UNION ELECTRIC CO - Quarter Report: 2025 June (Form 10-Q)

Other Income, Net Interest Charges Income Before Income Taxes Income Taxes Net Income Less: Net Income Attributable to Noncontrolling Interests Net Income Attributable to Ameren Common Shareholders$ $ $ $ Net Income$ $ $ $ Other Comprehensive Loss, Net of Taxes

Pension and other postretirement benefit plan activity, net of income taxes (benefit) of $(), $(), $(), and $() respectively

()()()()

Unrealized net loss on derivative hedging instruments, net of income taxes (benefit) of $(), $, $(), and $, respectively

() () Comprehensive Income

Less: Comprehensive Income Attributable to Noncontrolling Interests

Comprehensive Income Attributable to Ameren Common Shareholders$ $ $ $ Earnings per Common Share - Basic$ $ $ $ Current regulatory assets Other current assets Total current assets Property, Plant, and Equipment, Net Investments and Other Assets:Nuclear decommissioning trust fund Goodwill

Regulatory assets (includes $ and $ related to VIEs, respectively)

Pension and other postretirement benefits Other assets Total investments and other assets TOTAL ASSETS$ $ LIABILITIES AND EQUITYCurrent Liabilities:

Current maturities of long-term debt (includes $ and $ related to VIEs, respectively)

$ $ Short-term debt Accounts and wages payable Taxes accrued Interest accrued Customer deposits Other current liabilities Total current liabilities

Long-term Debt, Net (includes $ and $ related to VIEs, respectively)

Deferred Credits and Other Liabilities:Accumulated deferred income taxes and tax credits, net Regulatory liabilities Asset retirement obligations Other deferred credits and liabilities Total deferred credits and other liabilities Commitments and Contingencies (Notes 2, 9, and 10) Shareholders’ Equity:

Common stock, $ par value, shares authorized – shares outstanding of and , respectively

Other paid-in capital, principally premium on common stock Retained earnings Accumulated other comprehensive loss()()Total shareholders’ equity Noncontrolling Interests Total equity TOTAL LIABILITIES AND EQUITY$ $

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)
	Six Months Ended June 30,
	2025	2024
Cash Flows From Operating Activities:
Net income	$	$
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization
Amortization of nuclear fuel
Amortization of debt issuance costs and premium/discounts
Deferred income taxes and tax credits, net
Allowance for equity funds used during construction	()	()
Stock-based compensation costs
Other
Changes in assets and liabilities:
Receivables	()	()
Inventories		()
Accounts and wages payable	()	()
Taxes accrued
Regulatory assets and liabilities	()	()
Assets, other	()	()
Liabilities, other
Pension and other postretirement benefits	()	()
Net cash provided by operating activities
Cash Flows From Investing Activities:
Capital expenditures	()	()
Nuclear fuel expenditures	()	()
Purchases of securities – nuclear decommissioning trust fund	()	()
Sales and maturities of securities – nuclear decommissioning trust fund
Other
Net cash used in investing activities	()	()
Cash Flows From Financing Activities:
Dividends on common stock	()	()
Dividends paid to noncontrolling interest holders	()	()
Short-term debt, net	()
Maturities and extinguishment of long-term debt	()	()
Issuances of long-term debt
Issuances of common stock
Employee payroll taxes related to stock-based compensation	()	()
Debt issuance costs	()	()
Net cash provided by financing activities
Net change in cash, cash equivalents, and restricted cash
Cash, cash equivalents, and restricted cash at beginning of year
Cash, cash equivalents, and restricted cash at end of period	$	$

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 June 30,			Six Months Ended June 30,
	2025		2024	2025	2024
Common Stock	$		$	$	$

Other Paid-in Capital:
Beginning of period
Shares issued under the DRPlus and 401(k) plan
Stock-based compensation activity
Other paid-in capital, end of period

Retained Earnings:
Beginning of period
Net income attributable to Ameren common shareholders
Dividends on common stock	()		()	()	()
Retained earnings, end of period

Accumulated Other Comprehensive Loss:
Derivative financial instruments, beginning of period	$	()
Change in derivative financial instruments	()			()
Derivative financial instruments, end of period	()			()
Deferred retirement benefit costs, beginning of period	()		()	()	()
Change in deferred retirement benefit costs	()		()	()	()
Deferred retirement benefit costs, end of period	()		()	()	()
Total accumulated other comprehensive loss, end of period	()		()	()	()
Total Shareholders’ Equity	$		$	$	$

Noncontrolling Interests:
Beginning of period
Net income attributable to noncontrolling interest holders
Dividends paid to noncontrolling interest holders	()		()	()	()
Noncontrolling interests, end of period
Total Equity	$		$	$	$


Common stock shares outstanding at beginning of period
Shares issued under the DRPlus and 401(k) plan
Shares issued for stock-based compensation
Common stock shares outstanding at end of period

Dividends per common share	$		$	$	$

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 June 30,

Six Months Ended June 30,

2025

2024

2025

2024

Operating Revenues:

Electric

Natural gas

Total operating revenues

Operating Expenses:

Fuel and purchased power

Natural gas purchased for resale

Other operations and maintenance

Depreciation and amortization

Taxes other than income taxes

Total operating expenses

Operating Income

Other Income, Net

Interest Charges

Income Before Income Taxes

Income Taxes

Net Income

Preferred Stock Dividends

Net Income Available to Common Shareholder

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)


	June 30, 2025	December 31, 2024
ASSETS
Current Assets:
Cash and cash equivalents	$	$
Advances to money pool
Accounts receivable – trade (less allowance for doubtful accounts of $ and $, respectively)
Accounts receivable – affiliates
Unbilled revenue
Miscellaneous accounts receivable
Inventories
Current regulatory assets
Other current assets
Total current assets
Property, Plant, and Equipment, Net
Investments and Other Assets:
Nuclear decommissioning trust fund
Regulatory assets (includes $ and $ related to VIEs, respectively)
Pension and other postretirement benefits
Other assets
Total investments and other assets
TOTAL ASSETS	$	$
LIABILITIES AND SHAREHOLDERS’ EQUITY
Current Liabilities:
Current maturities of long-term debt (includes $ and $ related to VIEs, respectively)	$	$
Short-term debt
Accounts and wages payable
Accounts payable – affiliates
Taxes accrued
Interest accrued
Other current liabilities
Total current liabilities
Long-term Debt, Net (includes $ and $ related to VIEs, respectively)
Long-term Debt, Net - Related Parties
Deferred Credits and Other Liabilities:
Accumulated deferred income taxes and tax credits, net
Regulatory liabilities
Asset retirement obligations
Other deferred credits and liabilities
Total deferred credits and other liabilities
Commitments and Contingencies (Notes 2, 8, 9, and 10)
Shareholders’ Equity:
Common stock, $ par value, shares authorized – shares outstanding
Other paid-in capital, principally premium on common stock
Preferred stock
Retained earnings
Total shareholders’ equity
TOTAL LIABILITIES AND SHAREHOLDERS’ EQUITY	$	$

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)


	Six Months Ended June 30,
	2025	2024
Cash Flows From Operating Activities:
Net income	$	$
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization
Amortization of nuclear fuel
Amortization of debt issuance costs and premium/discounts
Deferred income taxes and tax credits, net
Allowance for equity funds used during construction	()	()
Other
Changes in assets and liabilities:
Receivables	()	()
Inventories		()
Accounts and wages payable	()	()
Taxes accrued
Regulatory assets and liabilities	()	()
Assets, other	()	()
Liabilities, other
Pension and other postretirement benefits	()	()
Net cash provided by operating activities
Cash Flows From Investing Activities:
Capital expenditures	()	()
Nuclear fuel expenditures	()	()
Purchases of securities – nuclear decommissioning trust fund	()	()
Sales and maturities of securities – nuclear decommissioning trust fund
Money pool advances, net
Net cash used in investing activities	()	()
Cash Flows From Financing Activities:
Dividends on common stock	()
Dividends on preferred stock	()	()
Short-term debt, net
Money pool borrowings, net		()
Maturities of long-term debt		()
Issuances of long-term debt
Capital contribution from parent
Debt issuance costs	()	()
Net cash provided by financing activities
Net change in cash, cash equivalents, and restricted cash
Cash, cash equivalents, and restricted cash at beginning of year
Cash, cash equivalents, and restricted cash at end of period	$	$

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 June 30,		Six Months Ended June 30,
	2025	2024	2025	2024
Common Stock	$	$	$	$

Other Paid-in Capital
Beginning of period
Capital contributions from parent
Other paid-in capital, end of period

Preferred Stock

Retained Earnings:
Beginning of period
Net income
Dividends on common stock			()
Dividends on preferred stock	()	()	()	()
Retained earnings, end of period

Total Shareholders’ Equity	$	$	$	$

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 June 30,

Six Months Ended June 30,

2025

2024

2025

2024

Operating Revenues:

Electric

Natural gas

Total operating revenues

Operating Expenses:

