expenses, related to a settlement agreement with the United States Department of Justice that resolved all outstanding claims in the NSR and Clean Air Act litigation related to the Rush Island Energy Center (13 cents and 17 cents per share, respectively);
•increased retail electric sales volumes at Ameren Missouri, excluding customer energy-efficiency programs, primarily due to warmer July temperatures and colder winter temperatures compared to the prior-year periods, and growth in retail electric sales (estimated at 15 cents and 17 cents per share, respectively);
•increased base rate revenues at Ameren Missouri for the inclusion of previously deferred interest charges pursuant to the April 2025 MoPSC electric rate order effective June 1, 2025, and higher interest deferrals related to infrastructure investments associated with the PISA and RESRAM (4 cents and 13 cents per share, respectively);
•increased rate base investments at Ameren Transmission and Ameren Illinois Electric Distribution (5 cents and 11 cents per share, respectively);
•the absence of the October 2024 FERC order reducing the allowed base ROE for FERC regulated transmission rate base and required refunds for certain prior periods under the MISO tariff, which increased Ameren Transmission earnings (4 cents per share for both periods); and
•a higher allowance for equity funds used during construction at Ameren Transmission (4 cents per share in the nine months ended September 30, 2025).
Earnings per diluted share were unfavorably affected in the three and nine months ended September 30, 2025, compared to the year-ago periods, by:
•increased financing costs primarily due to higher interest rates on higher debt balances at Ameren (parent) and Ameren Missouri (6 cents and 20 cents per share, respectively);
•increased other operations and maintenance expenses not subject to formula rates, riders, or trackers, excluding a 2024 charge related to the NSR and Clean Air Act litigation discussed above, largely because of higher storm costs, higher energy center maintenance expense, and higher transmission and distribution expenditures for vegetation management costs at Ameren Missouri (6 cents and 9 cents per share, respectively);
•increased weighted-average basic common shares outstanding resulting from issuances of common shares (3 cents and 6 cents per share, respectively); and
•increased losses related to equity method investments (2 cents and 5 cents per share, respectively).
The cents per share variances above are presented based on the weighted-average basic common shares outstanding in the three and nine months ended September 30, 2024, and do not reflect the impact of dilution on earnings per share, unless otherwise noted. The amounts above other than variances related to income taxes have been presented net of income taxes using Ameren’s 2025 blended federal and state statutory tax rate of 26%. For additional details regarding the Ameren Companies’ results of operations, including explanations of Operating Revenues for both Electric Revenues and Natural Gas Revenues; Fuel and Purchased Power Expenses; Other Operations and Maintenance Expenses; Depreciation and Amortization Expenses; Taxes Other Than Income Taxes; Other Income, Net; Interest Charges; and Income Taxes, see the major headings below.
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Below is Ameren’s table of income statement components by segment for the three and nine months ended September 30, 2025 and 2024:

| Ameren Missouri |  | Ameren Illinois Electric Distribution |  | Ameren Illinois Natural Gas |  | Ameren Transmission |  | Other / Intersegment Eliminations |  | Ameren
Three Months 2025: |  |  |  |  |  |  |  |  |  |  |
Electric revenues | $ | 1,685 |  |  | $ | 699 |  |  | $ | — |  |  | $ | 240 |  |  | $ | (61) |  |  | $ | 2,563 |
Natural gas revenues | 20 |  |  | — |  |  | 117 |  |  | — |  |  | (1) |  |  | 136 |
Fuel and purchased power | (487) |  |  | (330) |  |  | — |  |  | — |  |  | 49 |  |  | (768) |
Natural gas purchased for resale | (6) |  |  | — |  |  | (19) |  |  | — |  |  | — |  |  | (25) |
Other operations and maintenance expenses | (260) |  |  | (171) |  |  | (55) |  |  | (19) |  |  | 3 |  |  | (502) |
Depreciation and amortization expenses | (239) |  |  | (92) |  |  | (33) |  |  | (49) |  |  | (2) |  |  | (415) |
Taxes other than income taxes | (122) |  |  | (22) |  |  | (15) |  |  | (3) |  |  | (2) |  |  | (164) |
Operating income (loss) | 591 |  |  | 84 |  |  | (5) |  |  | 169 |  |  | (14) |  |  | 825 |
Other income (expense), net | 45 |  |  | 20 |  |  | 4 |  |  | (3) |  |  | 10 |  |  | 76 |
Interest charges | (85) |  |  | (28) |  |  | (16) |  |  | (31) |  |  | (48) |  |  | (208) |
Income (taxes) benefit | (32) |  |  | (19) |  |  | 4 |  |  | 16 |  |  | (21) |  |  | (52) |
Net income (loss) | 519 |  |  | 57 |  |  | (13) |  |  | 151 |  |  | (73) |  |  | 641 |
Noncontrolling interests – preferred stock dividends | (1) |  |  | — |  |  | — |  |  | — |  |  | — |  |  | (1) |
Net income (loss) attributable to Ameren common shareholders | $ | 518 |  |  | $ | 57 |  |  | $ | (13) |  |  | $ | 151 |  |  | $ | (73) |  |  | $ | 640 |
Three Months 2024: |  |  |  |  |  |  |  |  |  |  |
Electric revenues | $ | 1,324 |  |  | $ | 552 |  |  | $ | — |  |  | $ | 210 |  |  | $ | (51) |  |  | $ | 2,035 |
Natural gas revenues | 18 |  |  | — |  |  | 121 |  |  | — |  |  | (1) |  |  | 138 |
Fuel and purchased power | (334) |  |  | (204) |  |  | — |  |  | — |  |  | 39 |  |  | (499) |
Natural gas purchased for resale | (4) |  |  | — |  |  | (26) |  |  | — |  |  | — |  |  | (30) |
Other operations and maintenance expenses | (288) |  |  | (163) |  |  | (51) |  |  | (19) |  |  | 1 |  |  | (520) |
Depreciation and amortization expenses | (220) |  |  | (92) |  |  | (32) |  |  | (42) |  |  | (2) |  |  | (388) |
Taxes other than income taxes | (109) |  |  | (21) |  |  | (14) |  |  | (2) |  |  | (4) |  |  | (150) |
Operating income (loss) | 387 |  |  | 72 |  |  | (2) |  |  | 147 |  |  | (18) |  |  | 586 |
Other income, net | 51 |  |  | 23 |  |  | 6 |  |  | 8 |  |  | 13 |  |  | 101 |
Interest charges | (62) |  |  | (25) |  |  | (16) |  |  | (31) |  |  | (39) |  |  | (173) |
Income (taxes) benefit | 6 |  |  | (14) |  |  | 2 |  |  | (34) |  |  | (17) |  |  | (57) |
Net income (loss) | 382 |  |  | 56 |  |  | (10) |  |  | 90 |  |  | (61) |  |  | 457 |
Noncontrolling interests – preferred stock dividends | (1) |  |  | — |  |  | — |  |  | — |  |  | — |  |  | (1) |
Net income (loss) attributable to Ameren common shareholders | $ | 381 |  |  | $ | 56 |  |  | $ | (10) |  |  | $ | 90 |  |  | $ | (61) |  |  | $ | 456 |

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| Ameren Missouri |  | Ameren Illinois Electric Distribution |  | Ameren Illinois Natural Gas |  | Ameren Transmission |  | Other / Intersegment Eliminations |  | Ameren
Nine Months 2025: |  |  |  |  |  |  |  |  |  |  |
Electric revenues | $ | 3,893 |  |  | $ | 1,844 |  |  | $ | — |  |  | $ | 658 |  |  | $ | (172) |  |  | $ | 6,223 |
Natural gas revenues | 109 |  |  | — |  |  | 686 |  |  | — |  |  | (1) |  |  | 794 |
Fuel and purchased power | (1,431) |  |  | (765) |  |  | — |  |  | — |  |  | 132 |  |  | (2,064) |
Natural gas purchased for resale | (45) |  |  | — |  |  | (188) |  |  | — |  |  | — |  |  | (233) |
Other operations and maintenance expenses | (748) |  |  | (493) |  |  | (165) |  |  | (56) |  |  | 15 |  |  | (1,447) |
Depreciation and amortization expenses | (642) |  |  | (276) |  |  | (98) |  |  | (146) |  |  | (6) |  |  | (1,168) |
Taxes other than income taxes | (300) |  |  | (63) |  |  | (60) |  |  | (7) |  |  | (9) |  |  | (439) |
Operating income (loss) | 836 |  |  | 247 |  |  | 175 |  |  | 449 |  |  | (41) |  |  | 1,666 |
Other income, net | 135 |  |  | 66 |  |  | 14 |  |  | 14 |  |  | 28 |  |  | 257 |
Interest charges | (215) |  |  | (80) |  |  | (47) |  |  | (89) |  |  | (139) |  |  | (570) |
Income (taxes) benefit | (43) |  |  | (48) |  |  | (37) |  |  | (48) |  |  | 31 |  |  | (145) |
Net income (loss) | 713 |  |  | 185 |  |  | 105 |  |  | 326 |  |  | (121) |  |  | 1,208 |
Noncontrolling interests – preferred stock dividends | (3) |  |  | (1) |  |  | — |  |  | — |  |  | — |  |  | (4) |
Net income (loss) attributable to Ameren common shareholders | $ | 710 |  |  | $ | 184 |  |  | $ | 105 |  |  | $ | 326 |  |  | $ | (121) |  |  | $ | 1,204 |
Nine Months 2024: |  |  |  |  |  |  |  |  |  |  |
Electric revenues | $ | 2,902 |  |  | $ | 1,567 |  |  | $ | — |  |  | $ | 586 |  |  | $ | (135) |  |  | $ | 4,920 |
Natural gas revenues | 103 |  |  | — |  |  | 660 |  |  | — |  |  | (1) |  |  | 762 |
Fuel and purchased power | (689) |  |  | (564) |  |  | — |  |  | — |  |  | 99 |  |  | (1,154) |
Natural gas purchased for resale | (41) |  |  | — |  |  | (173) |  |  | — |  |  | — |  |  | (214) |
Other operations and maintenance expenses | (789) |  |  | (452) |  |  | (168) |  |  | (54) |  |  | 8 |  |  | (1,455) |
Depreciation and amortization expenses | (623) |  |  | (278) |  |  | (98) |  |  | (121) |  |  | (5) |  |  | (1,125) |
Taxes other than income taxes | (287) |  |  | (57) |  |  | (55) |  |  | (6) |  |  | (11) |  |  | (416) |
Operating income (loss) | 576 |  |  | 216 |  |  | 166 |  |  | 405 |  |  | (45) |  |  | 1,318 |
Other income, net | 144 |  |  | 72 |  |  | 20 |  |  | 14 |  |  | 43 |  |  | 293 |
Interest charges | (187) |  |  | (73) |  |  | (46) |  |  | (89) |  |  | (97) |  |  | (492) |
Income (taxes) benefit | 4 |  |  | (41) |  |  | (38) |  |  | (89) |  |  | 24 |  |  | (140) |
Net income (loss) | 537 |  |  | 174 |  |  | 102 |  |  | 241 |  |  | (75) |  |  | 979 |
Noncontrolling interests – preferred stock dividends | (3) |  |  | (1) |  |  | — |  |  | — |  |  | — |  |  | (4) |
Net income (loss) attributable to Ameren common shareholders | $ | 534 |  |  | $ | 173 |  |  | $ | 102 |  |  | $ | 241 |  |  | $ | (75) |  |  | $ | 975 |

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Below is Ameren Illinois’ table of income statement components by segment for the three and nine months ended September 30, 2025 and 2024:

| Ameren Illinois Electric Distribution |  | Ameren Illinois Natural Gas |  | Ameren Illinois Transmission |  | Other / Intersegment Eliminations |  | Ameren Illinois
Three Months 2025: |  |  |  |  |  |  |  |  |
Electric revenues | $ | 699 |  |  | $ | — |  |  | $ | 176 |  |  | $ | (46) |  |  | $ | 829 |
Natural gas revenues | — |  |  | 117 |  |  | — |  |  | — |  |  | 117 |
Purchased power | (330) |  |  | — |  |  | — |  |  | 46 |  |  | (284) |
Natural gas purchased for resale | — |  |  | (19) |  |  | — |  |  | — |  |  | (19) |
Other operations and maintenance expenses | (171) |  |  | (55) |  |  | (15) |  |  | — |  |  | (241) |
Depreciation and amortization expenses | (92) |  |  | (33) |  |  | (37) |  |  | — |  |  | (162) |
Taxes other than income taxes | (22) |  |  | (15) |  |  | (1) |  |  | — |  |  | (38) |
Operating income (loss) | 84 |  |  | (5) |  |  | 123 |  |  | — |  |  | 202 |
Other income, net | 20 |  |  | 4 |  |  | 6 |  |  | — |  |  | 30 |
Interest charges | (28) |  |  | (16) |  |  | (23) |  |  | — |  |  | (67) |
Income (taxes) benefit | (19) |  |  | 4 |  |  | (2) |  |  | — |  |  | (17) |
Net income (loss) attributable to Ameren common shareholders | $ | 57 |  |  | $ | (13) |  |  | $ | 104 |  |  | $ | — |  |  | $ | 148 |
Three Months 2024: |  |  |  |  |  |  |  |  |
Electric revenues | $ | 552 |  |  | $ | — |  |  | $ | 155 |  |  | $ | (35) |  |  | $ | 672 |
Natural gas revenues | — |  |  | 121 |  |  | — |  |  | — |  |  | 121 |
Purchased power | (204) |  |  | — |  |  | — |  |  | 35 |  |  | (169) |
Natural gas purchased for resale | — |  |  | (26) |  |  | — |  |  | — |  |  | (26) |
Other operations and maintenance expenses | (163) |  |  | (51) |  |  | (15) |  |  | — |  |  | (229) |
Depreciation and amortization expenses | (92) |  |  | (32) |  |  | (31) |  |  | — |  |  | (155) |
Taxes other than income taxes | (21) |  |  | (14) |  |  | (2) |  |  | — |  |  | (37) |
Operating income (loss) | 72 |  |  | (2) |  |  | 107 |  |  | — |  |  | 177 |
Other income, net | 23 |  |  | 6 |  |  | 8 |  |  | — |  |  | 37 |
Interest charges | (25) |  |  | (16) |  |  | (22) |  |  | — |  |  | (63) |
Income (taxes) benefit | (14) |  |  | 2 |  |  | (25) |  |  | — |  |  | (37) |
Net income (loss) attributable to Ameren common shareholders | $ | 56 |  |  | $ | (10) |  |  | $ | 68 |  |  | $ | — |  |  | $ | 114 |
Nine Months 2025: |  |  |  |  |  |  |  |  |
Electric revenues | $ | 1,844 |  |  | $ | — |  |  | $ | 482 |  |  | $ | (123) |  |  | $ | 2,203 |
Natural gas revenues | — |  |  | 686 |  |  | — |  |  | — |  |  | 686 |
Purchased power | (765) |  |  | — |  |  | — |  |  | 123 |  |  | (642) |
Natural gas purchased for resale | — |  |  | (188) |  |  | — |  |  | — |  |  | (188) |
Other operations and maintenance expenses | (493) |  |  | (165) |  |  | (44) |  |  | — |  |  | (702) |
Depreciation and amortization expenses | (276) |  |  | (98) |  |  | (110) |  |  | — |  |  | (484) |
Taxes other than income taxes | (63) |  |  | (60) |  |  | (3) |  |  | — |  |  | (126) |
Operating income | 247 |  |  | 175 |  |  | 325 |  |  | — |  |  | 747 |
Other income, net | 66 |  |  | 14 |  |  | 21 |  |  | — |  |  | 101 |
Interest charges | (80) |  |  | (47) |  |  | (65) |  |  | — |  |  | (192) |
Income taxes | (48) |  |  | (37) |  |  | (49) |  |  | — |  |  | (134) |
Net income | 185 |  |  | 105 |  |  | 232 |  |  | — |  |  | 522 |
Preferred stock dividends | (1) |  |  | — |  |  | — |  |  | — |  |  | (1) |
Net income attributable to common shareholder | $ | 184 |  |  | $ | 105 |  |  | $ | 232 |  |  | $ | — |  |  | $ | 521 |

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| Ameren Illinois Electric Distribution |  | Ameren Illinois Natural Gas |  | Ameren Illinois Transmission |  | Other / Intersegment Eliminations |  | Ameren Illinois
Nine Months 2024: |  |  |  |  |  |  |  |  |
Electric revenues | $ | 1,567 |  |  | $ | — |  |  | $ | 422 |  |  | $ | (90) |  |  | $ | 1,899 |
Natural gas revenues | — |  |  | 660 |  |  | — |  |  | — |  |  | 660 |
Purchased power | (564) |  |  | — |  |  | — |  |  | 90 |  |  | (474) |
Natural gas purchased for resale | — |  |  | (173) |  |  | — |  |  | — |  |  | (173) |
Other operations and maintenance expenses | (452) |  |  | (168) |  |  | (43) |  |  | — |  |  | (663) |
Depreciation and amortization expenses | (278) |  |  | (98) |  |  | (86) |  |  | — |  |  | (462) |
Taxes other than income taxes | (57) |  |  | (55) |  |  | (4) |  |  | — |  |  | (116) |
Operating income | 216 |  |  | 166 |  |  | 289 |  |  | — |  |  | 671 |
Other income, net | 72 |  |  | 20 |  |  | 13 |  |  | — |  |  | 105 |
Interest charges | (73) |  |  | (46) |  |  | (59) |  |  | — |  |  | (178) |
Income taxes | (41) |  |  | (38) |  |  | (65) |  |  | — |  |  | (144) |
Net income | 174 |  |  | 102 |  |  | 178 |  |  | — |  |  | 454 |
Preferred stock dividends | (1) |  |  | — |  |  | — |  |  | — |  |  | (1) |
Net income attributable to common shareholder | $ | 173 |  |  | $ | 102 |  |  | $ | 178 |  |  | $ | — |  |  | $ | 453 |

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Operating Revenues
The following table presents the increases (decreases) by Ameren segment for electric and natural gas revenues for the three and nine months ended September 30, 2025, compared with the year-ago periods:

Three Months | Ameren Missouri |  | Ameren Illinois Electric Distribution |  | Ameren Illinois Natural Gas |  | Ameren Transmission(a) |  | Other /Intersegment Eliminations |  | Ameren |  |  |  |  |
Electric revenue change: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Base rates (estimate)(b) | $ | 143 |  |  | $ | 23 |  |  | $ | — |  |  | $ | 30 |  |  | $ | — |  |  | $ | 196 |  |  |  |  |  |
Effect of weather (estimate)(c) | 37 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 37 |  |  |  |  |  |
Retail sales volumes and changes in customer usage patterns (excluding the estimated effects of weather and MEEIA) | 23 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 23 |  |  |  |  |  |
MEEIA performance incentives | 3 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 3 |  |  |  |  |  |
Off-system sales, capacity, transmission, and FAC revenues, net | 146 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 146 |  |  |  |  |  |
Ameren Illinois energy-efficiency program investment revenues | — |  |  | 6 |  |  | — |  |  | — |  |  | — |  |  | 6 |  |  |  |  |  |
Securitized utility tariff bond surcharges | 11 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 11 |  |  |  |  |  |
RESRAM(d) | (10) |  |  | — |  |  | — |  |  | — |  |  | — |  |  | (10) |  |  |  |  |  |
Other | 4 |  |  | 3 |  |  | — |  |  | — |  |  | — |  |  | 7 |  |  |  |  |  |
Cost recovery mechanisms – offset in fuel and purchased power(e) | (1) |  |  | 126 |  |  | — |  |  | — |  |  | (10) |  |  | 115 |  |  |  |  |  |
Other cost recovery mechanisms(f) | 5 |  |  | (11) |  |  | — |  |  | — |  |  | — |  |  | (6) |  |  |  |  |  |
Total electric revenue change | $ | 361 |  |  | $ | 147 |  |  | $ | — |  |  | $ | 30 |  |  | $ | (10) |  |  | $ | 528 |  |  |  |  |  |
Natural gas revenue change: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Base rates (estimate) | $ | 1 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | 1 |  |  |  |  |  |
Other | (1) |  |  | — |  |  | — |  |  | — |  |  | — |  |  | (1) |  |  |  |  |  |
Cost recovery mechanisms – offset in natural gas purchased for resale(e) | 2 |  |  | — |  |  | (7) |  |  | — |  |  | — |  |  | (5) |  |  |  |  |  |
Other cost recovery mechanisms(f) | — |  |  | — |  |  | 3 |  |  | — |  |  | — |  |  | 3 |  |  |  |  |  |
Total natural gas revenue change | $ | 2 |  |  | $ | — |  |  | $ | (4) |  |  | $ | — |  |  | $ | — |  |  | $ | (2) |  |  |  |  |  |
Nine Months |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Electric revenue change: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Base rates (estimate)(b) | $ | 187 |  |  | $ | 54 |  |  | $ | — |  |  | $ | 72 |  |  | $ | — |  |  | $ | 313 |  |  |  |  |  |
Effect of weather (estimate)(c) | 48 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 48 |  |  |  |  |  |
Retail sales volumes and changes in customer usage patterns (excluding the estimated effects of weather and MEEIA) | 23 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 23 |  |  |  |  |  |
MEEIA performance incentives | 4 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 4 |  |  |  |  |  |
Off-system sales, capacity, and FAC revenues, net | 745 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 745 |  |  |  |  |  |
Ameren Illinois energy-efficiency program investment revenues | — |  |  | 10 |  |  | — |  |  | — |  |  | — |  |  | 10 |  |  |  |  |  |
Rush Island Energy Center base rate revenue deferral | (26) |  |  | — |  |  | — |  |  | — |  |  | — |  |  | (26) |  |  |  |  |  |
Securitized utility tariff bond surcharges | 35 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 35 |  |  |  |  |  |
RESRAM(d) | (17) |  |  | — |  |  | — |  |  | — |  |  | — |  |  | (17) |  |  |  |  |  |
Other | 9 |  |  | 12 |  |  | — |  |  | — |  |  | (4) |  |  | 17 |  |  |  |  |  |
Cost recovery mechanisms – offset in fuel and purchased power(e) | (19) |  |  | 201 |  |  | — |  |  | — |  |  | (33) |  |  | 149 |  |  |  |  |  |
Other cost recovery mechanisms(f) | 2 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 2 |  |  |  |  |  |
Total electric revenue change | $ | 991 |  |  | $ | 277 |  |  | $ | — |  |  | $ | 72 |  |  | $ | (37) |  |  | $ | 1,303 |  |  |  |  |  |
Natural gas revenue change: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Base rates (estimate) | $ | 1 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | 1 |  |  |  |  |  |
Effect of weather (estimate)(c) | 9 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 9 |  |  |  |  |  |
VBA | — |  |  | — |  |  | 7 |  |  | — |  |  | — |  |  | 7 |  |  |  |  |  |
Other | (1) |  |  | — |  |  | — |  |  | — |  |  | — |  |  | (1) |  |  |  |  |  |
Cost recovery mechanisms – offset in natural gas purchased for resale(e) | (3) |  |  | — |  |  | 15 |  |  | — |  |  | — |  |  | 12 |  |  |  |  |  |
Other cost recovery mechanisms(f) | — |  |  | — |  |  | 4 |  |  | — |  |  | — |  |  | 4 |  |  |  |  |  |
Total natural gas revenue change | $ | 6 |  |  | $ | — |  |  | $ | 26 |  |  | $ | — |  |  | $ | — |  |  | $ | 32 |  |  |  |  |  |

(a)Includes an increase in transmission revenues of $21 million and $60 million at Ameren Illinois for the three and nine months ended September 30, 2025, respectively, compared with the year-ago periods.
(b)For Ameren Illinois Electric Distribution and Ameren Transmission, base rates include increases or decreases in operating revenues related to the revenue requirement reconciliation adjustment under the MYRP and formula rates, respectively. For Ameren Missouri, base rates exclude an increase for the recovery of lost electric revenue, less the associated fuel and purchased power expenses, resulting from the MEEIA customer energy-efficiency programs and a decrease in base rates for RESRAM. These changes in Ameren Missouri base rates are included in the “Retail sales volumes and changes in customer usage patterns (excluding the estimated effects of weather and MEEIA)” and “Cost recovery mechanisms - offset in fuel and purchased power” line items, respectively.
(c)Represents the estimated variation resulting primarily from changes in cooling and heating degree-days on electric and natural gas demand compared with the year-ago periods; this variation is based on temperature readings from National Oceanic and Atmospheric Administration weather stations at local airports in our service territories.
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(d)Changes in RESRAM revenues are largely offset in “Fuel and purchased power,” “Other operations and maintenance,” “Depreciation and amortization,” “Taxes other than income taxes,” or “Income taxes” on the statement of income.
(e)Electric and natural gas revenue changes are offset by corresponding changes in “Fuel and purchased power” and “Natural gas purchased for resale” on the statement of income. For the three and nine months ended September 30, 2025, activity in Other/Intersegment Eliminations of $10 million and $33 million, respectively, was primarily due to the changes in Ameren Transmission revenue from transmission services provided to Ameren Illinois Electric Distribution (-$11 million and -$33 million, respectively). See Note 14 – Segment Information under Part I, Item 1, of this report for additional information on intersegment eliminations. These items have no overall impact on earnings.
(f)Offsetting expense increases or decreases are reflected in “Other operations and maintenance,” “Taxes other than income taxes,” or “Income taxes” on the statement of income. These items have no overall impact on earnings.
Electric Revenues
Ameren
Ameren’s electric revenues increased $528 million, or 26%, and $1,303 million, or 26%, for the three and nine months ended September 30, 2025, respectively, compared with the year-ago periods, primarily due to increased revenues at Ameren Missouri, Ameren Illinois Electric Distribution, and Ameren Transmission, as discussed below.
Ameren Transmission
Amer en Transmission’s electric revenues increased $30 million, or 14%, and $72 million, or 12%, for the three and nine months ended September 30, 2025, respectively, compared with the year-ago periods. Revenues were primarily affected by higher recoverable expenses
(+$12 million and +$44 million, respectively) and increased capital investment (+$8 million and +$18 million, respectively), as evidenced by a 7% increase in rate base used to calculate the revenue requirement. Additionally, revenues were favorably affected by a higher ROE
(+$10 million in both periods) due to the absence of the October 2024 FERC order that decreased base ROE for certain historical periods.
Ameren Missouri
Ameren Missouri’s electric revenues increased $361 million, or 27%, and $991 million, or 34%, for the three and nine months ended September 30, 2025, respectively, compared with the year-ago periods.
The following items increased Ameren Missouri’s electric revenues for the three and nine months ended September 30, 2025:
•“Off-system sales, capacity, transmission, and FAC revenues, net” increased $146 million and $745 million, respectively, primarily due to summer capacity prices increasing from $30 per MW-day in 2024 to $667 per MW-day in 2025 pursuant to the April 2025 annual MISO capacity auction.
•Higher electric base rates, excluding the change in base rates for the MEEIA customer energy-efficiency programs and the RESRAM, resulting from the April 2025 MoPSC electric rate order effective June 1, 2025, increased revenues an estimated $143 million and $187 million, respectively. See Note 2 – Rate and Regulatory Matters under Part I, Item 1, of this report for additional information regarding the April 2025 MoPSC electric rate order.
•The effect of weather increased revenues an estimated $37 million and $48 million, respectively, primarily due to warmer July temperatures and colder winter temperatures.
•Revenues increased $11 million and $35 million, respectively, due to surcharges related to the servicing of securitized utility tariff bonds issued in December 2024 to finance costs related to the accelerated retirement of the Rush Island Energy Center. This increase in revenue is offset by increases in interest and amortization expense. See Variable Interest Entities in Note 1 – Summary of Significant Accounting Policies under Part I, Item 1, of this report for additional information.
•Excluding the estimated effects of weather and the MEEIA customer energy-efficiency programs, electric revenues increased an estimated $23 million in both periods, primarily due to increased retail sales volumes and higher demand charges, partially offset by lower realized prices due to changes in customer usage patterns.
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The following items decreased Ameren Missouri’s electric revenues for t he three and nine months ended September 30, 2025 (except where a specific period is referenced):
•In accordance with the June 2024 MoPSC financing order, revenues decreased $26 million for the nine months ended September 30, 2025, due to the deferral of base rate revenues to a regulatory liability related to the Rush Island Energy Center since its October 15, 2024 retirement date. The deferral ended with new rates effective June 1, 2025.
•Revenues associated with “Cost recovery mechanisms – offset in fuel and purchased power” decreased $19 million for the nine months ended September 30, 2025, due to decreased revenue related to the amortization of costs previously deferred under the FAC that were reflected in customer rates. The changes to “Cost recovery mechanisms - offset in fuel and purchased power” are fully offset by changes to “Cost recovery mechanisms - offset in electric revenue” in fuel and purchased power.
•RESRAM revenues decreased $10 million and $17 million, respectively. These changes are largely offset by changes in the “Depreciation and amortization” section of the statement of income.
Ameren Illinois
Ameren Illinois’ electric revenues increased $157 million, or 23%, and $304 million, or 16%, for the three and nine months ended September 30, 2025, respectively, compared with the year-ago periods, driven by increased revenues at Ameren Illinois Electric Distribution and Ameren Illinois Transmission.
Ameren Illinois Electric Distribution
Ameren Illinois Electric Distribution’s revenues increased $147 million, or 27%, and $277 million, or 18%, for the three and nine months ended September 30, 2025, respectively, compared with the year-ago periods.
The following items increased Ameren Illinois Electric Distribution’s revenues for the three and nine months ended September 30, 2025:
•Revenues associated with “Cost recovery mechanisms – offset in fuel and purchased power” increased $126 million and $201 million, respectively, due to increased purchased power expenses recovered from customers. The increase in electric revenues are fully offset by an increase in purchased power expenses under cost recovery mechanisms for purchased power, as discussed below.
•Base rates increased revenues by $23 million and $54 million, respectively, due to higher recoverable non-purchased power expenses
(+$22 million and +$46 million, respectively) and increased capital investment (+$1 million and +$7 million, respectively).
•Other revenues increased $3 million and $12 million, respectively, primarily due to mutual assistance provided to Ameren Missouri for major storms experienced in 2025 throughout its service territory and the recovery of and return on increased customer generation rebates.
•Revenues increased $6 million and $10 million, respectively, due to the recovery of and return on increased energy-efficiency program investments under performance-based formula ratemaking.
Other cost recovery mechanisms decreased revenues by $11 million for the three months ended September 30, 2025, primarily due to a lower amount of bad debt costs included in customer rates, effective June 2025, pursuant to the associated rider.
Ameren Illinois Transmission
Ameren Illinois Transmission’s revenues increased $21 million, or 14%, and $60 million, or 14%, for the three and nine months ended September 30, 2025, respectively, compared with the year-ago periods. Base rate revenues were primarily affected by higher recoverable expe nses (+$8 million and +$39 million, respectively) and increased capital investment (+$6 million and +$14 million, respectively), as evidenced by an 8% increase in rate base used to calculate the revenue requirement. Additionally, revenues were favorably affected by a higher ROE (+$7 million in both periods) due to the absence of the October 2024 FERC order that decreased base ROE for certain historical periods.
Natural Gas Revenues
Ameren
Ameren’s natural gas revenues were comparable for the three months ended September 30, 2025, and increased $32 million, or 4%, for the nine months ended September 30, 2025, compared with the year-ago periods, due to increased revenues at Ameren Illinois Natural Gas and Ameren Missouri, as discussed below.
Ameren Missouri
Ameren Missouri’s natural gas revenues were comparable for the three months ended September 30, 2025, and increased $6 million, or 6%, for the nine months ended September 30, 2025, compared with the year-ago periods, primarily due to colder winter temperatures.
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Ameren Illinois Natural Gas
Ameren Illinois Natural Gas’ revenues were comparable for the three months ended September 30, 2025, and increased $26 million, or 4%, for the nine months ended September 30, 2025, compared with the year-ago periods. “Cost re covery mechanisms – offset in natural gas purchased for resale” increased revenues $15 million for the nine months ended September 30, 2025, due to a higher collection of natural gas costs previously deferred under the PGA. Changes in natural gas revenues under the PGA are fully offset by changes in natural gas purchased for resale expenses. Revenues increased $7 million for the nine months ended September 30, 2025 due to a change in the timing of revenues recognized under the VBA. Revenues are decoupled from actual sales volumes for residential and small nonresidential customers, and the change in the timing of revenues is not expected to materially impact full-year results.
Fuel and Purchased Power
The following table presents the increases (decreases) by Ameren segment for fuel and purchased power for the three and nine months ended September 30, 2025, compared with the year-ago periods:

Three Months | Ameren Missouri |  | Ameren Illinois Electric Distribution |  | Ameren Illinois Natural Gas |  | Ameren Transmission |  | Other /Intersegment Eliminations |  | Ameren |  |  |  |  |
Fuel and purchased power change: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Energy costs (excluding the estimated effect of weather) | $ | 148 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | 148 |  |  |  |  |  |
Retail sales volume (excluding the estimated effect of weather) | 3 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 3 |  |  |  |  |  |
Effect of weather (estimate)(a) | 4 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 4 |  |  |  |  |  |
Effect of lower net energy costs included in base rates | (3) |  |  | — |  |  | — |  |  | — |  |  | — |  |  | (3) |  |  |  |  |  |
Transmission service charges (not included in the FAC) | 2 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 2 |  |  |  |  |  |
Cost recovery mechanisms – offset in electric revenue(b) | (1) |  |  | 126 |  |  | — |  |  | — |  |  | (10) |  |  | 115 |  |  |  |  |  |
Total fuel and purchased power change | $ | 153 |  |  | $ | 126 |  |  | $ | — |  |  | $ | — |  |  | $ | (10) |  |  | $ | 269 |  |  |  |  |  |
Nine Months |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fuel and purchased power change: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Energy costs (excluding the estimated effect of weather) | $ | 750 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | 750 |  |  |  |  |  |
Retail sales volume (excluding the estimated effect of weather) | 2 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 2 |  |  |  |  |  |
Effect of weather (estimate)(a) | 8 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 8 |  |  |  |  |  |
Transmission service charges (not included in the FAC) | 7 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 7 |  |  |  |  |  |
Effect of lower net energy costs included in base rates | (3) |  |  | — |  |  | — |  |  | — |  |  | — |  |  | (3) |  |  |  |  |  |
Other | (3) |  |  | — |  |  | — |  |  | — |  |  | — |  |  | (3) |  |  |  |  |  |
Cost recovery mechanisms – offset in electric revenue(b) | (19) |  |  | 201 |  |  | — |  |  | — |  |  | (33) |  |  | 149 |  |  |  |  |  |
Total fuel and purchased power change | $ | 742 |  |  | $ | 201 |  |  | $ | — |  |  | $ | — |  |  | $ | (33) |  |  | $ | 910 |  |  |  |  |  |

(a)Represents the estimated variation resulting primarily from changes in cooling and heating degree-days on electric demand compared with the year-ago periods; this variation is based on temperature readings from the National Oceanic and Atmospheric Administration weather stations at local airports in our service territories.
(b)“Cost recovery mechanisms — offset in electric revenue” changes are offset by corresponding changes in “Cost recovery mechanisms — offset in fuel and purchased power” in electric revenues. For the three and nine months ended September 30, 2025, activity in Other/Intersegment Eliminations of $10 million and $33 million, respectively, was primarily due to the changes in Ameren Transmission revenue from transmission services provided to Ameren Illinois Electric Distribution (-$11 million and -$33 million, respectively). See Note 14 – Segment Information under Part I, Item 1, of this report for additional information on intersegment eliminations. These items have no overall impact on earnings.
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Ameren
Ameren Missouri and Ameren Illinois are generally allowed to pass on to customers prudently incurred costs for fuel and purchased power. Ameren’s electric fuel and purchased power expenses increased $269 million, or 54%, and $910 million, or 79%, for the three and nine months ended September 30, 2025, respectively, compared with the year-ago periods, primarily due to increased fuel and purchased power expenses at Ameren Missouri and Ameren Illinois Electric Distribution, as discussed below.
Ameren Missouri
Ameren Missouri’s fuel and purchased power expenses increased $153 million, or 46%, and $742 million, or 108%, for the three and nine months ended September 30, 2025, respectively, compared with the year-ago periods.
The following items increased Ameren Missouri’s fuel and purchased power expenses for the three and nine months ended September 30, 2025:
•Energy costs increased $148 million and $750 million, respectively, primarily due to summer capacity prices increasing from $30 per MW-day in 2024 to $667 per MW-day in 2025 pursuant to the April 2025 annual MISO capacity auction. Ameren Missouri’s 5% exposure to net energy cost variances under the FAC of $2 million and $5 million for the three and nine months ended September 30, 2025 is the difference between “Off-system sales, capacity, transmission, and FAC revenues, net” in electric revenues and “Energy costs (excluding the estimated effect of weather)”.
•Fuel and purchased power expenses increased an estimated $4 million and $8 million, respectively, due to an increase in electric retail sales related to weather.
•Transmission service charges (not included in the FAC) increased $2 million and $7 million, respectively, due to higher transmission rates related to increased revenue requirements of other MISO transmission operators.
“Cost recovery mechanisms — offset in electric revenue” decreased fuel and purchased power expenses $19 million for the nine months ended September 30, 2025, due to decreased amortization of costs previously deferred under the FAC. The changes to “Cost recovery mechanisms - offset in electric revenue” are fully offset by “Cost recovery mechanisms - offset in fuel and purchased power” in electric revenues.
Ameren Illinois Electric Distribution
Ameren Illinois Electric Distribution’s purchased power expenses increased $126 million, or 62%, and $201 million, or 36%, for the three and nine months ended September 30, 2025, respectively, compared with the year-ago periods, primarily due to summer capacity prices increasing from $30 per MW-day in 2024 to $667 per MW-day in 2025 pursuant to the April 2025 annual MISO capacity auction (+$47 million and +$88 million, respectively), increased volumes (+$29 million and +$51 million, respectively), primarily due to residential and small commercial customers switching from alternative retail electric suppliers to Ameren Illinois’ supplied power, increases in transmission service charges (+$11 million and +$36 million, respectively), and increased energy prices (+$33 million and +$15 million, respectively). The changes to “Cost recovery mechanisms - offset in electric revenue” are fully offset by changes to “Cost recovery mechanisms - offset in fuel and purchased power” in electric revenues.
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Natural Gas Purchased for Resale
The following table presents the increases (decreases) by Ameren segment for natural gas purchased for resale for the three and nine months ended September 30, 2025, compared with the year-ago periods:

Three Months | Ameren Missouri |  | Ameren Illinois Electric Distribution |  | Ameren Illinois Natural Gas |  | Ameren Transmission |  | Other /Intersegment Eliminations |  | Ameren |  |  |  |  |
Natural gas purchased for resale change: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cost recovery mechanisms – offset in natural gas revenue(a) | $ | 2 |  |  | $ | — |  |  | $ | (7) |  |  | $ | — |  |  | $ | — |  |  | $ | (5) |  |  |  |  |  |
Total natural gas purchased for resale change | $ | 2 |  |  | $ | — |  |  | $ | (7) |  |  | $ | — |  |  | $ | — |  |  | $ | (5) |  |  |  |  |  |
Nine Months |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Natural gas purchased for resale change: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Effect of weather (estimate)(b) | $ | 7 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | 7 |  |  |  |  |  |
Cost recovery mechanisms – offset in natural gas revenue(a) | (3) |  |  | — |  |  | 15 |  |  | — |  |  | — |  |  | 12 |  |  |  |  |  |
Total natural gas purchased for resale change | $ | 4 |  |  | $ | — |  |  | $ | 15 |  |  | $ | — |  |  | $ | — |  |  | $ | 19 |  |  |  |  |  |

(a)Natural gas purchased for resale changes are offset by corresponding changes in “Natural gas revenues” on the statement of income. These items have no overall impact on earnings.
(b)Represents the estimated variation resulting primarily from changes in cooling and heating degree-days on natural gas demand compared with the year-ago periods; this variation is based on temperature readings from the National Oceanic and Atmospheric Administration weather stations at local airports in our service territories.
Ameren
Ameren Missouri and Ameren Illinois are allowed to pass on to customers prudently incurred costs for natural gas purchased for resale. Ameren’s natural gas purchased for resale expenses were comparable for the three months ended September 30, 2025, and increased $19 million, or 9%, for the nine months ended September 30, 2025, compared with the year-ago periods, primarily due to increased natural gas purchased for resale expenses at Ameren Illinois Natural Gas, as discussed below.
Ameren Missouri
Ameren Missouri’s natural gas purchased for resale expenses were comparable for the three and nine months ended September 30, 2025, compared with the year-ago periods.
Ameren Illinois Natural Gas
Ameren Illinois Natural Gas’ natural gas purchased for resale expenses decreased $7 million, or 27%, for the three months ended September 30, 2025, and increased $15 million, or 9%, for the nine months ended September 30, 2025, compared with the year-ago periods, primarily due to the amortization of natural gas costs that were previously deferred under the PGA. Changes in natural gas purchased for resale expenses are fully offset by changes in natural gas revenues under the PGA.
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Other Operations and Maintenance Expenses

|  |  | Increase (Decrease) by Segment |
|  |  | Overall Ameren Decrease of $18 Million (QTD YoY) |  | Overall Ameren Decrease of $8 Million (YTD YoY) |
| Total by Segment(a) |  |  |

(a)Includes $19 million and $19 million at Ameren Transmission in the three months ended September 30, 2025 and 2024, respectively. Includes other/intersegment eliminations of $(3) million and $(1) million in the three months ended September 30, 2025 and 2024, respectively. Also includes other/intersegment eliminations of $(15) million and $(8) million in the nine months ended September 30, 2025 and 2024, respectively.

|  | Ameren Missouri |  |  | Ameren Illinois Natural Gas |  |  | Other/Intersegment Eliminations
|  | Ameren Illinois Electric Distribution |  | Ameren Transmission |  |  |  |

Ameren
Other operations and maintenance expenses decreased $18 million and $8 million in the three and nine months ended September 30, 2025, due to the changes discussed below. In addition to changes by segments discussed below, other operations and maintenance expenses were comparable in the three months ended September 30, 2025 and decreased $7 million in the nine months ended September 30, 2025, respectively, for activity not reported as part of a segment, as reflected in “Other/Intersegment Eliminations” above. This is primarily due to a decrease of $13 million in the elimination of the non-service cost component of net periodic benefit income in the nine months ended September 30, 2025. The non-service cost component of net periodic benefit cost or income at Ameren Services is allocated to the segments and primarily included in the segments’ other operations and maintenance expenses. The decreases are offset by the absence of a gain on the sale of land of $9 million that occurred in 2024.
Ameren Transmission
Other operations and maintenance expenses were comparable between periods.
Ameren Missouri
Other operations and maintenance expenses decreased $28 million and $41 million in the three and nine months ended September 30, 2025, respectively, compared with the year-ago periods. The following items decreased other operations and maintenance expenses in the three and nine months ended September 30, 2025, compared with the year-ago periods:
•The absence in 2025 of a $44 million and $59 million charge in the three and nine months ended September 30, 2025, related to the NSR and Clean Air Act litigation associated with the Rush Island Energy Center.
•Expenses associated with the MEEIA customer energy-efficiency program decreased $4 million and $11 million, respectively, as approved by the MoPSC in November 2024.
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The following items partially offset the decrease in other operations and maintenance expenses for the three and nine months ended September 30, 2025, compared with the year-ago periods (except where a specific period is referenced):
•Non-nuclear energy center operations and maintenance expenses increased $6 million and $10 million in the three and nine months ended September 30, 2025.
•Increased expense of $5 million and $9 million, respectively, for cloud-related software.
•Transmission and distribution storm-related expenses increased $8 million in the nine months ended September 30, 2025, primarily because of the major storms experienced throughout its service territory in 2025.
•Transmission and distribution expenditures, excluding major storm-related costs, increased $6 million and $4 million in the three and nine months ended September 30, 2025, respectively, largely due to increased vegetation management expenditures and higher levels of pole inspections.
Ameren Illinois
Other operations and maintenance expenses increased $12 million and $39 million in the three and nine months ended September 30, 2025, respectively, compared with the year-ago periods, primarily due to the following items:
Ameren Illinois Electric Distribution
Other operations and maintenance expenses increased $8 million and $41 million in the three and nine months ended September 30, 2025, respectively, primarily due to the following items (except where a specific period is referenced):
•Increased costs of $6 million and $11 million, respectively, resulting from compliance with new and expanding programs under CEJA.
•Bad debt costs on accounts receivables increased $10 million in the nine months ended September 30, 2025, primarily because of a higher base level of expenses included in customer rates pursuant to the associated rider.
•Increased costs associated with customer energy-efficiency investments under formula ratemaking of $3 million and $9 million, respectively, primarily due to amortization of regulatory assets.
•Increased expense of $4 million and $7 million, respectively, for cloud-related software.
•Distribution expenditures increased $3 million and $7 million, respectively, primarily due to higher levels of pole inspections and other maintenance activity.
•Injuries and damages increased $3 million and $5 million, respectively, primarily due to an increase in claims compared to the year-ago period.
The above increases in the three and nine months ended September 30, 2025, compared with the year-ago periods, were partially offset by the following items (except where a specific period is referenced):
•Bad debt costs on purchased receivables decreased $5 million and $11 million, respectively, primarily because of a lower base level of expenses included in customer rates pursuant to the associated rider.
•Reduction in environmental remediation rider costs of $3 million and $7 million, respectively.
•Bad debt costs on accounts receivables decreased $7 million in the three months ended September 30, 2025, primarily because of a lower base level of expenses included in customer rates, effective June 2025, pursuant to the associated rider.
Ameren Illinois Natural Gas
Other operations and maintenance expenses were comparable between periods.
Ameren Illinois Transmission
Other operations and maintenance expenses were comparable between periods.
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Depreciation and Amortization Expenses

|  |  | Increase (Decrease) by Segment |
|  |  | Overall Ameren Increase of $27 Million (QTD YoY) |  | Overall Ameren Increase of $43 Million (YTD YoY) |
| Total by Segment(a) |  |  |