Purchased power

Natural gas purchased for resale

Other operations and maintenance

Depreciation and amortization

Taxes other than income taxes

Total operating expenses

Operating Income

Other Income, Net

Interest Charges

Income Before Income Taxes

Income Taxes

Net Income

Preferred Stock Dividends

Net Income Available to Common Shareholder

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)


	June 30, 2025	December 31, 2024
ASSETS
Current Assets:
Cash and cash equivalents	$	$
Accounts receivable – trade (less allowance for doubtful accounts of $ and $, respectively)
Accounts receivable – affiliates
Unbilled revenue
Miscellaneous accounts receivable
Inventories
Prepaid assets
Current regulatory assets
Other current assets
Total current assets
Property, Plant, and Equipment, Net
Investments and Other Assets:
Goodwill
Regulatory assets
Pension and other postretirement benefits
Other assets
Total investments and other assets
TOTAL ASSETS	$	$
LIABILITIES AND SHAREHOLDERS’ EQUITY
Current Liabilities:
Current maturities of long-term debt	$	$
Short-term debt
Borrowings from money pool
Accounts and wages payable
Accounts payable – affiliates
Interest accrued
Customer deposits
Current regulatory liabilities
Other current liabilities
Total current liabilities
Long-term Debt, Net
Long-term Debt, Net – Related Parties
Deferred Credits and Other Liabilities:
Accumulated deferred income taxes and tax credits, net
Regulatory liabilities
Other deferred credits and liabilities
Total deferred credits and other liabilities
Commitments and Contingencies (Notes 2, 8, and 9)
Shareholders’ Equity:
Common stock, par value, shares authorized – shares outstanding
Other paid-in capital
Preferred stock
Retained earnings
Total shareholders’ equity
TOTAL LIABILITIES AND SHAREHOLDERS’ EQUITY	$	$

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)


	Six Months Ended June 30,
	2025	2024
Cash Flows From Operating Activities:
Net income	$	$
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization
Amortization of debt issuance costs and premium/discounts
Deferred income taxes and tax credits, net
Allowance for equity funds used during construction	()	()
Other
Changes in assets and liabilities:
Receivables	()
Inventories
Accounts and wages payable
Taxes accrued	()
Regulatory assets and liabilities	()	()
Assets, other	()	()
Liabilities, other
Pension and other postretirement benefits	()	()
Net cash provided by operating activities
Cash Flows From Investing Activities:
Capital expenditures	()	()
Money pool advances, net		()
Other	()
Net cash used in investing activities	()	()
Cash Flows From Financing Activities:
Dividends on common stock	()	()
Dividends on preferred stock	()	()
Short-term debt, net		()
Money pool borrowings, net	()	()
Maturities of long-term debt	()
Issuances of long-term debt
Debt issuance costs	()	()
Net cash provided by financing activities
Net change in cash, cash equivalents, and restricted cash
Cash, cash equivalents and restricted cash at beginning of year
Cash, cash equivalents, and restricted cash at end of period	$	$

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 June 30,		Six Months Ended June 30,
	2025	2024	2025	2024
Common Stock	$	$	$	$

Other Paid-in Capital

Preferred Stock

Retained Earnings:
Beginning of period
Net income
Dividends on common stock		()	()	()
Dividends on preferred stock	()	()	()	()
Retained earnings, end of period

Total Shareholders’ Equity	$	$	$	$

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)

June 30, 2025

NOTE 1 –

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.

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Other current assets(a)

(a)In-service dates are dependent on the timing of regulatory approvals and construction completion, among other things.

(b)These projects collectively represent approximately $ billion of capital expenditures.

(c)FERC approval of acquisition received November 2024.

(d)This project represents approximately $ 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 $ million, $ million, $ million, and $ 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 $ 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.

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 July 2025, Ameren Illinois filed a revised reconciliation adjustment, requesting recovery of $ million. The adjustment reflects Ameren Illinois’ actual 2024 recoverable costs, 2024 year-end rate base, and a capital structure composed of % common equity. In July 2025, the ICC staff submitted its calculation of the reconciliation adjustment, recommending recovery of $ 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 rates by $ million with the ICC. An ICC decision in this proceeding is required by December 2025, with new rates effective in January 2026.

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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. A decision by the ICC in this proceeding is expected by September 2025.

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 $ million. The request is based on a % ROE, a capital structure composed of % common equity, and a rate base of $ billion. Ameren Illinois used a 2026 future test year in this proceeding. In July 2025, the ICC staff recommended an increase to annual revenues for natural gas delivery service of $ million. The recommendation is based on a % ROE, a capital structure composed of % common equity, and a rate base of $ billion. In addition, in July 2025, the Illinois Attorney General's office recommended an increase to annual revenues for natural gas delivery service of $ million, based on a % ROE, a capital structure composed of % common equity, and a rate base of $ billion. A decision by the ICC in this proceeding is required by early December 2025, with new rates expected to be effective in 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 $ 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.

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 % to % and required refunds, with interest, for the periods from November 2013 to February 2015 and from late September 2016 forward. In November 2024, the MISO transmission owners, including Ameren Missouri, Ameren Illinois, and ATXI, filed a request for rehearing with the FERC, arguing, among other things, the FERC should not have ordered refunds back to September 2016 or imposed interest on those refunds. Also in November 2024, another intervenor filed a request for rehearing with the FERC, requesting the FERC change aspects of the ROE methodology used in the October 2024 order and reconsider its decision in a February 2015 complaint case to deny refunds for the period from February 2015 to May 2016. 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. 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 June 30, 2025, Ameren and Ameren Illinois had recorded liabilities in "Current regulatory liabilities" on their balance sheets of $ million and $ million, respectively, to reflect the expected refunds, including interest, associated with the allowed base ROE set by the October 2024 order.

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NOTE 3 –

billion. The Ameren Companies were in compliance with the covenants in their Credit Agreements as of June 30, 2025. As of June 30, 2025, the ratios of consolidated indebtedness to consolidated total capitalization, calculated in accordance with the provisions of the Credit Agreements, were %, %, and % for Ameren, Ameren Missouri, and Ameren Illinois, respectively. $ Ameren Missouri Ameren Illinois Ameren consolidated$ $

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 six months ended June 30, 2025 and 2024:


	Ameren (parent)		Ameren Missouri		Ameren Illinois		Ameren Consolidated
2025
Average daily amount outstanding	$		$		$		$

Weighted-average interest rate		%		%		%		%
Peak amount outstanding during period(a)	$		$		$		$
Peak interest rate		%		%		%		%
2024
Average daily amount outstanding	$		$		$		$

Weighted-average interest rate		%		%		%		%
Peak amount outstanding during period(a)	$		$		$		$
Peak interest rate		%		%		%		%

(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.

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 six months ended June 30, 2025, was % and % (2024 – % and %). 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 six months ended June 30, 2025 and 2024.

NOTE 4 –

million and million shares of common stock, under its DRPlus and 401(k) plan, and received proceeds of $ million and $ million. As of June 30, 2025, Ameren had a receivable of $ million related to issuances of common stock under its DRPlus and 401(k) plan. In addition, in the first quarter of 2025, Ameren issued million shares of common stock valued at $ million upon the settlement of stock-based compensation awards.

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billion of its common stock through an ATM program, which includes the ability to enter into forward sale agreements. There were no shares issued under the ATM program during the three and six months ended June 30, 2025. As of June 30, 2025, Ameren had approximately $ million of common stock available for sale under the ATM program, which takes into account the forward sale agreements in effect as of June 30, 2025, discussed below.

Forward sale agreements for million shares, outstanding as of June 30, 2025 under the ATM program, 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 $ to $, with an average initial forward sale price of $. Additionally in May 2025, Ameren entered into forward sale agreements separate from the ATM program with multiple counterparties relating to 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 $ 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 June 30, 2025, Ameren could have settled the forward sale agreements with physical delivery of million shares of common stock to the respective counterparties in exchange for cash of $ billion. Alternatively, the forward sale agreements could have also been net settled at June 30, 2025, with delivery of approximately $ million of cash or approximately million shares of common stock to the counterparties. In connection with the forward sale agreements outstanding at June 30, 2025, the various counterparties, or their affiliates, borrowed from third parties and sold million shares of common stock. The gross sales price of these shares totaled $ 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 $ million of % 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 $ 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 $ million, which is reflected in “Other Income, Net” on Ameren’s consolidated statement of income. Interest expense related to repurchased bonds was $ million for both the three and six months ended June 30, 2025.

Ameren Missouri

In April 2025, Ameren Missouri issued $ million of % 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.

Ameren Illinois

In March 2025, Ameren Illinois issued $ million of % first mortgage bonds due March 2055, with interest payable semiannually on March 1 and September 1 of each year, beginning September 1, 2025. Net proceeds from this issuance were used to repay $ million principal amount of its % senior secured notes that matured in March 2025 and 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 June 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 June 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.

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NOTE 5 –

$ $ $

Other interest income

Non-service cost components of net periodic benefit income(a)

Miscellaneous income

Gain on the extinguishment of debt(b)

Earnings (losses) related to equity method investments() ()

Donations

()()()()

Miscellaneous expense

()()()()Total Other Income, Net$ $ $ $ Ameren Missouri:

Allowance for equity funds used during construction

$ $ $ $

Other interest income

Non-service cost components of net periodic benefit income(a)

Miscellaneous income

Donations

()()()()

Miscellaneous expense

()()()()Total Other Income, Net$ $ $ $ Ameren Illinois:

Allowance for equity funds used during construction

$ $ $ $ Other interest income

Non-service cost components of net periodic benefit income

Miscellaneous income

Donations

()()()Miscellaneous expense()()()()Total Other Income, Net$ $ $ $

(a)For the three and six months ended June 30, 2025, the non-service cost components of net periodic benefit income were adjusted by amounts deferred of $() million and $() 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 $() million and $() million, respectively, for the three and six months ended June 30, 2024. See Note 11 – Retirement Benefits for additional information.

NOTE 6 –

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As of June 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 discussed below do not receive regulatory deferral and were included in accumulated OCI. 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 June 30, 2025, and December 31, 2024, Ameren had interest rate swaps with notional amounts of $ million and $ million respectively. Ameren recorded an unrealized loss, net of income tax benefits, on the change in fair value of interest rate swaps of $ million and $ million to "Accumulated other comprehensive loss" for the three and six months ended June 30, 2025.

Natural gas (in mmbtu) Power (in MWhs) Other assets PowerOther current assets Total assets$ $ $ $ $ $ Fuel oilsOther current liabilities$ $ $ $ $ $ Other deferred credits and liabilities Natural gasOther current liabilities Other deferred credits and liabilities PowerOther current liabilities Other deferred credits and liabilities Total liabilities$ $ $ $ $ $

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 June 30, 2025, and December 31, 2024.

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NOTE 7 –

Power Total derivative assets – commodity contracts$ $ $ $ $ $ $ $ Nuclear decommissioning trust fund:Equity securities:U.S. large capitalization$ $ $ $ $ $ $ $ Debt securities:U.S. Treasury and agency securities Corporate bonds Other Total nuclear decommissioning trust fund$ $ $ $

(a)

$ $ $ $

(a)

Total Ameren Missouri$ $ $ $ $ $ $ $

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$ $ $ $ $ $ $ Total Ameren Illinois$ $ $ $ $ $ $ $ Ameren

Derivative assets – commodity contracts(b)

$ $ $ $ $ $ $ $

Nuclear decommissioning trust fund(c)

(a)

Total Ameren$ $ $ $ $ $ $ $ Liabilities:Ameren MissouriDerivative liabilities – commodity contracts:Fuel oils$ $ $ $ $ $ $ $ Natural gas () )() ) () )() Level 3TotalJune 30, 2025 $

(c)

$ December 31, 2024 $

(c)

(a)Included unamortized debt issuance costs, which were excluded from the fair value measurement, of $ million, $ million, and $ million for Ameren, Ameren Missouri, and Ameren Illinois, respectively, as of June 30, 2025. Included unamortized debt issuance costs, which were excluded from the fair value measurement, of $ million, $ million, and $ 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).

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 –

million and $ million, respectively, as of June 30, 2025, and $ million and $ 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.

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$$$

Income taxes receivable from parent(b)

(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

$ $ $

rent and facility services

2024 (b) (b)Ameren Missouri and Ameren Illinois miscellaneousOperating Revenues2025$(b)$ $(b)$ support services2024 (b) Total Operating Revenues2025$ $ $ $ 2024 (b) Ameren Missouri and Ameren IllinoisPurchased Power2025$ $ $ $ transmission services from ATXI2024 Ameren Missouri and Ameren IllinoisOther Operations and Maintenance2025$(b)$ $(b)$

rent and facility services

2024(b)(b)(b)(b)Ameren Services support servicesOther Operations and Maintenance2025$ $ $ $

agreement

2024 Total Other Operations and2025$ $ $ $ Maintenance2024 Money pool interest(Interest Charges)/Other Income, Net2025$(b)$(b)$(b)$(b)2024(b)(b)()()Long-term debt, net - related parties(Interest Charges)2025$()$(b)$()$(b)2024

(a)Not applicable.

(b)Amount less than $ million.

NOTE 9 –

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million to $ 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.

Clean Air Act

Federal and state laws, including the CSAPR, regulate emissions of SO2 and NOx 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 NOx 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 work 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 scrubbers at its Sioux Energy Center, and optimization of existing NOx air pollution control equipment. If the EPA repeals the currently stayed Good Neighbor Rule, Ameren Missouri would not expect additional NOx controls at its coal-fired energy centers to be necessary.

CO2 Emissions Standards

In April 2024, the EPA issued a final rule that sets CO2 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.

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million associated with CCR storage facilities recorded on their respective balance sheets as of June 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.

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 June 30, 2025, Ameren Illinois has remediated the majority of the former MGP sites in Illinois with an estimated remaining obligation primarily related to of these former MGP sites at $ million to $ million. Ameren and Ameren Illinois recorded a liability of $ 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.

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NOTE 10 –

million have historically been included in the costs used to establish electric rates for Ameren Missouri’s customers. Every , 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 $ million to , 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

$ Pool participation

(a)

(b)

(c)

$ Property damage:NEIL and EMANIApril 1, 2025$

(d)

(e)

Accidental outage:NEILApril 1, 2025$

(f)

(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 $ million in the event of an incident at any licensed United States commercial reactor, payable at $ million per year.

(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 $ billion in property damage, stabilization, decontamination, and premature decommissioning insurance for radiation events and $ billion in property damage insurance for nonradiation events. EMANI provides $ 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 $ million for 52 weeks, which commences after the first 12 weeks of an outage, plus up to $ million per week for a minimum of 71 weeks thereafter for a total not exceeding the policy limit of $ million. Nonradiation events are limited to $ 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 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 $ billion within a 12-month period for radiation events, or $ 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.

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NOTE 11 –

$ $ $ $ $ $ $ Non-service cost components:Interest cost

Expected return on plan assets(b)

()()()()()()()()

Amortization of(b):

Prior service cost (credit) ()()()()Actuarial (gain)()()()()()()()()

Total non-service cost components(c)

$()$()$()$()$()$()$()$()

Net periodic benefit income(d)

$()$()$()$()$()$()$()$()

(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 years. The difference between the actual and expected return on plan assets is amortized over 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.

Ameren Missouri and Ameren Illinois are responsible for their respective share of Ameren’s pension and other postretirement costs.

)$()$()$()$()$()$()$()Ameren Illinois ()()()()()()()Other ()()()

Ameren(a)

$()$()$()$()$()$()$()$()

(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.

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NOTE 12 –

% % % % % %Increases (decreases) from:

Amortization of excess deferred taxes(a)

()()()()()()Amortization of deferred investment tax credit() ()

Renewable and other tax credits(b)

()()()() State tax Depreciation differences()()()()() Effective income tax rate % % % % % %Six MonthsFederal statutory corporate income tax rate % % % % % %Increases (decreases) from:

Amortization of excess deferred taxes(a)

()()

()()Amortization of deferred investment tax credit() ()

Renewable and other tax credits(b)

()()()() State tax Effective income tax rate % % % % % %

(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)The benefit of the credits associated with Missouri renewable energy standard compliance is refunded to customers through the RESRAM. The benefit of the credits associated with the production and investment tax credit tracker will be refunded to customers based on MoPSC approval in a regulatory rate review.

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NOTE 13 –

$ $ $ $ $ $ $ $ $

(a)

)

(c)

(a)

(a)Balance included $ million in “Other current liabilities” on the balance sheet as of both June 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 performance share units with a grant date fair value of $ million and restricted share units with a grant date fair value of $ million. Awards vest approximately 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 ( performance share units) or clean energy transition targets ( performance share units). The exact number of shares issued pursuant to a performance share unit varies from % to % of the target award, depending on actual company performance relative to the performance goals.

For the six months ended June 30, 2025 and 2024, excess tax benefits (deficiencies) associated with the settlement of stock-based compensation awards decreased income tax expense by $ million and increased income tax expense by $ million, respectively.

million and $ million, respectively, which was primarily reflected in “Other deferred credits and liabilities” on Ameren’s consolidated balance sheet.

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$ $ $ Ameren Illinois Ameren$ $ $ $

Earnings per Share

Assumed settlement of performance share units and restricted stock units Dilutive effect of forward sale agreements

Weighted-average Common Shares Outstanding – Diluted(a)

) ) ) ) ()$

(a)The following table presents increases/(decreases) in revenues from alternative revenue programs and other revenues not from contracts with customers for the three and six months ended June 30, 2025 and 2024:

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$()$ $()$— $()Other revenues not from contracts with customers () Three Months 2024:Revenues from alternative revenue programs$()$ $ $ $— $ Other revenues not from contracts with customers Six Months 2025:Revenues from alternative revenue programs$()$ $ $()$— $ Other revenues not from contracts with customers () Six Months 2024:Revenues from alternative revenue programs$()$ $ $ $— $ Other revenues not from contracts with customers

(b)Includes over-recoveries of various riders.