(a)Includes other/intersegment eliminations of $2 million and $2 million in the three months ended September 30, 2025 and 2024, respectively. Also includes other/intersegment eliminations of $6 million and $5 million in the nine months ended September 30, 2025 and 2024, respectively.

|  | Ameren Missouri |  |  | Ameren Illinois Natural Gas |  |  | Other/Intersegment Eliminations
|  | Ameren Illinois Electric Distribution |  | Ameren Transmission |  |  |  |

Depreciation and amortization expenses increased $27 million, $19 million, and $7 million in the three months ended September 30, 2025, compared with the year-ago period at Ameren, Ameren Missouri, and Ameren Transmission, respectively, primarily because of additional property, plant, and equipment investments. Depreciation and amortization expenses increased $43 million, $25 million, and $19 million in the nine months ended September 30, 2025, compared with the year-ago period at Ameren, Ameren Transmission, and Ameren Missouri, respectively, primarily because of additional property, plant, and equipment investments. Ameren’s and Ameren Missouri’s depreciation and amortization expenses for the three and nine months ended September 30, 2025, compared with the year-ago periods, were affected by the following, which include the effect of the additional investments at Ameren Missouri:
•Increased depreciation and amortization of $16 million and $21 million, respectively, due to the inclusion in base rates of property, plant, and equipment previously eligible for deferral to a regulatory asset under the PISA and RESRAM effective June 1, 2025, pursuant to the April 2025 MoPSC electric rate order.
•The amortization of a regulatory asset associated with the securitization of Ameren Missouri’s Rush Island Energy Center increased depreciation and amortization expenses by $5 million and $16 million, respectively.
•Depreciation and amortization expenses reflected a deferral to a regulatory asset of depreciation associated with investments in eligible property, plant, and equipment not yet included in base rates, pursuant to PISA. Base rates were updated to include the eligible property, plant, and equipment in-service through December 31, 2024, when new customer rates became effective on June 1, 2025, pursuant to the April 2025 MoPSC electric rate order. The effect of rebasing PISA and increased amortization of prior PISA deferrals, increased depreciation and amortization by $10 million in both periods.
•The lower net deferral pursuant to a tracker related to certain excess deferred income taxes, which increased depreciation and amortization expenses by $7 million and $10 million, respectively.
•Depreciation and amortization rate changes effective June 1, 2025, pursuant to the April 2025 MoPSC electric rate order, which increased depreciation and amortization expenses by $4 million and $5 million, respectively.
•The absence of depreciation expense associated with Ameren Missouri’s Rush Island Energy Center decreased expenses by $9 million and $27 million, respectively.
•Lower amortization of prior deferrals and the higher net under-recovery of RESRAM eligible expenses decreased depreciation and amortization expenses by $10 million and $16 million, respectively.
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Taxes Other Than Income Taxes

|  |  | Increase (Decrease) by Segment |
|  |  | Overall Ameren Increase of $14 Million (QTD YoY) |  | Overall Ameren Increase of $23 Million (YTD YoY) |
| Total by Segment(a) |  |  |

(a)Includes $3 million, $2 million, $7 million, and $6 million at Ameren Transmission in the three months ended September 30, 2025 and 2024, and in the nine months ended September 30, 2025 and 2024, respectively. Also includes other/intersegment eliminations of $2 million, $4 million, $9 million, and $11 million in the three months ended September 30, 2025 and 2024, and in the nine months ended September 30, 2025 and 2024, respectively.

|  | Ameren Missouri |  |  | Ameren Illinois Natural Gas |  |  | Other/Intersegment Eliminations
|  | Ameren Illinois Electric Distribution |  | Ameren Transmission |  |  |  |

Taxes other than income taxes increased $14 million in the three months ended September 30, 2025, compared with the year-ago period, primarily because of an increase of $10 million in gross receipts tax at Ameren Missouri due to increased retail electric sales.
Taxes other than income taxes increased $23 million in the nine months ended September 30, 2025, compared with the year-ago period, primarily because of an increase of $13 million, $6 million, and $5 million at Ameren Missouri, Ameren Illinois Electric Distribution and Ameren Illinois Natural Gas, respectively. Taxes other than income taxes increased primarily due to an increase in gross receipts taxes of $14 million, $4 million and $4 million at Ameren Missouri, Ameren Illinois Natural Gas and Ameren Illinois Electric Distribution, respectively, resulting from increased retail natural gas and electric sales.
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Other Income, Net

|  |  | Increase (Decrease) by Segment |
|  |  | Overall Ameren Decrease of $25 Million (QTD YoY) |  | Overall Ameren Decrease of $36 Million (YTD YoY) |
| Total by Segment(a) |  |  |

(a)Includes $(3) million and $8 million at Ameren Transmission in the three months ended September 30, 2025 and 2024, respectively. Also includes $4 million and $6 million at Ameren Illinois Natural Gas in the three months ended September 30, 2025 and 2024, respectively.

|  | Ameren Missouri |  |  | Ameren Illinois Natural Gas |  |  | Other/Intersegment Eliminations
|  | Ameren Illinois Electric Distribution |  | Ameren Transmission |  |  |  |

See Note 5 – Other Income, Net, under Part I, Item 1, of this report for additional information. See Note 11 – Retirement Benefits under Part I, Item 1, of this report for more information on the non-service cost components of net periodic benefit income.
Ameren
Other income, net, decreased $25 million and $36 million in the three and nine months ended September 30, 2025, respectively, compared with the year-ago periods. In addition to changes discussed below, other income, net, decreased $3 million and $15 million, respectively, for activity not reported as part of a segment, primarily due to a decrease of $7 million and $16 million, respectively, in the non-service cost component of net periodic benefit income.
Ameren Transmission
Other income, net, decreased $11 million in the three months ended September 30, 2025 and were comparable in the nine months ended September 30, 2025, compared with the year-ago periods. This is primarily due to a $9 million impairment of an equity method investment in the three and nine months ended September 30, 2025. This decrease is offset by a $10 million increase in the allowance for equity funds used during construction, primarily resulting from a decreased level of short-term borrowings included in the calculation and higher average construction work in progress balances in the nine months ended September 30, 2025.
Ameren Missouri
Other income, net, decreased $6 million and $9 million in the three and nine months ended September 30, 2025, respectively, compared with the year-ago periods. This is primarily due to a decrease of $6 million and $8 million in the reduction in non-service cost component of net periodic benefit income in the three and nine months ended September 30, 2025, and an increase of $2 million in charitable donations related to customer assistance programs in both periods.
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Ameren Illinois
Other income, net, decreased $7 million and $4 million in the three and nine months ended September 30, 2025, respectively, compared with the year-ago periods primarily due to the decrease of $4 million and $17 million in the non-service cost component of net periodic benefit income, largely at Ameren Illinois Electric Distribution and Ameren Illinois Natural Gas. In addition, Other income, net, decreased by $4 million and $3 million due to an increase in charitable donations related to customer assistance programs in the three and nine months ended September 30, 2025, respectively, primarily at Ameren Illinois Electric Distribution. The decreases are partially offset by an $11 million increase in the allowance for equity funds used during construction in the nine months ended September 30, 2025, largely at Ameren Illinois Transmission.
Interest Charges

|  |  | Increase by Segment |
|  |  | Overall Ameren Increase of $35 Million (QTD YoY) |  | Overall Ameren Increase of $78 Million (YTD YoY) |
| Total by Segment |  |  |

|  | Ameren Missouri |  |  | Ameren Illinois Natural Gas |  |  | Other/Intersegment Eliminations
|  | Ameren Illinois Electric Distribution |  | Ameren Transmission |  |  |  |

See Note 3 – Short-term Debt and Liquidity under Part I, Item 1, of this report and the Long-term Debt and Equity section below for additional information on short-term borrowings and long-term debt, respectively, discussed below.
Ameren
Interest charges increased $35 million and $78 million in the three and nine months ended September 30, 2025, respectively, compared with the year-ago periods. In addition to changes by segments discussed below, interest charges increased $9 million and $42 million respectively, at Ameren (parent), because of increased levels of short-term borrowings that increased interest charges by $3 million and $29 million, respectively. Additionally, interest charges increased $8 million and $15 million, respectively, at Ameren (parent), due to a long-term debt issuance in March 2025 offset by the repayment of a senior unsecured note in September 2024.
Ameren Transmission
Interest charges were comparable between periods.
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Ameren Missouri
Interest charges increased $23 million and $28 million in the three and nine months ended September 30, 2025, respectively, compared with the year-ago periods. Interest charges increased by $12 million and $37 million, respectively, primarily due to the issuances of long-term debt in April 2024, October 2024, and April 2025. Interest charges also increased by $6 million and $17 million, respectively, due to the December 2024 issuance of securitized utility tariff bonds associated with the retirement of the Rush Island Energy Center, see Note 14 - Commitments and Contingencies under Part II, Item 8, in the Form 10-K for more information. Additionally, the amount of interest charges included in base rates for PISA and RESRAM was updated when new customer rates became effective on June 1, 2025, pursuant to the April 2025 MoPSC electric rate order. Lower deferrals due to the inclusion in base rates of interest associated with certain property, plant, and equipment previously deferred under the PISA and RESRAM increased interest charges by $4 million in the three months ended September 30, 2025.
The above increases were partially offset by interest charges that reflected a deferral to a regulatory asset of interest associated with investments in eligible property, plant and equipment not yet reflected in rates pursuant to PISA and RESRAM, which decreased interest charges by $22 million in the nine months ended September 30, 2025.
Ameren Illinois
Interest charges were comparable in the three months ended September 30, 2025, and increased $14 million in the nine months ended September 30, 2025, compared with the year-ago periods, primarily due to the following:
Ameren Illinois Transmission
Interest charges were comparable in the three months ended September 30, 2025, and increased by $6 million in the nine months ended September 30, 2025, compared with the year-ago periods, primarily because of issuances of long-term debt in June 2024 and March 2025, which increased interest expense by $10 million. The increases were partially offset by decreased levels of interest charges associated with short-term debt of $3 million.
Ameren Illinois Electric Distribution
Interest charges increased by $3 million and $7 million in the three and nine months ended September 30, 2025, respectively, primarily because of issuances of long-term debt in June 2024 and March 2025, which increased interest expense by $2 million and $12 million, respectively. The increases in the nine months ended September 30, 2025 were partially offset by $2 million due to decreased levels of borrowing on short-term debt and by $2 million due to the maturity of senior secured notes in March 2025.
Ameren Illinois Natural Gas
Interest charges were comparable between periods.
Income Taxes
The following table presents effective income tax rates for the three and nine months ended September 30, 2025 and 2024:

|  | Three Months(a) |  | Nine Months(a)
|  | 2025 |  | 2024 |  | 2025 |  | 2024
Ameren |  | 7 | % |  | 11 | % |  | 11 | % |  | 13 | %
Ameren Missouri |  | 6 | % |  | (2) | % |  | 6 | % |  | (1) | %
Ameren Illinois |  | 10 | % |  | 24 | % |  | 20 | % |  | 24 | %
Ameren Illinois Electric Distribution |  | 25 | % |  | 20 | % |  | 21 | % |  | 19 | %
Ameren Illinois Natural Gas |  | 25 | % |  | 22 | % |  | 26 | % |  | 27 | %
Ameren Illinois Transmission |  | 2 | % |  | 27 | % |  | 17 | % |  | 27 | %
Ameren Transmission |  | (12) | % |  | 27 | % |  | 13 | % |  | 27 | %

(a)Estimate of the annual effective income tax rate adjusted to reflect the tax effect of items discrete to the three and nine months ended September 30, 2025 and 2024.
See Note 12 – Income Taxes under Part I, Item 1, of this report for a reconciliation of the federal statutory corporate income tax rate to the effective income tax rate for the Ameren Companies.
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The effective tax rate was lower at Ameren Transmission and Ameren Illinois Transmission for the three and nine months ended September 30, 2025 compared with the year-ago periods due to a revaluation of excess deferred income tax regulatory liabilities in the third quarter of 2025. In 2024, the IRS issued a series of private letter rulings to another taxpayer, which provided guidance on applying IRS normalization rules to the calculation of tax benefits applicable to the ratemaking treatment related to net operating loss carryforwards. The rulings concluded that, for ratemaking purposes, net operating loss carryforwards should be reflected on a separate company basis and should not be reduced by payments received for the utilization of losses by other affiliates under a tax allocation agreement. In 2025, the FERC issued an order reflecting implementation of the rules for the other taxpayer who had a similar fact pattern as Ameren Illinois and ATXI. Accordingly, in the third quarter of 2025, Ameren and Ameren Illinois decreased income tax expense by $48 million and $23 million, respectively, to reflect the revaluation of excess deferred income tax regulatory liabilities resulting from TCJA for FERC-regulated jurisdictions pursuant to IRS guidance and recent FERC order.
LIQUIDITY AND CAPITAL RESOURCES
Collections from our utility tariff-based revenues are our principal source of cash provided by operating activities. A diversified retail customer mix, primarily consisting of rate-regulated residential, commercial, and industrial customers, provides us with a reasonably predictable source of cash. In addition to using cash provided by operating activities, we use available cash, drawings under committed credit agreements, commercial paper issuances, and/or, in the case of Ameren Missouri and Ameren Illinois, short-term affiliate borrowings to support normal operations and temporary capital requirements. We may reduce our short-term borrowings with cash provided by operations or, at our discretion, with long-term borrowings, or, in the case of Ameren Missouri and Ameren Illinois, with capital contributions from Ameren (parent). As of September 30, 2025, there have been no material changes other than in the ordinary course of business related to cash requirements arising from the long-term commitments for fuel for generation, purchased power, and natural gas for distribution as described under Liquidity and Capital Resources in Item 7 of the Form 10-K.
We expect to make significant capital expenditures over the next five years, supported by a combination of long-term debt and equity, as we invest in our electric and natural gas utility infrastructure to support overall system reliability, grid modernization, renewable energy target requirements, and other improvements. For additional information about our long-term debt outstanding, including maturities due within one year, and the applicable interest rates, see Note 5 – Long-term Debt and Equity Financings under Part II, Item 8 of the Form 10-K and Note 4 – Long-term Debt and Equity Financings under Part I, Item 1, of this report. As part of its funding plan for capital expenditures, Ameren is using newly-issued shares of common stock to satisfy requirements under the DRPlus and employee benefit plans and expects to continue to do so through at least 2029. Additionally, 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. There were no shares issued under the ATM program during the nine months ended September 30, 2025. As of September 30, 2025, Ameren had multiple forward sale agreements that could be settled with various counterparties relating to 12.2 million shares of common stock. Ameren expects to settle approximately $530 million of the forward sale agreements with physical delivery of 5.8 million shares of common stock by December 31, 2025 and to settle another approximately $590 million of the forward sale agreements with physical delivery of 6.4 million shares of common stock by December 31, 2026. Including issuances under the DRPlus and employee benefit plans, Ameren plans to issue approximately $600 million of equity each year from 2025 to 2029. In August 2025, Ameren increased the amount of common stock available for sale under the ATM program by $1.25 billion to a total of $3 billion. As of September 30, 2025, Ameren had approximately $1.5 billion of common stock remaining available for sale under the ATM program. The Ameren Companies expect their equity to total capitalization and cash flow metrics to support solid investment-grade credit ratings. See Long-term Debt and Equity below and Note 4 – Long-term Debt and Equity Financings under Part I, Item 1, of this report for additional information on the ATM program and forward sale agreements relating to common stock, including those under the ATM program.
The following table presents net cash provided by (used in) operating, investing, and financing activities for the nine months ended September 30, 2025 and 2024:

| Net Cash Provided By Operating Activities |  | Net Cash Used In Investing Activities |  | Net Cash Provided By Financing Activities
| 2025 |  | 2024 |  | Variance |  | 2025 |  | 2024 |  | Variance |  | 2025 |  | 2024 |  | Variance
Ameren | $ | 2,397 |  | (a) | $ | 1,946 |  | (a) | $ | 451 |  |  | $ | (3,112) |  |  | $ | (3,106) |  |  | $ | (6) |  |  | $ | 822 |  |  | $ | 1,212 |  |  | $ | (390) |
Ameren Missouri | 1,273 |  |  | 997 |  |  | 276 |  |  | (1,875) |  |  | (1,932) |  |  | 57 |  |  | 678 |  |  | 935 |  |  | (257) |
Ameren Illinois | 1,117 |  | (a) | 1,067 |  | (a) | 50 |  |  | (1,181) |  |  | (1,090) |  |  | (91) |  |  | 92 |  |  | 82 |  |  | 10 |

(a)Both Ameren and Ameren Illinois’ cash provided by operating activities included cash outflows of $85 million and $82 million for the electric energy-efficiency rider and $40 million and $20 million for the customer generation rebate program for the nine months ended September 30, 2025 and 2024, respectively.
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Cash Flows from Operating Activities
Our cash provided by operating activities is affected by fluctuations of trade accounts receivable, inventories, and accounts and wages payable, among other things, as well as the unique regulatory environment for each of our businesses. Substantially all expenditures related to fuel, purchased power, and natural gas purchased for resale are recovered from customers through rate adjustment mechanisms, which may be adjusted without a traditional regulatory rate review, subject to prudence reviews. Similar regulatory mechanisms exist for certain other operating expenses that can also affect the timing of cash provided by operating activities. The timing of cash payments for costs recoverable under our regulatory mechanisms differs from the recovery period of those costs. Additionally, the seasonality of our electric and natural gas businesses, primarily caused by seasonal customer rates and changes in customer demand due to weather, significantly affects the amount and timing of our cash provided by operating activities.
Ameren
Ameren’s cash provided by operating activities increased $451 million in the first nine months of 2025, compared with the year-ago period. The following items contributed to the increase:
•A $423 million increase resulting from higher customer collections primarily from higher electric and natural gas sales volumes due to warmer July temperatures and colder winter temperatures in 2025, increased base rates at Ameren Missouri effective June 1, 2025, pursuant to the April 2025 MoPSC electric rate order, and at Ameren Illinois, electric distribution and transmission base rate increases and higher customer collections under cost recovery mechanisms.
•A $236 million increase due to the transfer of production and investment tax credits to unrelated parties.
•A $27 million increase due to the timing of payments for spent nuclear fuel storage and reimbursements from the DOE.
The following items partially offset the increase in Ameren’s cash from operating activities between periods:
•A $120 million increase in interest payments, primarily due to higher average outstanding debt and interest rates.
•A $36 million increase in payments for the spring 2025 refueling and maintenance outage at the Callaway Energy Center. There was no outage in 2024.
•A $32 million decrease due to higher workers’ compensation claim payments and the absence of insurance proceeds received in 2024 related to workers’ compensation claims at Ameren Illinois.
•An $18 million increase in payments for coal deliveries, primarily due to increased generation at Ameren Missouri’s coal-fired energy centers in 2025.
•A $15 million increase in restoration expenses related to major storms in 2025.
•A $15 million increase in payments to contractors at Ameren Illinois, primarily related to higher levels of pole inspections and other maintenance activity and costs to comply with the CEJA.
•A $13 million increase in the cost of natural gas held in storage, primarily at Ameren Illinois, due to changes in the market price of natural gas and higher volumes.
Ameren Missouri
Ameren Missouri’s cash provided by operating activities increased $276 million in the first nine months of 2025, compared with the year-ago period. The following items contributed to the increase:
•A $236 million increase due to the transfer of production and investment tax credits to unrelated parties.
•A $138 million increase resulting from higher customer collections primarily from higher electric sales volumes due to warmer July temperatures and colder winter temperatures in 2025 and increased base rates effective June 1, 2025, pursuant to the April 2025 MoPSC electric rate order, partially offset by lower customer collections under cost recovery mechanisms.
•A $27 million increase due to the timing of payments for spent nuclear fuel storage and reimbursements from the DOE .
The following items partially offset the increase in Ameren Missouri’s cash from operating activities between periods:
•A $36 million increase in interest payments, primarily due to higher average outstanding debt and interest rates.
•A $36 million increase in payments for the spring 2025 refueling and maintenance outage at the Callaway Energy Center. There was no outage in 2024.
•An $18 million increase in payments for coal deliveries, primarily due to increased generation at coal-fired energy centers in 2025.
•A $9 million increase in restoration expenses related to major storms in 2025.
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Ameren Illinois
Ameren Illinois’ cash provided by operating activities increased $50 million in the first nine months of 2025, compared with the year-ago period, primarily due to a $278 million increase resulting from higher customer collections primarily from higher electric and natural gas distribution sales volumes due to to warmer July temperatures and colder winter temperatures in 2025, electric distribution and transmission base rate increases, and higher customer collections under cost recovery mechanisms.
The following items partially offset the increase in Ameren Illinois’ cash from operating activities between periods:
•A $121 million increase in income tax payments to Ameren (parent), pursuant to the tax allocation agreement, primarily due to higher taxable income compared to 2024.
•A $31 million decrease due to higher workers’ compensation claim payments and the absence of insurance proceeds received in 2024 related to workers’ compensation claims.
•A $30 million increase in interest payments, primarily due to higher average outstanding debt and interest rates.
•A $15 million increase in payments to contractors, primarily related to higher levels of pole inspections and other maintenance activity and costs to comply with the CEJA.
•A $13 million increase in the cost of natural gas held in storage due to changes in the market price of natural gas and higher volumes.
•A $6 million increase in restoration expenses related to major storms in 2025.
Cash Flows from Investing Activities
Ameren’s cash used in investing activities increased $6 million during the first nine months of 2025, compared with the year-ago period, primarily as a result of an $89 million increase in capital expenditures, largely resulting from increased natural gas generation-related investments at Ameren Missouri, increased expenditures for natural gas and electric distribution infrastructure upgrades at Ameren Illinois, and increased expenditures related to major storms at Ameren Missouri and Ameren Illinois. Ameren’s increase in cash used in investing activities was partially offset by a $54 million withdrawal of funds related to the cash surrender value of COLI and a $37 million decrease due to the timing of nuclear fuel expenditures at Ameren Missouri.
Ameren Missouri’s cash used in investing activities decreased $57 million during the first nine months of 2025, compared with the year-ago period, primarily as a result of a $43 million return of net money pool advances and a $37 million decrease due to the timing of nuclear fuel expenditures. Ameren Missouri’s decrease in cash used in investing activities was partially offset by a $34 million increase in capital expenditures, largely resulting from increased natural gas generation-related investments, as well as increased expenditures related to major storms.
Ameren Illinois’ cash used in investing activities increased $91 million during the first nine months of 2025, compared with the year-ago period, primarily as a result of a $51 million increase in net money pool advances, and a $36 million increase in capital expenditures, largely resulting from increased expenditures for natural gas and electric distribution infrastructure upgrades as well as increased expenditures related to major storms.
Cash Flows from Financing Activities
Cash provided by, or used in, financing activities is a result of our financing needs, which depend on the level of cash provided by operating activities, the level of cash used in investing activities, the level of dividends, and our long-term debt maturities, among other things.
Ameren’s cash provided by financing activities decreased $390 million during the first nine months of 2025, compared with the year-ago period. During the first nine months of 2025, Ameren utilized net proceeds from the issuance of long-term debt of $2.0 billion for general corporate purposes and to repay $300 million of long-term debt maturities and then-outstanding short-term debt. During the first nine months of 2025, Ameren also repaid net short-term debt of $239 million. In comparison, during the first nine months of 2024, Ameren utilized net proceeds from the issuance of long-term debt of $1.6 billion for capital expenditures, to repay then-outstanding short-term debt, and to repay $49 million of maturities of long-term debt at ATXI. In addition, during the first nine months of 2024, Ameren utilized proceeds from net commercial paper issuances of $1.0 billion along with cash on hand and cash provided by operating activities to repay $800 million of long-term debt maturities at Ameren (parent) and Ameren Missouri, and to fund, in part, capital expenditures. During the first nine months of 2025, Ameren paid common stock dividends of $576 million, compared with $535 million in the year-ago period, as a result of an increase in both the dividend rate and the number of common shares outstanding.
Ameren Missouri’s cash provided by financing activities decreased $257 million during the first nine months of 2025, compared with the year-ago period. During the first nine months of 2025, Ameren Missouri utilized net proceeds from the issuance of long-term debt of $500 million to repay then-outstanding short-term debt. In addition, during the first nine months of 2025, Ameren Missouri utilized proceeds from net commercial paper issuances of $259 million, money pool borrowings of $51 million, and cash provided by operating activities to fund, in part, capital expenditures. In comparison, during the first nine months of 2024, Ameren Missouri utilized net proceeds from the issuance of
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long-term debt of $846 million for capital expenditures and to repay then-outstanding short-term debt. Additionally, during the first nine months of 2024, Ameren Missouri utilized net commercial paper issuances totaling $406 million, capital contributions from Ameren (parent) of $350 million, and cash provided by operating activities to fund, in part, capital expenditures. Ameren Missouri also repaid $350 million of long-term debt maturities and $289 million of money pool borrowings during the first nine months of 2024. During the first nine months of 2025, Ameren Missouri also paid common stock dividends of $125 million.
Ameren Illinois’ cash provided by financing activities increased $10 million during the first nine months of 2025, compared with the year-ago period. During the first nine months of 2025, Ameren Illinois utilized proceeds from the issuance of long-term debt of $711 million to repay $300 million of long-term debt maturities and then-outstanding short-term debt. Ameren Illinois also repaid net commercial paper borrowings of $88 million and money pool borrowings of $37 million during the first nine months of 2025. In comparison, during the first nine months of 2024, Ameren Illinois utilized proceeds from the issuance of long-term debt of $624 million to repay then-outstanding short-term debt. In addition, during the first nine months of 2024, Ameren Illinois repaid net commercial paper borrowings of $349 million and money pool borrowings of $135 million. During the first nine months of 2025, Ameren Illinois also paid common stock dividends of $185 million compared with $50 million in the year-ago period.
See Long-term Debt and Equity in this section for additional information on maturities and issuances of long-term debt, and issuances of common stock.
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Short-term Debt and Liquidity
The following table presents Ameren’s consolidated net available liquidity as of September 30, 2025:

|  |  |  |  | Available at September 30, 2025
Ameren (parent) and Ameren Missouri: |  |  |  |  |
Missouri Credit Agreement – borrowing capacity |  |  |  |  | $ | 1,400 |
Less: Ameren (parent) commercial paper outstanding |  |  |  |  | 379 |
Less: Ameren Missouri commercial paper outstanding |  |  |  |  | 259 |
Less: Letters of credit |  |  |  |  | 55 |
Missouri Credit Agreement – subtotal |  |  |  |  | 707 |
Ameren (parent) and Ameren Illinois: |  |  |  |  |
Illinois Credit Agreement – borrowing capacity |  |  |  |  | 1,200 |
Less: Ameren (parent) commercial paper outstanding |  |  |  |  | 265 |
Less: Letters of credit |  |  |  |  | 4 |
Illinois Credit Agreement – subtotal |  |  |  |  | 931 |
Subtotal |  |  |  |  | $ | 1,638 |
Add: Cash and cash equivalents |  |  |  |  | 9 |
Net Available Liquidity(a) |  |  |  |  | $ | 1,647 |