Ameren Illinois

Ameren Illinois Electric Distribution

Ameren Illinois Natural Gas

Ameren Illinois Transmission

Intersegment Eliminations

Ameren Illinois

Three Months 2025:

Residential

Commercial

Industrial

Other

()

Total revenues(a)

()

Three Months 2024:

Residential

Commercial

Industrial

Other

()

(b)

()

Total revenues(a)

()

Six Months 2025:

Residential

Commercial

Industrial

Other

()

Total revenues(a)

()

Six Months 2024:

Residential

Commercial

Industrial

Other

()

(b)

()

Total revenues(a)

()

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)$ $()$()Other revenues not from contracts with customers Three Months 2024:Revenues from alternative revenue programs$ $ $ $ Other revenues not from contracts with customers Six Months 2025:Revenues from alternative revenue programs$ $ $()$ Other revenues not from contracts with customers Six Months 2024:Revenues from alternative revenue programs$ $ $ $ Other revenues not from contracts with customers

(b)Includes over-recoveries of various riders.

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 June 30, 2025, was $275 million, or $1.01 per diluted share, compared with $258 million, or $0.97 per diluted share, in the year-ago period. Net income attributable to Ameren common shareholders in the six months ended June 30, 2025, was $564 million, or $2.08 per diluted share, compared with $519 million, or $1.95 per diluted share, in the year-ago period. Net income was favorably affected for the three and six months ended June 30, 2025, by increased base rate revenues at Ameren Missouri effective June 1, 2025, pursuant to the April 2025 MoPSC electric rate order, increased deferral of financing costs related to rate base investments associated with the PISA and RESRAM at Ameren Missouri, and increased infrastructure investments at Ameren Transmission and Ameren Illinois Electric Distribution. Earnings were also favorably affected for the three and six months ended June 30, 2025, by a higher allowance for equity funds used during construction at Ameren Transmission, primarily resulting from a decreased level of short-term borrowings included in the calculation and higher average construction work in progress balances. Earnings were favorably affected in the six months ended June 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

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outstanding claims in the NSR and Clean Air Act litigation associated with the Rush Island Energy Center, partially offset by higher Ameren Missouri storm expenses in 2025. Additionally, earnings were favorably affected in the six months ended June 30, 2025, by increased retail electric sales volumes at Ameren Missouri, primarily due to colder winter temperatures in 2025. Net income was unfavorably affected for the three and six months ended June 30, 2025, by increased financing costs, primarily resulting from higher short-term debt balances at Ameren (parent) and higher interest rates on higher debt balances at Ameren Missouri. Additionally, earnings were unfavorably affected in the three months ended June 30, 2025, due to decreased retail electric sales volumes at Ameren Missouri as a result of milder spring and early summer temperatures, when compared to the year-ago period.

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 $2.1 billion in its rate-regulated businesses in the six months ended June 30, 2025.

In April 2025, Missouri Senate Bill 4 was enacted and will become effective in late 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, allow the MoPSC to authorize inclusion of construction work in progress in rate base for new natural gas-fired generation facilities and new generation facilities approved through integrated resource planning, and allow natural gas utilities to file regulatory rate reviews using a future test year, among other things.

In April 2025, the MoPSC issued an order in Ameren Missouri’s 2024 electric service regulatory rate review, approving nonunanimous stipulations and agreements. The order 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 May 2025, Ameren Missouri filed a request with the MoPSC to modify its existing large primary service tariff to require customers requesting 100 MW or more of demand and who are served at transmission level voltage to comply with additional tariff terms. The additional terms include a minimum service term of 15 years, minimum demand charges of 70% 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 allows customers to support renewable generation, battery storage, 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, with a decision by the MoPSC expected 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 July 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 July 2025, the ICC staff submitted its calculation of the reconciliation adjustment, recommending recovery of $49 million. The ICC staff’s

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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. In July 2025, the ICC staff recommended an increase to annual revenues for natural gas delivery service of $103 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 July 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. A decision by the ICC in this proceeding is required by early December 2025, with new rates expected to be effective in December 2025.

In February 2025, Ameren Illinois filed an energy-efficiency plan with the ICC, which includes annual investments in electric energy-efficiency programs up to $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. A decision by the ICC in this proceeding is expected by September 2025.

In May 2025, Ameren Illinois filed its annual electric energy-efficiency formula rate update to increase its rates by $12 million with the ICC. An ICC decision in this proceeding is required by December 2025, with new rates effective in January 2026.

In October 2024, the FERC issued an order, which decreased the allowed base ROE for FERC-regulated transmission rate base under the MISO tariff 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 November 2024, the MISO transmission owners, including Ameren Missouri, Ameren Illinois, and ATXI, filed a request for rehearing with the FERC, arguing, among other things, the FERC should not have ordered refunds back to September 2016 or imposed interest on those refunds. Also in November 2024, another intervenor filed a request for rehearing with the FERC, requesting the FERC change aspects of the ROE methodology used in the October 2024 order and reconsider its decision in a February 2015 complaint case to deny refunds for the period from February 2015 to May 2016. 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. 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.

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.

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Earnings Summary

The following table presents a summary of Ameren’s earnings for the three and six months ended June 30, 2025 and 2024:


	Three Months				Six Months
	2025		2024		2025		2024
Net income attributable to Ameren common shareholders	$	275	$	258	$	564	$	519
Earnings per common share – diluted	1.01		0.97		2.08		1.95

Net income attributable to Ameren common shareholders increased $17 million and earnings per diluted share increased 4 cents in the three months ended June 30, 2025, compared with the year-ago period. The increase was due to net income increases of $22 million, $7 million, $4 million, and $3 million at Ameren Missouri, Ameren Transmission, Ameren Illinois Natural Gas, and Ameren Illinois Electric Distribution, respectively. These increases were partially offset by an increase in net loss of $16 million for activity not reported as part of a segment, primarily at Ameren (parent).

Net income attributable to Ameren common shareholders increased $45 million and earnings per diluted share increased 13 cents in the six months ended June 30, 2025, compared with the year-ago period. The increase was due to net income increases of $39 million, $24 million, $10 million, and $6 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 $31 million for activity not reported as part of a segment, primarily at Ameren (parent).

Earnings per diluted share were favorably affected in the three and six months ended June 30, 2025, compared to the year-ago periods (except where a specific period is referenced), by:

•decreased interest charges resulting from higher deferrals related to infrastructure investments associated with the PISA and RESRAM and increased base rate revenues for the inclusion of previously deferred interest charges pursuant to the April 2025 MoPSC electric rate order (4 cents and 9 cents per share, respectively);

•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 (8 cents per share for both periods);

•increased rate base investments at Ameren Transmission and Ameren Illinois Electric Distribution (2 cents and 6 cents per share, respectively);

•a higher allowance for equity funds used during construction at Ameren Transmission, primarily resulting from a decreased level of short-term borrowings included in the calculation and higher average construction work in progress balances (3 cents and 5 cents per share, respectively);

•decreased other operations and maintenance expenses not subject to formula rates, riders, or trackers, excluding the effects of storm expenses, primarily due to the absence in 2025 of a charge at Ameren Missouri related to the NSR and Clean Air Act litigation associated with the Rush Island Energy Center (4 cents per share in the six months ended June 30, 2025); and

•increased retail electric sales volumes at Ameren Missouri, excluding customer energy-efficiency programs, primarily due to colder winter temperatures in 2025 compared to the prior-year period (estimated at 2 cents per share for the six months ended June 30, 2025).

Earnings per diluted share were unfavorably affected in the three and six months ended June 30, 2025, compared to the year-ago periods (except where a specific period is referenced), by:

•increased financing costs primarily due to higher short-term and long-term debt balances at Ameren (parent), and higher interest rates on higher debt balances at Ameren Missouri (6 cents and 14 cents per share, respectively);

•decreased retail electric sales volumes at Ameren Missouri, excluding customer energy-efficiency programs, primarily due to milder spring and early summer temperatures in 2025 compared to the prior-year period (estimated at 4 cents per share for the three months ended June 30, 2025); and

•increased weighted-average basic common shares outstanding resulting from issuances of common shares (2 cents and 3 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 six months ended June 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

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Expenses; Depreciation and Amortization Expenses; Taxes Other Than Income Taxes; Other Income, Net; Interest Charges; and Income Taxes, see the major headings below.

Below is Ameren’s table of income statement components by segment for the three and six months ended June 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	$	1,315	$	573	$	—	$	208	$	(58)	$	2,038
Natural gas revenues	25		—		158		—		—		183
Fuel and purchased power	(614)		(223)		—		—		43		(794)
Natural gas purchased for resale	(9)		—		(30)		—		—		(39)
Other operations and maintenance expenses	(238)		(156)		(55)		(18)		7		(460)
Depreciation and amortization expenses	(209)		(93)		(33)		(49)		(2)		(386)
Taxes other than income taxes	(89)		(20)		(16)		(3)		(3)		(131)
Operating income (loss)	181		81		24		138		(13)		411
Other income, net	47		23		5		10		11		96
Interest charges	(70)		(26)		(16)		(29)		(46)		(187)
Income (taxes) benefit	(7)		(13)		(3)		(33)		13		(43)
Net income (loss)	151		65		10		86		(35)		277
Noncontrolling interests – preferred stock dividends	(1)		(1)		—		—		—		(2)
Net income (loss) attributable to Ameren common shareholders	$	150	$	64	$	10	$	86	$	(35)	$	275
Three Months 2024:
Electric revenues	$	864	$	509	$	—	$	191	$	(43)	$	1,521
Natural gas revenues	24		—		148		—		—		172
Fuel and purchased power	(189)		(168)		—		—		30		(327)
Natural gas purchased for resale	(9)		—		(24)		—		—		(33)
Other operations and maintenance expenses	(247)		(153)		(59)		(16)		10		(465)
Depreciation and amortization expenses	(208)		(93)		(33)		(40)		(2)		(376)
Taxes other than income taxes	(91)		(19)		(15)		(2)		(4)		(131)
Operating income (loss)	144		76		17		133		(9)		361
Other income, net	49		27		7		4		16		103
Interest charges	(63)		(26)		(15)		(29)		(32)		(165)
Income (taxes) benefit	(1)		(15)		(3)		(29)		9		(39)
Net income (loss)	129		62		6		79		(16)		260
Noncontrolling interests – preferred stock dividends	(1)		(1)		—		—		—		(2)
Net income (loss) attributable to Ameren common shareholders	$	128	$	61	$	6	$	79	$	(16)	$	258

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	Ameren Missouri		Ameren Illinois Electric Distribution		Ameren Illinois Natural Gas		Ameren Transmission		Other / Intersegment Eliminations		Ameren
Six Months 2025:
Electric revenues	$	2,208	$	1,145	$	—	$	418	$	(111)	$	3,660
Natural gas revenues	89		—		569		—		—		658
Fuel and purchased power	(944)		(435)		—		—		83		(1,296)
Natural gas purchased for resale	(39)		—		(169)		—		—		(208)
Other operations and maintenance expenses	(488)		(322)		(110)		(37)		12		(945)
Depreciation and amortization expenses	(403)		(184)		(65)		(97)		(4)		(753)
Taxes other than income taxes	(178)		(41)		(45)		(4)		(7)		(275)
Operating income (loss)	245		163		180		280		(27)		841
Other income, net	90		46		10		17		18		181
Interest charges	(130)		(52)		(31)		(58)		(91)		(362)
Income (taxes) benefit	(11)		(29)		(41)		(64)		52		(93)
Net income (loss)	194		128		118		175		(48)		567
Noncontrolling interests – preferred stock dividends	(2)		(1)		—		—		—		(3)
Net income (loss) attributable to Ameren common shareholders	$	192	$	127	$	118	$	175	$	(48)	$	564
Six Months 2024:
Electric revenues	$	1,578	$	1,015	$	—	$	376	$	(84)	$	2,885
Natural gas revenues	85		—		539		—		—		624
Fuel and purchased power	(355)		(360)		—		—		60		(655)
Natural gas purchased for resale	(37)		—		(147)		—		—		(184)
Other operations and maintenance expenses	(501)		(289)		(117)		(35)		7		(935)
Depreciation and amortization expenses	(403)		(186)		(66)		(79)		(3)		(737)
Taxes other than income taxes	(178)		(36)		(41)		(4)		(7)		(266)
Operating income (loss)	189		144		168		258		(27)		732
Other income, net	93		49		14		6		30		192
Interest charges	(125)		(48)		(30)		(58)		(58)		(319)
Income (taxes) benefit	(2)		(27)		(40)		(55)		41		(83)
Net income (loss)	155		118		112		151		(14)		522
Noncontrolling interests – preferred stock dividends	(2)		(1)		—		—		—		(3)
Net income (loss) attributable to Ameren common shareholders	$	153	$	117	$	112	$	151	$	(14)	$	519

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Below is Ameren Illinois’ table of income statement components by segment for the three and six months ended June 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	$	573	$	—	$	152	$	(40)	$	685
Natural gas revenues	—		158		—		—		158
Purchased power	(223)		—		—		40		(183)
Natural gas purchased for resale	—		(30)		—		—		(30)
Other operations and maintenance expenses	(156)		(55)		(14)		—		(225)
Depreciation and amortization expenses	(93)		(33)		(37)		—		(163)
Taxes other than income taxes	(20)		(16)		(1)		—		(37)
Operating income	81		24		100		—		205
Other income, net	23		5		9		—		37
Interest charges	(26)		(16)		(21)		—		(63)
Income taxes	(13)		(3)		(25)		—		(41)
Net income	65		10		63		—		138
Preferred stock dividends	(1)		—		—		—		(1)
Net income attributable to common shareholder	$	64	$	10	$	63	$	—	$	137
Three Months 2024:
Electric revenues	$	509	$	—	$	136	$	(27)	$	618
Natural gas revenues	—		148		—		—		148
Purchased power	(168)		—		—		27		(141)
Natural gas purchased for resale	—		(24)		—		—		(24)
Other operations and maintenance expenses	(153)		(59)		(12)		—		(224)
Depreciation and amortization expenses	(93)		(33)		(28)		—		(154)
Taxes other than income taxes	(19)		(15)		(1)		—		(35)
Operating income	76		17		95		—		188
Other income, net	27		7		3		—		37
Interest charges	(26)		(15)		(19)		—		(60)
Income taxes	(15)		(3)		(22)		—		(40)
Net income	62		6		57		—		125
Preferred stock dividends	(1)		—		—		—		(1)
Net income attributable to common shareholder	$	61	$	6	$	57	$	—	$	124
Six Months 2025:
Electric revenues	$	1,145	$	—	$	306	$	(77)	$	1,374
Natural gas revenues	—		569		—		—		569
Purchased power	(435)		—		—		77		(358)
Natural gas purchased for resale	—		(169)		—		—		(169)
Other operations and maintenance expenses	(322)		(110)		(29)		—		(461)
Depreciation and amortization expenses	(184)		(65)		(73)		—		(322)
Taxes other than income taxes	(41)		(45)		(2)		—		(88)
Operating income	163		180		202		—		545
Other income, net	46		10		15		—		71
Interest charges	(52)		(31)		(42)		—		(125)
Income taxes	(29)		(41)		(47)		—		(117)
Net income	128		118		128		—		374
Preferred stock dividends	(1)		—		—		—		(1)
Net income attributable to common shareholder	$	127	$	118	$	128	$	—	$	373

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	Ameren Illinois Electric Distribution		Ameren Illinois Natural Gas		Ameren Illinois Transmission		Other / Intersegment Eliminations		Ameren Illinois
Six Months 2024:
Electric revenues	$	1,015	$	—	$	267	$	(55)	$	1,227
Natural gas revenues	—		539		—		—		539
Purchased power	(360)		—		—		55		(305)
Natural gas purchased for resale	—		(147)		—		—		(147)
Other operations and maintenance expenses	(289)		(117)		(28)		—		(434)
Depreciation and amortization expenses	(186)		(66)		(55)		—		(307)
Taxes other than income taxes	(36)		(41)		(2)		—		(79)
Operating income	144		168		182		—		494
Other income, net	49		14		5		—		68
Interest charges	(48)		(30)		(37)		—		(115)
Income taxes	(27)		(40)		(40)		—		(107)
Net income	118		112		110		—		340
Preferred stock dividends	(1)		—		—		—		(1)
Net income attributable to common shareholder	$	117	$	112	$	110	$	—	$	339

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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 six months ended June 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)	$	44	$	9	$	—	$	17	$	—	$	70
Effect of weather (estimate)(c)	(27)		—		—		—		—		(27)
Retail sales volumes and changes in customer usage patterns (excluding the estimated effects of weather and MEEIA)	13		—		—		—		—		13
Transmission service charges (not included in the FAC)	1		—		—		—		—		1

Off-system sales, capacity, transmission, and FAC revenues, net	435		—		—		—		—		435
Ameren Illinois energy-efficiency program investment revenues	—		(1)		—		—		—		(1)

Rush Island Energy Center base rate revenue deferral	(9)		—		—		—		—		(9)
Securitized utility tariff bond surcharges	11		—		—		—		—		11
RESRAM(d)	(9)		—		—		—		—		(9)
Other	2		4		—		—		(2)		4
Cost recovery mechanisms – offset in fuel and purchased power(e)	(6)		55		—		—		(13)		36
Other cost recovery mechanisms(f)	(4)		(3)		—		—		—		(7)
Total electric revenue change	$	451	$	64	$	—	$	17	$	(15)	$	517
Natural gas revenue change:


Effect of weather (estimate)(c)	2		—		—		—		—		2


VBA	—		—		6		—		—		6
Other	—		—		(2)		—		—		(2)
Cost recovery mechanisms – offset in natural gas purchased for resale(e)	(1)		—		6		—		—		5