(a)Does not include Ameren’s forward equity sale agreements. See Note 4 – Long-term Debt and Equity Financings under Part I, Item 1, of this report for additional information.
The Credit Agreements, among other things, provide $2.6 billion of credit until maturity in December 2028. See Note 3 – Short-term Debt and Liquidity under Part I, Item 1, of this report for additional information on the Credit Agreements. During the nine months ended September 30, 2025, Ameren (parent), Ameren Missouri, and Ameren Illinois each issued commercial paper. Borrowings under the Credit Agreements and commercial paper issuances are based upon available interest rates at the time of the borrowing or issuance.
Ameren has a money pool agreement with and among its utility subsidiaries to coordinate and to provide for certain short-term cash and working capital requirements. As short-term capital needs arise, and based on availability of funding sources, Ameren Missouri and Ameren Illinois will access funds from the utility money pool, the Credit Agreements, or the commercial paper programs depending on which option has the lowest interest rates.
See Note 3 – Short-term Debt and Liquidity under Part I, Item 1, of this report for additional information on credit agreements, commercial paper issuances, Ameren’s money pool agreements and related borrowings, and relevant interest rates.
The issuance of short-term debt securities by Ameren’s utility subsidiaries is subject to FERC approval under the Federal Power Act. In January 2025, the FERC issued orders authorizing Ameren Missouri, Ameren Illinois, and ATXI to issue up to $1.4 billion, $1 billion, and $500 million, respectively, of short-term debt securities through January 2027.
The Ameren Companies continually evaluate the adequacy and appropriateness of their liquidity arrangements for changing business conditions. When business conditions warrant, changes may be made to the existing Credit Agreements or to other borrowing arrangements, or other arrangements may be made.
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Long-term Debt and Equity
The following table presents issuances (net of any issuance premiums or discounts) of long-term debt and equity, as well as redemptions and maturities of long-term debt for the nine months ended September 30, 2025 and 2024:

| Month Issued, Redeemed, or Matured |  | 2025 |  | 2024 |
Issuances of Long-term Debt |  |  |  |  |  |
Ameren: |  |  |  |  |  |
5.375% Senior unsecured notes due 2035 | March |  | $ | 749 |  |  | $ | — |  |
Ameren Missouri: |  |  |  |  |  |
5.25% First mortgage bonds due 2054 | January |  | — |  |  | 347 |  |
5.25% First mortgage bonds due 2035 | April |  | 500 |  |  | — |  |
5.20% First mortgage bonds due 2034 | April |  | — |  |  | 499 |  |
Ameren Illinois: |  |  |  |  |  |
5.625% First mortgage bonds due 2055 | March |  | 350 |  |  | — |  |
5.55% First mortgage bonds due 2054 | June |  | — |  |  | 624 |  |
5.625% First mortgage bonds due 2055 | September |  | 361 |  |  | — |  |
ATXI: |  |  |  |  |  |
5.17% Senior unsecured notes due 2039 | August |  | — |  |  | 70 |  |
5.42% Senior unsecured notes due 2053 | August |  | — |  |  | 70 |  |
Total Ameren long-term debt issuances |  |  | $ | 1,960 |  |  | $ | 1,610 |  |
Issuances of Common Stock |  |  |  |  |  |
Ameren: |  |  |  |  |  |
DRPlus and 401(k)(a)(b) | Various |  | $ | 35 |  |  | $ | 30 |  |
Total Ameren common stock issuances(c) |  |  | $ | 35 |  |  | $ | 30 |  |
Maturities of Long-term Debt |  |  |  |  |  |
Ameren: |  |  |  |  |  |
2.50% Senior unsecured notes due 2024 | September |  | $ | — |  |  | $ | 450 |  |
Ameren Missouri: |  |  |  |  |  |
3.50% Senior secured notes due 2024 | April |  | — |  |  | 350 |  |
Ameren Illinois: |  |  |  |  |  |
3.25% Senior secured notes due 2025 | March |  | 300 |  |  | — |  |
ATXI: |  |  |  |  |  |
3.43% Senior unsecured notes due 2050 | August |  | — |  |  | 49 |  |
Total Ameren long-term debt maturities |  |  | $ | 300 |  | (d) | $ | 849 |  |

(a)Ameren issued a total of 0.3 million and 0.4 million shares of common stock under its DRPlus and 401(k) plan for the nine months ended September 30, 2025 and 2024, respectively.
(b)Excludes a $7 million and $7 million receivable at September 30, 2025 and 2024, respectively.
(c)Excludes 0.3 million and 0.2 million shares of common stock valued at $25 million and $16 million issued for no cash consideration in connection with stock-based compensation for the nine months ended September 30, 2025 and 2024, respectively.
(d)Excludes Ameren (parent)’s June 2025 purchase of senior secured notes and first mortgage bonds issued by Ameren Missouri and first mortgage bonds issued by Ameren Illinois for $24 million in aggregate.
See Note 4 – Long-term Debt and Equity Financings under Part I, Item 1, of this report for additional information, including proceeds from issuances of long-term debt, the use of those proceeds, Ameren’s forward equity sale agreements, and the ATM program.
Indebtedness Provisions and Other Covenants
At September 30, 2025, the Ameren Companies were in compliance with the provisions and covenants contained in their credit agreements, indentures, and articles of incorporation, as applicable, and ATXI was in compliance with the provisions and covenants contained in its note purchase agreements. See Note 3 – Short-term Debt and Liquidity under Part I, Item 1, of this report and Note 4 – Short-term Debt and Liquidity and Note 5 – Long-term Debt and Equity Financings under Part II, Item 8, of the Form 10-K for a discussion of provisions, applicable cross-default provisions, and covenants contained in our credit agreements, in ATXI’s note purchase agreements, and in certain of the Ameren Companies’ indentures and articles of incorporation.
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We consider access to short-term and long-term capital and credit markets to be a significant source of funding for capital requirements not satisfied by cash provided by our operating activities. Inability to raise capital on reasonable terms, particularly during times of uncertainty in the capital and credit markets, could negatively affect our ability to maintain and expand our businesses. After assessing their respective current operating performance, liquidity, and credit ratings (see Credit Ratings below), Ameren, Ameren Missouri, and Ameren Illinois each believes that it will continue to have access to the capital and credit markets on reasonable terms. However, events beyond Ameren’s, Ameren Missouri’s, and Ameren Illinois’ control may create uncertainty in the capital and credit markets or make access to the capital and credit markets uncertain or limited. Such events could increase our cost of capital and adversely affect our ability to access the capital and credit markets.
Dividends
The amount and timing of dividends payable on Ameren’s common stock are within the sole discretion of Ameren’s board of directors. Ameren’s board of directors has not set specific targets or payout parameters when declaring common stock dividends, but it considers various factors, including Ameren’s overall payout ratio, payout ratios of our peers, projected cash flow and potential future cash flow requirements, historical earnings and cash flow, projected earnings, impacts of regulatory orders or legislation, and other key business considerations. Ameren expects its dividend payout ratio to be between 55% and 65% of annual earnings over the next few years.
See Note 4 – Short-term Debt and Liquidity and Note 5 – Long-term Debt and Equity Financings under Part II, Item 8, of the Form 10-K for additional discussion of covenants and provisions contained in certain of the Ameren Companies’ financial agreements and articles of incorporation that would restrict the Ameren Companies’ payment of dividends in certain circumstances. At September 30, 2025, none of these circumstances existed at Ameren, Ameren Missouri, or Ameren Illinois and, as a result, these companies were not restricted from paying dividends.
The following table presents common stock dividends declared and paid by Ameren Corporation to its common shareholders and by Ameren subsidiaries to their parent, Ameren Corporation, for the nine months ended September 30, 2025 and 2024:

| Nine Months
| 2025 |  | 2024
Ameren | $ | 576 |  |  | $ | 535 |
Ameren Missouri | 125 |  |  | — |
Ameren Illinois | 185 |  |  | 50 |
ATXI | 49 |  |  | — |

Credit Ratings
Our credit ratings affect our liquidity, our access to the capital and credit markets, our cost of borrowing under our credit facilities and our commercial paper programs, and our collateral posting requirements under commodity contracts.
The following table presents the principal credit ratings by Moody’s and S&P, as applicable, effective on the date of this report:

|  | Moody’s |  | S&P
Ameren: |  |  |  |
Issuer/corporate credit rating |  | Baa1 |  | BBB+
Senior unsecured debt |  | Baa1 |  | BBB
Commercial paper |  | P-2 |  | A-2
Ameren Missouri: |  |  |  |
Issuer/corporate credit rating |  | Baa1 |  | BBB+
Secured debt |  | A2 |  | A
Senior unsecured debt |  | Baa1 |  | Not Rated
Commercial paper |  | P-2 |  | A-2
AMF securitized utility tariff bonds |  | Aaa |  | AAA
Ameren Illinois: |  |  |  |
Issuer/corporate credit rating |  | A3 |  | BBB+
Secured debt |  | A1 |  | A
Senior unsecured debt |  | A3 |  | BBB+
Commercial paper |  | P-2 |  | A-2
ATXI: |  |  |  |
Issuer credit rating |  | A2 |  | Not Rated
Senior unsecured debt |  | A2 |  | Not Rated