Total natural gas revenue change	$	1	$	—	$	10	$	—	$	—	$	11

Six Months
Electric revenue change:
Base rates (estimate)(b)	$	44	$	31	$	—	$	42	$	—	$	117
Effect of weather (estimate)(c)	11		—		—		—		—		11

Transmission service charges (not included in the FAC)	2		—		—		—		—		2

Off-system sales, capacity, and FAC revenues, net	599		—		—		—		—		599
Ameren Illinois energy-efficiency program investment revenues	—		4		—		—		—		4

Rush Island Energy Center base rate revenue deferral	(26)		—		—		—		—		(26)
Securitized utility tariff bond surcharges	24		—		—		—		—		24
RESRAM(d)	(7)		—		—		—		—		(7)
Other	4		9		—		—		(4)		9
Cost recovery mechanisms – offset in fuel and purchased power(e)	(18)		75		—		—		(23)		34
Other cost recovery mechanisms(f)	(3)		11		—		—		—		8
Total electric revenue change	$	630	$	130	$	—	$	42	$	(27)	$	775
Natural gas revenue change:


Effect of weather (estimate)(c)	9		—		—		—		—		9


VBA	—		—		6		—		—		6
Other	—		—		1		—		—		1
Cost recovery mechanisms – offset in natural gas purchased for resale(e)	(5)		—		22		—		—		17
Other cost recovery mechanisms(f)	—		—		1		—		—		1
Total natural gas revenue change	$	4	$	—	$	30	$	—	$	—	$	34

(a)Includes an increase in transmission revenues of $16 million and $39 million at Ameren Illinois for the three and six months ended June 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.

(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.

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(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 six months ended June 30, 2025, activity in Other/Intersegment Eliminations of $13 million and $23 million, respectively, was due primarily to the changes in Ameren Transmission revenue from transmission services provided to Ameren Illinois Electric Distribution (-$13 million and -$22 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 $517 million, or 34%, and $775 million, or 27%, for the three and six months ended June 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

Ameren Transmission’s electric revenues increased $17 million, or 9%, and $42 million, or 11%, for the three and six months ended June 30, 2025, respectively, compared with the year-ago periods. Revenues were primarily affected by higher recoverable expenses (+$12 million and +$32 million, respectively) and increased capital investment (+$5 million and +$10 million, respectively), as evidenced by a 6% increase in rate base used to calculate the revenue requirement.

Ameren Missouri

Ameren Missouri’s electric revenues increased $451 million, or 52%, and $630 million, or 40%, for the three and six months ended June 30, 2025, respectively, compared with the year-ago periods.

The following items increased Ameren Missouri’s electric revenues for the three and six months ended June 30, 2025 (except where a specific period is referenced):

•“Off-system sales, capacity, transmission, and FAC revenues, net” increased $435 million and $599 million, respectively, primarily due to higher spring and summer capacity prices, which were set by annual MISO auctions. See Outlook for additional information related to the April 2024 and April 2025 MISO auctions.

•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 $44 million for the three and six months ended June 30, 2025. 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.

•Revenues increased $11 million and $24 million, respectively, due to the collection of 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 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 $13 million for the three months ended June 30, 2025, primarily due to increased commercial and residential retail sales volumes and higher realized prices related to changes in customer usage patterns.

•The effect of weather increased revenues an estimated $11 million for the six months ended June 30, 2025 due to colder winter temperatures as heating degree days increased 22%, partially offset by milder spring and early summer temperatures as cooling degree days decreased 26% from the year-ago period.

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The following items decreased Ameren Missouri’s electric revenues for the three and six months ended June 30, 2025 (except where a specific period is referenced):

•The effect of weather decreased revenues an estimated $27 million for the three months ended June 30, 2025, due to milder spring and early summer temperatures in 2025 as cooling degree days decreased 27% from the year-ago period.

•In accordance with the June 2024 MoPSC financing order, revenues decreased $9 million and $26 million, respectively, 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 $6 million and $18 million, respectively, 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 $9 million and $7 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 $67 million, or 11%, and $147 million, or 12%, for the three and six months ended June 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 $64 million, or 13%, and $130 million, or 13%, for the three and six months ended June 30, 2025, respectively, compared with the year-ago periods.

The following items increased Ameren Illinois Electric Distribution’s revenues for the three and six months ended June 30, 2025 (except where a specific period is referenced):

•Revenues associated with “Cost recovery mechanisms – offset in fuel and purchased power” increased $55 million and $75 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 $9 million and $31 million, respectively, due to higher recoverable non-purchased power expenses

(+$5 million and +$25 million, respectively) and increased capital investment (+$4 million and +$6 million, respectively).

•Other cost recovery mechanisms increased revenues by $11 million for the six months ended June 30, 2025, primarily due to a higher amount of bad debt costs included in customer rates pursuant to the associated rider.

•Other revenues increased $4 million and $9 million, respectively, primarily due to mutual assistance provided to Ameren Missouri for major storms experienced in 2025 throughout its service territory and increased revenues related to pole rents.

•Revenues increased $4 million for the six months ended June 30, 2025, 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 $3 million for the three months ended June 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 $16 million, or 12%, and $39 million, or 15%, for the three and six months ended June 30, 2025, respectively, compared with the year-ago periods. Base rate revenues were primarily affected by higher recoverable expenses (+$12 million and +$31 million, respectively) and increased capital investment (+$4 million and +$8 million, respectively), as evidenced by a 7% increase in rate base used to calculate the revenue requirement.

Natural Gas Revenues

Ameren

Ameren’s natural gas revenues increased $11 million, or 6%, and $34 million, or 5%, for the three and six months ended June 30, 2025, respectively, compared with the year-ago periods, due to increased revenues at Ameren Illinois Natural Gas and Ameren Missouri, as discussed below.

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Ameren Missouri

Ameren Missouri’s natural gas revenues were comparable for the three months ended June 30, 2025, and increased $4 million, or 5%, compared with the six months ended June 30, 2025, primarily due to colder winter temperatures.

Ameren Illinois Natural Gas

Ameren Illinois Natural Gas’ revenues increased $10 million, or 7%, and $30 million, or 6%, for the three and six months ended June 30, 2025, respectively, compared with the year-ago periods. “Cost recovery mechanisms – offset in natural gas purchased for resale” increased revenues $6 million and $22 million for the three and six months ended June 30, 2025, respectively, due to a higher collection of natural gas costs previously deferred under the PGA. The increase in natural gas revenues under the PGA are fully offset by an increase in natural gas purchased for resale expenses. Revenues increased $6 million for the three and six months ended June 30, 2025, related 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 six months ended June 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)	$	437	$	—	$	—	$	—	$	—	$	437

Effect of weather (estimate)(a)	(4)		—		—		—		—		(4)

Transmission service charges (not included in the FAC)	2		—		—		—		—		2

Other	(4)		—		—		—		—		(4)
Cost recovery mechanisms – offset in electric revenue(b)	(6)		55		—		—		(13)		36
Total fuel and purchased power change	$	425	$	55	$	—	$	—	$	(13)	$	467
Six Months
Fuel and purchased power change:
Energy costs (excluding the estimated effect of weather)	$	602	$	—	$	—	$	—	$	—	$	602

Effect of weather (estimate)(a)	4		—		—		—		—		4
Transmission service charges (not included in the FAC)	5		—		—		—		—		5

Other	(4)		—		—		—		—		(4)
Cost recovery mechanisms – offset in electric revenue(b)	(18)		75		—		—		(23)		34
Total fuel and purchased power change	$	589	$	75	$	—	$	—	$	(23)	$	641

(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 six months ended June 30, 2025, activity in Other/Intersegment Eliminations of $13 million and $23 million, respectively, was due primarily to the changes in Ameren Transmission revenue from transmission services provided to Ameren Illinois Electric Distribution (-$13 million and -$22 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 $467 million, or 143%, and $641 million, or 98%, for the three and six months ended June 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 $425 million, or 225%, and $589 million, or 166%, for the three and six months ended June 30, 2025, compared with the year-ago periods.

The following items increased Ameren Missouri’s fuel and purchased power expense for the three and six months ended June 30, 2025, compared with the year-ago periods (except where a specific period is referenced):

•Energy costs increased $437 million and $602 million, respectively, primarily due to higher spring and summer capacity prices that were set by annual MISO auctions. See Outlook for additional information related to the April 2024 and April 2025 MISO auctions. Ameren Missouri’s 5% exposure to net energy cost variances under the FAC 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)”. These results had an immaterial impact on earnings between periods.

•Transmission service charges (not included in the FAC) increased $2 million and $5 million, respectively, due to higher transmission rates related to increased revenue requirements of other MISO transmission operators.

•Fuel and purchased power expenses increased an estimated $4 million for the six months ended June 30, 2025, due to an increase in electric retail sales as a result of colder winter temperatures.

The following items decreased Ameren Missouri’s fuel and purchased power expense for the three and six months ended June 30, 2025, compared with the year-ago periods (except where a specific period is referenced):

•“Cost recovery mechanisms — offset in electric revenue” decreased $6 million and $18 million, respectively, 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.

•Fuel and purchased power expenses decreased an estimated $4 million for the three months ended June 30, 2025 due to a decrease in electric retail sales as a result of milder spring and early summer temperatures.

Ameren Illinois Electric Distribution

Ameren Illinois Electric Distribution’s purchased power expenses increased $55 million, or 33%, and $75 million, or 21%, for the three and six months ended June 30, 2025, respectively, compared with the year-ago periods, primarily due to higher summer capacity prices that were set by annual MISO auctions (+$43 million and +$41 million, respectively). See Outlook for additional information related to the April 2024 and April 2025 MISO auctions. In addition to higher capacity prices, increases in transmission service charges (+$15 million and

+$26 million, respectively), volumes (+$7 million and +$23 million, respectively), primarily due to residential and small commercial customers switching from alternative retail electric suppliers to Ameren Illinois’ supplied power, and other power riders (+$5 million in both periods) increased purchased power expenses for the three and six months ended June 30, 2025. Decreased energy prices (-$15 million and

-$20 million, respectively), which largely reflect the results of IPA procurement events for Ameren Illinois' supplied power, partially offset the increases in purchased power for both periods. 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 six months ended June 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:
Effect of weather (estimate)(a)	$	1	$	—	$	—	$	—	$	—	$	1
Cost recovery mechanisms – offset in natural gas revenue(b)	(1)		—		6		—		—		5
Total natural gas purchased for resale change	$	—	$	—	$	6	$	—	$	—	$	6
Six Months
Natural gas purchased for resale change:
Effect of weather (estimate)(a)	$	7	$	—	$	—	$	—	$	—	$	7
Cost recovery mechanisms – offset in natural gas revenue(b)	(5)		—		22		—		—		17
Total natural gas purchased for resale change	$	2	$	—	$	22	$	—	$	—	$	24

(a)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.

(b)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.

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 increased $6 million, or 18%, and $24 million, or 13%, for the three and six months ended June 30, 2025, respectively, compared with the year-ago periods, due primarily 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 six months ended June 30, 2025, compared with the year-ago periods. Colder winter temperatures increased natural gas costs $7 million for the six months ended June 30, 2025 as heating degree days increased 22%, while “Cost recovery mechanisms — offset in natural gas revenue” decreased natural gas costs $5 million due to lower amortization of natural gas costs that were previously deferred under the PGA for the six months ended June 30, 2025.

Ameren Illinois Natural Gas

Ameren Illinois Natural Gas’ natural gas purchased for resale expenses increased $6 million, or 25%, and $22 million, or 15%, for the three and six months ended June 30, 2025, respectively, compared with the year-ago periods, primarily due to higher 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 $5 Million (QTD YoY)

Overall Ameren Increase of $10 Million (YTD YoY)

Total by Segment(a)

(a)Includes $18 million and $16 million at Ameren Transmission in the three months ended June 30, 2025 and 2024, respectively. Includes other/intersegment eliminations of $(7) million and $(10) million in the three months ended June 30, 2025 and 2024, respectively. Also includes other/intersegment eliminations of $(12) million and $(7) million in the six months ended June 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 $5 million in the three months ended June 30, 2025, and increased $10 million in the six months ended June 30, 2025, due to the changes discussed below. In addition to changes by segments discussed below, other operations and maintenance expenses increased $3 million in the three months ended June 30, 2025 and decreased $5 million in the six months ended June 30, 2025 for activity not reported as part of a segment, as reflected in “Other/Intersegment Eliminations” above. This is primarily due to a decrease of $5 million in individually insignificant items in the six months ended June 30, 2025 and a decrease of $5 million and $8 million in the elimination of the non-service cost component of net periodic benefit income in the three and six months ended June 30, 2025, respectively. 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 $8 million that occurred in 2024 for the three and six months ended June 30, 2025.

Ameren Transmission

Other operations and maintenance expenses were comparable between periods.

Ameren Missouri

Other operations and maintenance expenses decreased $9 million and $13 million in the three and six months ended June 30, 2025, respectively, compared with the year-ago periods. The following items decreased other operations and maintenance expenses in the three and six months ended June 30, 2025, compared with the year-ago periods (except where a specific period is referenced):

•The absence in 2025 of a $15 million charge in the six months ended June 30, 2025, related to the NSR and Clean Air Act litigation associated with the Rush Island Energy Center.

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•Expenses associated with the MEEIA customer energy-efficiency program decreased $6 million and $7 million, respectively, as approved by the MoPSC.

•Callaway Energy Center operating costs decreased $5 million in both periods, primarily due to the spring 2025 refueling and maintenance outage.

The following items partially offset the decrease in other operations and maintenance expenses for the three and six months ended June 30, 2025, compared with the year-ago periods (except where a specific period is referenced):

•Transmission and distribution storm-related expenses increased $4 million and $9 million, respectively, because of the major storms experienced throughout its service territory in 2025.

•Increased expense of $4 million for cloud-related software in the six months ended June 30, 2025.

•Non-nuclear energy center maintenance increased $4 million in the six months ended June 30, 2025, primarily due to an increase in coal additives.

Ameren Illinois

Other operations and maintenance expenses increased $1 million and $27 million in the three and six months ended June 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 $3 million and $33 million in the three and six months ended June 30, 2025, respectively, primarily due to the following items (except where a specific period is referenced):

•Bad debt costs increased $4 million and $17 million, respectively, 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 $2 million and $6 million, respectively, primarily due to amortization of regulatory assets.

•Storm-related expenses, including related amortizations of previously deferred amounts, increased $3 million and $5 million, respectively, in 2025 due to major storms experienced throughout its service territory in 2025.

•Distribution expenditures increased $4 million in both periods, primarily due to higher levels of pole inspections and other maintenance activity.

The above increases in the three and six months ended June 30, 2025, compared with the year-ago periods, were partially offset by the following items (except where a specific period is referenced):

•Amortization of previous deferrals associated with bad debt costs on purchased receivables decreased $6 million in both periods, 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 $4 million in both periods.

Ameren Illinois Natural Gas

Other operations and maintenance costs decreased $4 million and $7 million in the three and six months ended June 30, 2025, respectively, primarily due to a decrease of $1 million and $4 million, respectively, in labor expense resulting from steps taken to align operations and maintenance expense as a result of the November 2023 ICC natural gas rate order. Additionally, expenses decreased by $3 million in both periods due to a decrease in energy efficiency rider costs.

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 $10 Million (QTD YoY)

Overall Ameren Increase of $16 Million (YTD YoY)

Total by Segment(a)

(a)Includes other/intersegment eliminations of $2 million and $2 million in the three months ended June 30, 2025 and 2024, respectively. Also includes other/intersegment eliminations of $4 million and $3 million in the six months ended June 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 $10 million, $9 million, and $1 million in the three months ended June 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. Depreciation and amortization expenses increased $18 million and $16 million in the six months ended June 30, 2025, compared with the year-ago period at Ameren Transmission and Ameren, respectively, primarily because of additional property, plant, and equipment investments. Ameren’s and Ameren Missouri’s depreciation and amortization expenses for the three and six months ended June 30, 2025, compared with the year-ago periods, were affected by the following, which include the effect of the additional investments at Ameren Missouri:

•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 $11 million, respectively.

•Increased depreciation and amortization of $5 million in both periods 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.

•Higher depreciation not recoverable under PISA or RESRAM increased expenses by $2 million and $4 million, respectively.

•The lower net deferral pursuant to a tracker related to certain excess deferred income taxes, which increased depreciation and amortization expenses by $2 million in both periods.

•The absence of depreciation expense associated with Ameren Missouri’s Rush Island Energy Center decreased expenses by $9 million and $18 million, respectively.

•Lower amortization of prior deferrals and the lower net under-recovery of RESRAM eligible expenses decreased depreciation and amortization expenses by $8 million and $6 million, respectively.

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Taxes Other Than Income Taxes

Increase (Decrease) by Segment

Overall Ameren Change of $— Million (QTD YoY)

Overall Ameren Increase of $9 Million (YTD YoY)

Total by Segment(a)

(a)Includes $3 million, $2 million, $4 million, and $4 million at Ameren Transmission in the three months ended June 30, 2025 and 2024, and in the six months ended June 30, 2025 and 2024, respectively. Also includes other/intersegment eliminations of $3 million, $4 million, $7 million, and $7 million in the three months ended June 30, 2025 and 2024, and in the six months ended June 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 were comparable between periods in the three months ended June 30, 2025 and increased $9 million in the six months ended June 30, 2025, compared with the year-ago period, primarily because of an increase of $5 million and $4 million at 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 $5 million, $4 million and $3 million at Ameren Missouri, Ameren Illinois Natural Gas and Ameren Illinois Electric Distribution, respectively, resulting from increased retail natural gas and electric sales. The above increases were offset primarily by $6 million from a property tax refund at Ameren Missouri.