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A credit rating is not a recommendation to buy, sell, or hold securities. It should be evaluated independently of any other rating. Ratings are subject to revision or withdrawal at any time by the rating organization.
Collateral Postings
Any weakening of our credit ratings may reduce access to capital and trigger additional collateral postings and prepayments. Such changes may also increase the cost of borrowing, resulting in an adverse effect on earnings. Cash collateral postings and prepayments made with external parties were immaterial and cash collateral posted by external parties were $58 million for Ameren and Ameren Illinois at September 30, 2025. A sub-investment-grade issuer or senior unsecured debt rating (below “Baa3” from Moody’s or below “BBB-” from S&P) at September 30, 2025, could have resulted in Ameren, Ameren Missouri, or Ameren Illinois being required to post additional collateral or other assurances for certain trade and contractual obligations amounting to $701 million, $657 million, and $44 million, respectively.
Changes in commodity prices could trigger additional collateral postings and prepayments. Based on credit ratings at September 30, 2025, if market prices were 15% higher or lower than September 30, 2025 levels in the next 12 months and 20% higher or lower thereafter through the end of the term of the commodity contracts, then Ameren, Ameren Missouri, and Ameren Illinois could be required to post an immaterial amount, compared to each company’s liquidity, of collateral or provide other assurances for certain trade and contractual obligations.
OUTLOOK
Below are some key trends, events, and uncertainties that may reasonably affect our results of operations, financial condition, or liquidity, as well as our ability to achieve strategic and financial objectives, for 2025 and beyond. For additional information regarding recent rate orders, lawsuits, and pending requests filed with state and federal regulatory commissions, including those discussed below, see Note 2 – Rate and Regulatory Matters under Part I, Item 1, of this report and Note 2 – Rate and Regulatory Matters under Part II, Item 8, of the Form 10-K.
Operations
•In April 2025, Missouri Senate Bill 4 was enacted and became effective in August 2025. The law made modifications to integrated resource planning, which requires Missouri electric utilities to file plans for meeting their customers' long-term energy needs. By August 2027, the MoPSC will publish a schedule for Missouri electric utilities to file integrated resource plans every four years. The MoPSC will be required to issue an order on the plans and shall determine whether the electric utility has submitted sufficient documentation and selected preferred resource plans representing a reasonable and prudent means of serving the utility's load obligations at just and reasonable rates. In making this determination, the MoPSC shall consider whether the plans appropriately balance specific factors described in the law. If the MoPSC approves the plans, requests for CCNs for new generation facilities to be constructed or acquired as a part of the approved plans shall be deemed necessary and convenient and the scope of the CCN proceedings to review projects will be limited. The approved generation facilities will also be eligible to include construction work in progress in rate base, subject to MoPSC approval, which would improve the timeliness of cash recovery. Utilities are not allowed to capitalize allowance for funds used during construction on amounts included in rate base under this provision. The amount of construction work in progress to be included in rate base is limited to prudently incurred expenditures made within the construction period for the facility. Separately, outside of the integrated resource planning process discussed above, the law allows a Missouri electric utility to request that the MoPSC authorize the inclusion of construction work in progress for new natural gas-fired generation facilities in rate base, subject to the same restrictions discussed above. The provisions allowing for the inclusion of construction work in progress on natural gas-fired generation in rate base expire in December 2035, unless Ameren Missouri requests and receives MoPSC approval of an extension through 2045. Also, beginning in July 2026 the law allows natural gas utilities to file regulatory rate reviews using a future test year, subject to MoPSC approval. If a natural gas utility is allowed to use a future test year, a reconciliation of the actual rate base and certain forecasted costs will be performed 45 days after the end of the test year. If a given year’s actual revenue requirement is less than the revenue requirement approved by the MoPSC due to changes in rate base or certain other costs, an adjustment is made to reduce natural gas operating revenues with an offset to a regulatory liability to reflect that test year’s amounts. The regulatory liability will then be refunded to customers in the next regulatory rate review and will accrue carrying costs at the applicable WACC. The law also requires an electric utility to develop and submit to the MoPSC schedules that include its service tariff applicable to customers projected to have 100 MWs or more of demand. These schedules must reasonably ensure that such high-demand customers’ rates reflect a representative share of the costs incurred to serve them and further, must prevent other lower-demand customer rates from reflecting any unjust or unreasonable costs arising from service provided to these high-demand customers. The law also made certain modifications to the PISA as discussed below.
•The PISA permits Ameren Missouri to defer and recover 85% of the depreciation expense for investments in qualifying property, plant, and equipment placed in service and not included in base rates. Investments not eligible for recovery under the PISA include amounts related to new nuclear generation facilities and service to new customer premises. Additionally, the PISA permits Ameren Missouri to earn a return at the applicable WACC on 85% of rate base that incorporates those qualifying investments, as well as changes in total
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accumulated depreciation excluding retirements and plant-related deferred income taxes since the previous regulatory rate review. The regulatory asset for accumulated PISA deferrals also earns a return at the applicable WACC until added to rate base prospectively. Ameren Missouri recognizes an offset to “Interest Charges” on its consolidated statement of income for its carrying cost of debt relating to each return allowed under the PISA, with the difference between the applicable WACC and its carrying cost of debt recognized in revenues when recovery of PISA deferrals is reflected in customer rates. Approved PISA deferrals are recovered over a period of 20 years following a regulatory rate review. Additionally, under the RESRAM, Ameren Missouri is permitted to recover the 15% of depreciation expense not recovered under the PISA, and earn a return at the applicable WACC for investments in renewable generation plant placed in service to comply with Missouri’s renewable energy standard. Accumulated RESRAM deferrals earn carrying costs at short-term interest rates. The PISA and the RESRAM mitigate the effects of regulatory lag between regulatory rate reviews. Those investments not eligible for recovery under the PISA and the remaining 15% of certain property, plant, and equipment placed in service, unless eligible for recovery under the RESRAM, remain subject to regulatory lag. As a result of the PISA election, additional provisions of the law apply to Ameren Missouri, including limitations on electric customer rate increases. Pursuant to Missouri law enacted in April 2025 and discussed above, Ameren Missouri’s PISA election was extended through 2035 and an additional extension through 2040 is allowed if requested by Ameren Missouri and approved by the MoPSC. This law also reduced the annual limit on increases to the electric service revenue requirement used to set customer rates, compared to the revenue requirement established in the immediately preceding rate order, due to the inclusion of incremental PISA deferrals in the revenue requirement. The annual limit in effect was 2.5% and changed to 2.25%, prorated monthly, for revenue requirements approved by the MoPSC after August 2025.
•In April 2025, the MoPSC issued an order that authorizes an increase of $355 million to Ameren Missouri’s annual revenue requirement for electric retail service, effective June 1, 2025. The order 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. As a result of this order, Ameren Missouri expects a year-over-year increase to 2025 earnings, compared to 2024, of approximately $120 million and a year-over-year increase to 2026 earnings, compared to 2025, of approximately $30 million.
•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 authorizes an increase of $32 million to Ameren Missouri’s annual revenue requirement for natural gas delivery service, effective September 1, 2025.
•In November 2025, Ameren Missouri updated its May 2025 request with the MoPSC 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. A decision by the MoPSC is expected by February 2026.
•Ameren Illinois and ATXI use a forward-looking rate calculation with an annual revenue requirement reconciliation for each company’s electric transmission business. Based on expected rate base and the currently allowed 10.48% ROE, which includes a 50-basis-point incentive adder for participation in an RTO, the revenue requirements that will be included in 2026 rates for Ameren Illinois’ and ATXI’s electric transmission businesses are $685 million and $265 million, respectively. These revenue requirements represent increases in Ameren Illinois’ and ATXI’s revenue requirements of $42 million and $33 million, respectively, from the revenue requirements reflected in 2025 rates, primarily due to higher expected rate base. These rates will affect Ameren Illinois’ and ATXI’s cash receipts during 2026, but will not determine their respective electric transmission service operating revenues, which will instead be based on 2026 actual recoverable costs, rate base, and a return on rate base at the applicable WACC as calculated under the FERC formula ratemaking framework.
•In 2020, the FERC issued a Notice of Proposed Rulemaking on its transmission incentives policy, which proposed to increase the incentive ROE for participation in an RTO to 100 basis points from the current 50 basis points and revised the parameters for awarding incentives, while limiting the overall incentives to a cap of 250 basis points, among other things. In 2021, the FERC issued a Supplemental Notice of Proposed Rulemaking, which proposed to modify the Notice of Proposed Rulemaking’s incentive for participation in an RTO by limiting this incentive for utilities that join an RTO to 50 basis points and only allowing them to earn the incentive for three years, among other things. If this proposal is included in a final rule, Ameren Illinois and ATXI would no longer be eligible for the 50 basis point RTO incentive adder, prospectively. The FERC is under no deadline to issue a final rule on this matter. Ameren is unable to predict the ultimate impact of any changes to the FERC’s incentives policy. A 50-basis-point change in the FERC-allowed ROE would affect Ameren’s and Ameren Illinois’ annual net income by an estimated $17 million and $12 million, respectively, based on each company’s 2025 projected rate base.
•Pursuant to the CEJA, Ameren Illinois may file an MYRP with the ICC to establish base rates for electric distribution service to be
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charged to customers for each calendar year of a four-year period. The base rates for a particular calendar year are based on forecasted recoverable costs and an ICC-determined ROE applied to Ameren Illinois’ forecasted average annual rate base using a forecasted capital structure, with a common equity ratio of up to 50% being deemed prudent and reasonable by law and a higher equity ratio requiring specific ICC approval. The ROE determined by the ICC for each calendar year of the four-year period is subject to annual adjustments based on certain performance incentives and penalties. An MYRP allows Ameren Illinois to reconcile electric distribution service rates to its actual revenue requirement on an annual basis, subject to a reconciliation cap and adjustments to the ROE. Under the MYRP discussed below, Ameren Illinois’ 2025 electric distribution service revenues will be based on its 2025 actual recoverable costs, 2025 year-end rate base, and an ROE of 8.72%, as adjusted for any performance incentives or penalties, provided the actual revenue requirement does not exceed the reconciliation cap. If a given year’s revenue amount collected from customers varies from the approved revenue requirement, an adjustment is made to electric operating revenues with an offset to a regulatory asset or liability to reflect that year’s actual revenue requirement. The regulatory balance is then collected from, or refunded to, customers within two years from the end of the applicable annual period. Additionally, the RBA ensures electric distribution service revenues are decoupled from sales volumes and wholesale and miscellaneous revenue differences from those assumed in the revenue requirement approved by the ICC. The RBA remains effective whether Ameren Illinois elects to file an MYRP or a traditional regulatory rate review. In April 2025, Ameren Illinois filed for a reconciliation adjustment to its 2024 electric distribution service revenue requirement with the ICC. In September 2025, Ameren Illinois filed a revised reconciliation adjustment, requesting recovery of $60 million. An ICC decision in this proceeding is required by December 2025, and any approved adjustment would be collected from customers in 2026.
•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. Using the 2023 revenue requirement as a starting point, the approved revenue requirements in the ICC’s December 2024 order represent a cumulative four-year increase of $308 million. 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. The appellate court is under no deadline to address the appeal, and Ameren Illinois cannot predict the ultimate outcome of the appeal.
•Pursuant to Illinois law, Ameren Illinois’ electric energy-efficiency investments are deferred as a regulatory asset and earn a return at the applicable WACC, with the ROE component based on the annual average of the monthly yields of the 30-year United States Treasury bonds plus 580 basis points. The allowed ROE on electric energy-efficiency investments can be increased or decreased by up to 200 basis points, depending on the achievement of annual energy savings goals. The ICC has approved a plan for Ameren Illinois to invest approximately $126 million in electric energy-efficiency programs 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 2025, Ameren Illinois filed a request with the ICC seeking approval to increase its annual revenues for natural gas delivery service. In July 2025, Ameren Illinois filed a revised request seeking to increase its annual revenues by $135 million. A decision by the ICC in this proceeding is required by early December 2025, with new rates expected to be effective in early December 2025. Ameren Illinois cannot predict the level of any delivery service rate change the ICC may approve, nor whether any rate change that may eventually be approved will be sufficient to enable Ameren Illinois to recover its costs and to earn a reasonable return on investments when the rate changes go into effect.
•A November 2023 ICC order directed the ICC staff to develop a plan for a future of gas proceeding. All of the Illinois natural gas utilities subject to ICC regulation are included in this proceeding, which is exploring issues involving the decarbonization of the natural gas distribution system in light of the state of Illinois’ goal of economy-wide 100% clean energy by 2050, pursuant to the CEJA. Some of the issues being addressed include the mitigation of any natural gas distribution stranded assets, the role of energy efficiency in decarbonization, and the associated impacts of natural gas decarbonization to the electric distribution system, among others. A final ICC staff report is expected in early 2026 and will be used by the ICC to guide further action, if any.
•Ameren Missouri’s next refueling and maintenance outage at the Callaway Energy Center is scheduled for the fall of 2026. During a scheduled refueling, which occurs every 18 months, maintenance expenses are deferred as a regulatory asset and amortized until the completion of the next refueling and maintenance outage. During an outage, depending on the availability of its other generation sources and the market prices for power, Ameren Missouri’s purchased power costs may increase and the amount of excess power available for sale may decrease versus non-outage years. Changes in purchased power costs and excess power available for sale are included in the FAC, which results in limited impacts to earnings. In addition, Ameren Missouri may incur increased non-nuclear energy center maintenance costs in non-outage years.
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•In late 2024 three turbines at the High Prairie Energy Center collapsed, resulting in significantly reduced operation of the energy center. While the investigation into the cause of the collapse is ongoing, a large majority of the turbines at the energy center have returned to operation, and work is ongoing to restore the remaining turbines.
•In April 2025, the MISO released the results of its annual capacity auction, which included a fall capacity price decrease in certain portions of the central region of the MISO footprint, where Ameren Missouri’s service territory is located. Fall capacity prices decreased from $720 per MW-day in 2024 to $92 per MW-day in 2025. Based on the capacity prices set by the April 2025 MISO auction, Ameren Missouri estimates decreases to capacity revenues and purchased power costs in the fourth quarter of 2025, compared to the fourth quarter of 2024, of approximately $290 million. Ameren Missouri sells nearly all of its capacity to the MISO and purchases the capacity it needs to supply its native load sales from the MISO. Ameren Missouri’s capacity revenues and purchased power costs are a part of the net energy costs recoverable under the FAC, with 95% of the variance between net energy costs and the amount set in base rates recovered or refunded through the FAC.
•Ameren Missouri and Ameren Illinois continue to make infrastructure investments and expect to seek increases to electric and natural gas rates to recover the cost of investments and earn an adequate return. Ameren Missouri and Ameren Illinois will also seek new, or to maintain existing, regulatory and legislative solutions to address regulatory lag and to support investment in their utility infrastructure for the benefit of their customers. Ameren Missouri and Ameren Illinois continue to face cost recovery pressures, higher cost of debt, customer conservation efforts, the impacts of additional customer energy-efficiency programs, and increased customer use of increasingly cost-effective advancements in innovative energy technologies, including private generation and battery storage. We expect a net increase in demand resulting from the electrification of the economy, including in the transportation sector. In addition, several entities in various industries, including data center, manufacturing, aviation and defense, and biotechnology, are considering either locating or expanding their operations within our service territories. As a result, Ameren Missouri filed a request to modify its existing large primary service tariff as discussed above. Construction agreements associated with new data centers representing a maximum of approximately 3 gigawatts have been signed, subject to MoPSC approval of the modified large primary service tariff. Serving these new loads will require increased investments, including future investments for system reliability improvements and new generation sources, that will result in rate base growth.
Liquidity and Capital Resources
•In 2025, the presidential administration took executive action to impose additional foreign trade tariffs on various goods imported from numerous countries, and several of these countries imposed retaliatory foreign trade tariffs in response. Some of these foreign trade tariffs have been modified several times and/or paused for specific periods of time. The Ameren Companies are assessing the foreign trade tariffs and have not experienced material impacts on their results of operations, financial position, and liquidity, but the foreign trade tariffs may have future impacts. The Ameren Companies will continue to take actions to mitigate risks associated with costs and project timelines.
•As discussed above, several entities in various industries, including data center and manufacturing, are considering either locating or expanding their operations within Ameren Missouri’s service territory. In order to address these load growth opportunities and ensure reliability, Ameren Missouri filed a notice of change in its preferred resource plan with the MoPSC in February 2025. Ameren is continuing to target net-zero carbon emissions by 2045, as well as a 60% reduction by 2030 and an 85% reduction by 2040 based on 2005 levels in a safe, reliable, and affordable manner. Ameren’s goals include both reduction of direct emissions from operations (scope 1), as well as electricity usage at Ameren buildings (scope 2), including other greenhouse gas emissions of methane, nitrous oxide, and sulfur hexafluoride. Achieving these goals will be dependent on a variety of factors, including cost-effective advancements in innovative energy technologies and constructive federal and state energy and economic policies. The 2025 Change to the 2023 PRP includes, among other things, the following:
•estimated total load growth of 1.5 gigawatts by 2032 and 2.5 gigawatts by 2040;
•adding 1,600 MWs of natural gas-fired simple-cycle generation by 2030, which will be achieved through the 1,600 MWs of natural gas generation projects discussed in Note 2 – Rate and Regulatory Matters under Part I, Item 1, of this report, and an additional 1,200 MWs by 2043;
•adding 2,100 MWs of natural gas-fired combined-cycle generation by 2035 and an additional 1,200 MWs by 2040;
•adding 3,200 MWs of renewable generation by 2030, which includes the 650 MWs of solar generation projects discussed in Note 2 – Rate and Regulatory Matters under Part I, Item 1, of this report, and an additional 1,500 MWs by 2035;
•adding 1,000 MWs of battery storage by 2030, which includes the 400-MW Big Hollow Battery Energy Storage Project discussed in Note 2 – Rate and Regulatory Matters under Part I, Item 1, of this report, and an additional 800 MWs by 2042;
•adding 1,500 MWs of nuclear generation by 2040;
•retiring all of Ameren Missouri’s coal-fired energy centers by 2042;
•retiring 1,800 MWs of Ameren Missouri’s natural gas-fired energy centers by 2040 to comply with Illinois law;
•the continued implementation of customer energy-efficiency and demand response programs; and
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•the expectation that Ameren Missouri will seek and receive NRC approval for an extension of the operating license for the Callaway Energy Center beyond its current 2044 expiration date.
Ameren Missouri’s plan could be affected by, among other factors: Ameren Missouri’s ability to obtain CCNs from the MoPSC, and any other required state or federal approvals for the addition of renewable resources, battery storage, or nuclear or natural gas-fired generation, retirement of energy centers, and new or continued customer energy-efficiency programs; the ability to enter into agreements for renewable, natural gas-fired, or nuclear generation and acquire or construct that generation at a reasonable cost; the ability of suppliers, contractors, and developers to meet contractual commitments and complete projects timely, which is dependent upon the availability of necessary labor, materials, and equipment, geopolitical conflict, or government actions, among other things; changes in the scope and timing of projects; the continued existence and ability to qualify for, and use or transfer, federal production or investment tax credits; the ability to maintain system reliability during and after the transition to clean energy generation; new and/or changes in environmental regulations, including those related to CO 2 and other greenhouse gas emissions; energy prices; and demand; Ameren Missouri’s ability to obtain necessary rights-of-way, easements, and transmission interconnection agreements at an acceptable cost and in a timely fashion; the ability to earn an adequate return on invested capital; and the ability to raise capital on reasonable terms. The next preferred resource plan is required to be filed by October 2026.
•Through 2029, we expect to make significant capital expenditures to improve our electric and natural gas utility infrastructure, with a major portion directed to our transmission and distribution systems. We estimate that we will invest up to $27.4 billion (Ameren Missouri – up to $17.5 billion; Ameren Illinois – up to $7.0 billion; ATXI – up to $2.9 billion) of capital expenditures during the period from 2025 through 2029. These estimates include the MISO long-range transmission projects assigned to Ameren, as well as the first tranche competitive projects awarded to ATXI discussed below.
•In 2021, the MISO issued a report outlining a preliminary long-range transmission planning roadmap of projects through 2039, which considers the rapidly changing generation mix within MISO resulting from significant additions of renewable generation, actual and expected generation plant closures, and state mandates or goals for clean energy or carbon emissions reductions. In 2022, the MISO approved the first tranche of projects under the roadmap. A portion of these projects were assigned to various utilities, of which Ameren was awarded projects that are estimated to cost approximately $1.8 billion, based on the MISO’s cost estimate. Related to these projects, Ameren began substation upgrades in May 2024 in advance of transmission line construction, which is expected to begin in 2026, with forecasted completion dates near the end of this decade. In addition, the MISO awarded three competitive bid projects to ATXI that represent a total estimated investment of approximately $220 million for ATXI. In July 2025, the ICC issued an order approving a request filed by Ameren Illinois and ATXI for a CCN, among other things, related to the portion of the MISO long-range transmission projects they will construct within the ICC’s jurisdiction. In 2024, ATXI filed requests for CCNs, among other things, with the MoPSC related to the MISO long-range transmission projects that it expects to construct within the MoPSC’s jurisdiction. In July 2025, the MoPSC issued an order approving a CCN for a portion of the projects and a decision on the remaining projects is expected in 2025. Also in 2024, the MISO approved a first set of second tranche projects. A portion of these projects were assigned to Ameren and are estimated to cost approximately $1.3 billion, based on the MISO’s cost estimate. The first set of second tranche projects also includes competitive bid projects that are estimated to cost $6.5 billion, which includes projects located in Illinois that are estimated to cost $1.8 billion, based on the MISO’s cost estimate. The competitive bid process is expected to take place through 2026. Separately, in July 2025, the FERC approved transmission rate incentives relating to the second tranche projects assigned to Ameren. The incentives will allow construction work in progress to be included in rate base for projects constructed by ATXI, thereby improving the timeliness of cash recovery, and would allow recovery of prudently incurred costs, subject to FERC approval, for any portion of the projects if they are abandoned for reasons beyond the control of Ameren. ATXI will not capitalize allowance for funds used during construction on the related projects. The MISO is conducting future long-range transmission scenario planning and is expected to issue a final report in early 2026.
•In 2025, the presidential administration issued several executive orders on environmental regulations and enforcement. Many of these actions require further implementation by the EPA, and some of these actions will likely be subject to further judicial review. Grid reliability, environmental, or other regulations, including those related to CO 2 or other emissions, or other executive orders or other actions taken by federal or state regulators, including federal orders related to planned retirements of coal-fired power plants, could result in significant changes in capital expenditures and operating costs. Regulations can be reviewed and repealed, and replacement or alternative regulations can be proposed or adopted by the regulatory agencies, including the EPA. See Note 9 – Commitments and Contingencies under Part I, Item 1, of this report, for additional information on environmental matters. The ultimate implementation of any of these new regulations, as well as the timing of any such implementation, is uncertain. Ameren Missouri’s operating costs and capital expenditures are subject to MoPSC prudence reviews, which could result in cost disallowances, as well as regulatory lag. The cost of Ameren Illinois’ purchased power and natural gas purchased for resale could increase. However, Ameren Illinois expects that these costs would be recovered from customers with no material adverse effect on its results of operations, financial position, or liquidity. Ameren’s and Ameren Missouri’s earnings could benefit from increased investment to comply with environmental regulations if those investments are reflected and recovered on a timely basis in customer rates.
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•The Ameren Companies have multiyear credit agreements that cumulatively provide $2.6 billion of credit through December 2028, subject to a 364-day repayment term for Ameren Missouri and Ameren Illinois, with the option to seek incremental commitments to increase the cumulative credit provided to $3.2 billion. See Note 3 – Short-term Debt and Liquidity under Part I, Item 1, of this report and Note 4 – Short-term Debt and Liquidity under Part II, Item 8, of the Form 10-K for additional information regarding the Credit Agreements. See Note 5 – Long-term Debt and Equity Financings under Part II, Item 8, of the Form 10-K for long-term debt maturities from 2025 to 2029 and beyond at Ameren (parent), Ameren Missouri, Ameren Illinois, and ATXI. See Note 4 – Long-term Debt and Equity Financings under Part I, Item 1, of this report for outstanding forward sale agreements, including under the ATM program, and issuances and maturities of long-term debt in 2025 through the date of this report. Ameren (parent) entered into interest rate swaps to hedge a portion of its interest rate risk on cash flows related to certain forecasted debt issuances to occur in 2026 and 2027. The use of cash provided by operating activities and short-term borrowings to fund capital expenditures and other long-term investments at the Ameren Companies frequently results in a working capital deficit, defined as current liabilities exceeding current assets, as was the case at September 30, 2025, for Ameren. Ameren, Ameren Missouri, and Ameren Illinois each believe that their liquidity is adequate given their respective expected operating cash flows, capital expenditures, and financing plans, and expect to continue to have access to the capital and credit markets on reasonable terms when needed. However, there can be no assurance that significant changes in economic conditions, disruptions in the capital and credit markets, or other unforeseen events will not materially affect their ability to execute their expected operating, capital, or financing plans.
•Ameren expects its cash used for currently planned capital expenditures and dividends to exceed cash provided by operating activities over the next several years. As part of its funding plan for capital expenditures, Ameren is using newly-issued shares of common stock to satisfy requirements under the DRPlus and employee benefit plans and expects to continue to do so through at least 2029. Additionally, 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 September 30, 2025, Ameren had multiple forward sale agreements that could be settled with various counterparties relating to 12.2 million shares of common stock. Ameren expects to settle approximately $530 million of the forward sale agreements with physical delivery of 5.8 million shares of common stock by December 31, 2025 and to settle another approximately $590 million of the forward sale agreements with physical delivery of 6.4 million shares of common stock by December 31, 2026. Including issuances under the DRPlus and employee benefit plans, Ameren plans to issue approximately $600 million of equity each year from 2025 to 2029. In August 2025, Ameren increased the amount of common stock available for sale under the ATM program by $1.25 billion to a total of $3 billion. As of September 30, 2025, Ameren had approximately $1.5 billion of common stock remaining available for sale under the ATM program. The Ameren Companies expect their equity to total capitalization and cash flow metrics to support solid investment-grade credit ratings. Ameren Missouri and Ameren Illinois expect to fund cash flow needs through debt issuances, cash provided by operating activities, and/or capital contributions from Ameren (parent).
•The IRA was enacted in 2022, and includes various income tax provisions, among other things. The law extends federal production and investment tax credits for projects that began construction through 2024 and creates renewable energy production and investment tax credits and nuclear production tax credits for projects beginning construction after 2024, subject to the phase out provisions established by the OBBBA as discussed below. The law allows for transferability, subject to revisions made by the OBBBA discussed below, to an unrelated party for cash of up to 100% of certain tax credits generated after 2022.
•The OBBBA was enacted in July 2025 and includes various income tax provisions, among other things. The OBBBA modified provisions of the IRA related to production and investment tax credits. The new law maintains production and investment tax credits for solar and wind projects that begin construction within one year of the OBBBA’s enactment and are placed in-service by the end of 2030. Projects that begin construction after one year from enactment of the OBBBA but are placed in service by the end of 2027 also remain eligible. The law provides investment tax credits for battery storage projects that begin construction by the end of 2033 and phase out by the end of 2035. Renewable energy projects that begin construction in 2026 and beyond that use a certain threshold percentage of materials from prohibited foreign entities, as defined in the OBBBA, are not eligible for the tax credits. Production tax credits associated with nuclear generation remain unchanged from the IRA and phase out by the end of 2032. Furthermore, the new law continues to allow for transferability of the production and investment tax credits to an unrelated party for cash but is restricted from being transferred to specified foreign entities, as defined in the OBBBA. Ameren is currently evaluating the OBBBA and guidance issued in connection with the OBBBA and does not expect any material impacts on its results of operations, financial position, and liquidity in 2025. Implementation of the OBBBA provisions is subject to additional guidance, regulations, interpretations, amendments, or technical corrections that may be issued by the IRS or United States Department of Treasury.
•Pursuant to the IRA and the OBBBA discussed above, Ameren Missouri expects to transfer production and investment tax credits to unrelated parties of approximately $1.5 billion from 2025 to 2029. Proceeds from these transfers are included in Ameren Missouri’s tracker related to production and investment tax credits allowed under the IRA and the OBBBA or the RESRAM and are ultimately refunded to customers.
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•In 2024, the IRS issued a series of private letter rulings to another taxpayer which provided guidance on applying IRS normalization rules to the calculation of tax benefits related to net operating loss carryforwards. The rulings concluded, that for ratemaking purposes, net operating loss carryforwards should be reflected on a separate company basis and should not be reduced by payments received for the utilization of losses by other affiliates under a tax allocation agreement. While a private letter ruling issued to another taxpayer may not be relied on as precedent, Ameren Illinois is evaluating this guidance and is addressing potential impacts of the private letter rulings with the ICC. These impacts could result in reductions to income tax expense at Ameren Illinois’ electric and natural gas distribution businesses of $25 million and $13 million, respectively. Ameren Illinois will record the impacts, if any, if approved by the ICC in its 2024 electric distribution service revenue requirement reconciliation adjustment proceeding and in its January 2025 natural gas rate review.
•As of September 30, 2025, Ameren had $177 million in tax benefits from federal and state income tax credit carryforwards, $55 million in tax benefits from federal and state net operating loss carryforwards, and $23 million in tax receivables, which will be utilized in future periods. Future expected income tax payments are based on expected taxable income, available income tax credit and net operating loss carryforwards, and current tax law. Expected taxable income is affected by expected capital expenditures, when property, plant, and equipment is placed in-service or retired, and the timing of regulatory reviews, among other things. Ameren expects annual federal income tax payments to be immaterial through 2029.
The above items could have a material impact on our results of operations, financial position, and liquidity. Additionally, in the ordinary course of business, we evaluate strategies to enhance our results of operations, financial position, and liquidity. These strategies may include acquisitions, divestitures, opportunities to reduce costs or increase revenues, and other strategic initiatives to increase Ameren’s shareholder value. We are unable to predict which, if any, of these initiatives will be executed. The execution of these initiatives may have a material impact on our future results of operations, financial position, or liquidity.
REGULATORY MATTERS
See Note 2 – Rate and Regulatory Matters under Part I, Item 1, of this report.
ITEM 3. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK.
There have been no material changes to the quantitative and qualitative disclosures about interest rate risk, credit risk, commodity price risk, investment price risk, and commodity supplier risk included in the Form 10-K. See Item 7A under Part II of the Form 10-K for a more detailed discussion of our market risk.
ITEM 4. CONTROLS AND PROCEDURES.
(a)Evaluation of Disclosure Controls and Procedures
As of September 30, 2025, evaluations were performed under the supervision and with the participation of management, including the principal executive officer and the principal financial officer of each of the Ameren Companies, of the effectiveness of the design and operation of such registrant’s disclosure controls and procedures (as defined in Rules 13a-15(e) and 15d-15(e) of the Exchange Act). Based on those evaluations, as of September 30, 2025, the principal executive officer and the principal financial officer of each of the Ameren Companies concluded that such disclosure controls and procedures are effective to provide assurance that information required to be disclosed in such registrant’s reports filed or submitted under the Exchange Act is recorded, processed, summarized, and reported within the time periods specified in the SEC’s rules and forms and such information is accumulated and communicated to its management, including its principal executive officer and its principal financial officer, to allow timely decisions regarding required disclosure.
(b)Changes in Internal Controls over Financial Reporting
There has been no change in any of the Ameren Companies’ internal control over financial reporting during their most recent fiscal quarter that has materially affected, or is reasonably likely to materially affect, each of their internal control over financial reporting.
PART II. OTHER INFORMATION
ITEM 1. LEGAL PROCEEDINGS.
We are involved in legal and administrative proceedings before various courts and agencies with respect to matters that arise in the ordinary course of business, some of which involve substantial amounts of money. We believe that the final disposition of these proceedings, except as otherwise disclosed in this report, will not have a material adverse effect on our results of operations, financial position, or liquidity. Risk of loss is mitigated, in some cases, by insurance or contractual or statutory indemnification. We believe that we have established appropriate reserves for potential losses. For additional information on material legal and administrative proceedings, see Note 2 – Rate and Regulatory Matters, Note 9 – Commitments and Contingencies, and Note 10 – Callaway Energy Center, under Part I, Item 1, of this report.
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Pursuant to Item 103(c)(3)(iii) of Regulation S-K, our policy is to disclose environmental proceedings to which a governmental entity is a party if we reasonably believe such proceedings will result in monetary sanctions of $1 million or more.
ITEM 1A. RISK FACTORS.
For a detailed discussion of our risk factors, see the information disclosed in Part I, Item 1A, of the Form 10-K.
ITEM 2. UNREGISTERED SALES OF EQUITY SECURITIES AND USE OF PROCEEDS.
Ameren Corporation, Ameren Missouri, and Ameren Illinois did not purchase equity securities reportable under Item 703 of Regulation S-K during the period from July 1, 2025, to September 30, 2025.
ITEM 5. OTHER INFORMATION.
Insider Adoption or Termination of Trading Arrangements
During the fiscal quarter ended September 30, 2025, none of our directors or officers informed us of the adoption or termination of a “Rule 10b5-1 trading arrangement” or “non-Rule 10b5-1 trading arrangement,” as those terms are defined in Regulation S-K, Item 408, except as follows:
On August 13, 2025, Theresa A. Shaw, Senior Vice President, Finance and Chief Accounting Officer of Ameren, adopted a Rule 10b5-1 trading arrangement that provides for the sale of an aggregate of up to 1,300 shares to be sold in four equal quarterly installments between November 2025 and November 2026, subject to certain price limitations set forth in the trading arrangement. Ms. Shaw’s 10b5-1 trading arrangement will terminate on the earlier of: (i) November 13, 2026; (ii) execution of all trades or expiration of all orders relating to such trades under the Rule 10b5-1 trading arrangement; or (iii) such date as the Rule 10b5-1 trading arrangement is otherwise terminated according to its terms.
The trading arrangement discussed above is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c).
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ITEM 6. EXHIBITS.
The documents listed below are being filed or have previously been filed on behalf of the Ameren Companies and are incorporated herein by reference from the documents indicated and made a part hereof. Exhibits not identified as previously filed are filed herewith.