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Other Income, Net

Increase (Decrease) by Segment

Overall Ameren Decrease of $7 Million (QTD YoY)

Overall Ameren Decrease of $11 Million (YTD YoY)

Total by Segment(a)

(a)Includes $10 million and $4 million at Ameren Transmission in the three months ended June 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 $7 million and $11 million in the three and six months ended June 30, 2025, respectively, compared with the year-ago periods. In addition to changes discussed below, other income, net, decreased $5 million and $12 million, respectively, for activity not reported as part of a segment, primarily due to a decrease of $5 million and $9 million, respectively, in the non-service cost component of net periodic benefit income.

Ameren Transmission

Other income, net, increased $6 million and $11 million in the three and six months ended June 30, 2025, respectively, compared with the year-ago periods, due to a higher 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.

Ameren Missouri

Other income, net, decreased $2 million and $3 million in the three and six months ended June 30, 2025, respectively, compared with the year-ago periods, primarily due to the non-service cost component of net periodic benefit income.

Ameren Illinois

Other income, net, were comparable between periods in the three months ended June 30, 2025 and increased $3 million in the six months ended June 30, 2025, compared with the year-ago period, primarily due to an increase of $13 million in the allowance of equity funds used during construction, primarily at Ameren Illinois Transmission. Other income, net, increased $2 million from other interest income on regulatory balances, largely at Ameren Illinois Electric Distribution. These increases were partially offset by a decrease of $13 million in the non-service cost component of net periodic benefit income, largely at Ameren Illinois Electric Distribution.

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Interest Charges

Increase by Segment

Overall Ameren Increase of $22 Million (QTD YoY)

Overall Ameren Increase of $43 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 $22 million and $43 million in the three and six months ended June 30, 2025, respectively, compared with the year-ago periods. In addition to changes by segments discussed below, interest charges increased $14 million and $33 million respectively, at Ameren (parent), because of increased levels of short-term borrowings that increased interest charges by $6 million and $26 million, respectively. Additionally, interest charges increased $7 million in the three and six months ended June 30, 2025, 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.

Ameren Missouri

Interest charges increased $7 million and $5 million in the three and six months ended June 30, 2025, respectively, compared with the year-ago periods. Interest charges increased by $12 million and $20 million, respectively, primarily due to the issuances of long-term debt in April 2024, October 2024, and April 2025. Additionally, interest charges increased by $6 million and $12 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.

The above increases were 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 $10 million and $27 million, respectively.

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Ameren Illinois

Interest charges increased $3 million and $10 million in the three and six months ended June 30, 2025, respectively, compared with the year-ago periods, primarily due to the following:

Ameren Illinois Transmission

Interest charges increased by $2 million and $5 million, respectively, primarily due to increased interest charges associated with long-term debt of $4 million and $8 million, respectively. The increases were primarily offset by decreased levels of interest charges associated with short-term debt of $2 million and $4 million, respectively.

Ameren Illinois Electric Distribution

Interest charges were comparable in the three months ended June 30, 2025, and increased by $4 million in the six months ended June 30, 2025, primarily because of issuances of long-term debt in June 2024 and March 2025. The increase was offset by decreased levels of borrowing on short-term debt.

Ameren Illinois Natural Gas

Interest charges were comparable between periods.

Income Taxes

The following table presents effective income tax rates for the three and six months ended June 30, 2025 and 2024:


	Three Months(a)				Six Months(a)
	2025		2024		2025		2024
Ameren	13	%	13	%	14	%	14	%
Ameren Missouri	5	%	1	%	6	%	2	%
Ameren Illinois	23	%	24	%	24	%	24	%
Ameren Illinois Electric Distribution	16	%	20	%	18	%	18	%
Ameren Illinois Natural Gas	26	%	35	%	26	%	27	%
Ameren Illinois Transmission	28	%	27	%	27	%	26	%
Ameren Transmission	28	%	27	%	27	%	27	%

(a)Estimate of the annual effective income tax rate adjusted to reflect the tax effect of items discrete to the three and six months ended June 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.

The effective tax rate was lower at Ameren Illinois Electric Distribution and Ameren Illinois Natural Gas in the three months ended June 30, 2025, compared with the year-ago period, primarily because of the timing of pre-tax income and higher tax benefits related to the allowance for funds used during construction.

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 June 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, environmental compliance, 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

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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 six months ended June 30, 2025. As of June 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. As of June 30, 2025, Ameren had approximately $230 million of common stock available for sale under the ATM program, which takes into account the forward sale agreements in effect as of June 30, 2025. In 2025, Ameren intends to increase the amount of common stock available for sale under its 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 six months ended June 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	$	1,293	(a)	$	1,049	(a)	$	244	$	(2,111)	$	(1,932)	$	(179)	$	884	$	912	$	(28)

1,400







1,422

(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 six months ended June 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 six months ended June 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



Total Ameren long-term debt issuances		$	1,599		$	1,470
Issuances of Common Stock
Ameren:
DRPlus and 401(k)(a)(b)	Various	$	25		$	21


Total Ameren common stock issuances(c)		$	25		$	21

Maturities of Long-term Debt


Ameren Missouri:

3.50% Senior secured notes due 2024	April	$	—		$	350
Ameren Illinois:
3.25% Senior secured notes due 2025	March	300			—



Total Ameren long-term debt maturities		$	300	(d)	$	350

Material Contracts10.1Ameren

Forward Sale Agreement, dated May 12, 2025, between Ameren and Goldman Sachs & Co. LLC, as a Forward Purchaser

May 12, 2025 Form 8-K, Exhibit 10.1, File No. 1-1475610.2Ameren

Forward Sale Agreement, dated May 12, 2025, between Ameren and JPMorgan Chase Bank, National Association, as a Forward Purchaser

May 12, 2025 Form 8-K, Exhibit 10.2, File No. 1-1475610.3Ameren

Forward Sale Agreement, dated May 12, 2025, between Ameren and Barclays Bank PLC, as a Forward Purchaser

May 12, 2025 Form 8-K, Exhibit 10.3, File No. 1-1475610.4Ameren

Forward Sale Agreement, dated May 12, 2025, between Ameren and Wells Fargo Bank, National Association, as a Forward Purchaser

May 12, 2025 Form 8-K, Exhibit 10.4, File No. 1-1475610.5Ameren

Additional Forward Sale Agreement, dated May 13, 2025, between Ameren and Goldman Sachs & Co. LLC, as a Forward Purchaser

May 12, 2025 Form 8-K, Exhibit 10.5, File No. 1-1475610.6Ameren

Additional Forward Sale Agreement, dated May 13, 2025, between Ameren and JPMorgan Chase Bank, National Association, as a Forward Purchaser

May 12, 2025 Form 8-K, Exhibit 10.6, File No. 1-1475610.7Ameren

Additional Forward Sale Agreement, dated May 13, 2025, between Ameren and Barclays Bank PLC, as a Forward Purchaser

May 12, 2025 Form 8-K, Exhibit 10.7, File No. 1-1475610.8Ameren

Additional Forward Sale Agreement, dated May 13, 2025, between Ameren and Wells Fargo Bank, National Association, as a Forward Purchaser

May 12, 2025 Form 8-K, Exhibit 10.8, File No. 1-14756Rule 13a-14(a) / 15d-14(a) Certifications31.1Ameren

Rule 13a-14(a)/15d-14(a) Certification of Principal Executive Officer of Ameren

31.2Ameren

Rule 13a-14(a)/15d-14(a) Certification of Principal Financial Officer of Ameren

31.3Ameren Missouri

Rule 13a-14(a)/15d-14(a) Certification of Principal Executive Officer of Ameren Missouri

31.4Ameren Missouri

Rule 13a-14(a)/15d-14(a) Certification of Principal Financial Officer of Ameren Missouri

31.5Ameren Illinois

Rule 13a-14(a)/15d-14(a) Certification of Principal Executive Officer of Ameren Illinois

31.6Ameren Illinois

Rule 13a-14(a)/15d-14(a) Certification of Principal Financial Officer of Ameren Illinois

Section 1350 Certifications32.1Ameren

Section 1350 Certification of Principal Executive Officer and Principal Financial Officer of Ameren

32.2Ameren Missouri

Section 1350 Certification of Principal Executive Officer and Principal Financial Officer of Ameren Missouri

32.3Ameren Illinois

Section 1350 Certification of Principal Executive Officer and Principal Financial Officer of Ameren Illinois

Interactive Data Files101.INSAmeren CompaniesInline XBRL Instance Document - the instance document does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document101.SCHAmeren CompaniesInline XBRL Taxonomy Extension Schema Document101.CALAmeren CompaniesInline XBRL Taxonomy Extension Calculation Linkbase Document101.LABAmeren CompaniesInline XBRL Taxonomy Extension Label Linkbase Document101.PREAmeren CompaniesInline XBRL Taxonomy Extension Presentation Linkbase Document101.DEFAmeren CompaniesInline XBRL Taxonomy Extension Definition Document104Ameren CompaniesCover 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.

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 Senior Executive Vice President and Chief Financial Officer (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: August 4, 2025

UNION ELECTRIC CO - Quarter Report: 2025 June (Form 10-Q)

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