Exhibit Designation |  | Registrant(s) |  | Nature of Exhibit |  | Previously Filed as Exhibit to:
Rule 13a-14(a) / 15d-14(a) Certifications
31.1 |  | Ameren |  | Rule 13a-14(a)/15d-14(a) Certification of Principal Executive Officer of Ameren |  |
31.2 |  | Ameren |  | Rule 13a-14(a)/15d-14(a) Certification of Principal Financial Officer of Ameren |  |
31.3 |  | Ameren Missouri |  | Rule 13a-14(a)/15d-14(a) Certification of Principal Executive Officer and Principal Financial Officer of Ameren Missouri |  |
31.4 |  | Ameren Illinois |  | Rule 13a-14(a)/15d-14(a) Certification of Principal Executive Officer of Ameren Illinois |  |
31.5 |  | Ameren Illinois |  | Rule 13a-14(a)/15d-14(a) Certification of Principal Financial Officer of Ameren Illinois |  |
Section 1350 Certifications
32.1 |  | Ameren |  | Section 1350 Certification of Principal Executive Officer and Principal Financial Officer of Ameren |  |
32.2 |  | Ameren Missouri |  | Section 1350 Certification of Principal Executive Officer and Principal Financial Officer of Ameren Missouri |  |
32.3 |  | Ameren Illinois |  | Section 1350 Certification of Principal Executive Officer and Principal Financial Officer of Ameren Illinois |  |
Interactive Data Files
101.INS |  | Ameren Companies |  | Inline XBRL Instance Document - the instance document does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document |  |
101.SCH |  | Ameren Companies |  | Inline XBRL Taxonomy Extension Schema Document |  |
101.CAL |  | Ameren Companies |  | Inline XBRL Taxonomy Extension Calculation Linkbase Document |  |
101.LAB |  | Ameren Companies |  | Inline XBRL Taxonomy Extension Label Linkbase Document |  |
101.PRE |  | Ameren Companies |  | Inline XBRL Taxonomy Extension Presentation Linkbase Document |  |
101.DEF |  | Ameren Companies |  | Inline XBRL Taxonomy Extension Definition Document |  |
104 |  | Ameren Companies |  | Cover Page Interactive Data File (formatted as Inline XBRL and contained in Exhibit 101) |  |

The file number references for the Ameren Companies’ filings with the SEC are: Ameren, 1-14756; Ameren Missouri, 1-2967; and Ameren Illinois, 1-3672.
Each registrant hereby undertakes to furnish to the SEC upon request a copy of any long-term debt instrument not listed above that such registrant has not filed as an exhibit pursuant to the exemption provided by Item 601(b)(4)(iii)(A) of Regulation S-K.
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SIGNATURES
Pursuant to the requirements of the Exchange Act, each registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized. The signature for each undersigned company shall be deemed to relate only to matters having reference to such company or its subsidiaries.

AMEREN CORPORATION (Registrant)
/s/ Michael L. Moehn
Michael L. Moehn Senior Executive Vice President and Chief Financial Officer (Principal Financial Officer)
UNION ELECTRIC COMPANY (Registrant)
/s/ Michael L. Moehn
Michael L. Moehn Interim Chairman and President, Senior Executive Vice President and Chief Financial Officer (Principal Executive Officer and Principal Financial Officer)
AMEREN ILLINOIS COMPANY (Registrant)
/s/ Michael L. Moehn
Michael L. Moehn Senior Executive Vice President and Chief Financial Officer (Principal Financial Officer)

Date: November 6, 2025
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