v3.26.1
Supplemental Information (Tables)
 6 Months Ended
Jun. 30, 2026
Supplemental Information [Abstract]  
Schedule of Cash and Cash Equivalents Including Restricted Cash
The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported within the balance sheets and the statements of cash flows at June 30, 2026, and December 31, 2025:
June 30, 2026December 31, 2025
AmerenAmeren
Missouri		Ameren
Illinois		AmerenAmeren
Missouri		Ameren
Illinois
“Cash and cash equivalents”$12 $— $7 $13 $6 $3 
Restricted cash included in “Other current assets”45 35 6 63 54 5 
Restricted cash included in “Other assets”402 — 402 336 — 336 
Restricted cash included in “Nuclear decommissioning trust fund”11 11 — 8 8 — 
Total cash, cash equivalents, and restricted cash$470 $46 $415 $420 $68 $344 
Schedule of Accounts, Notes, Loans and Financing Receivable
The following table provides a reconciliation of the beginning and ending amount of the allowance for doubtful accounts for the three and six months ended June 30, 2026 and 2025:
Three MonthsSix Months
2026202520262025
Ameren:
Beginning of period$41 $41 $39 $30 
Bad debt expense11 3 21 19 
Charged to other accounts(a)
2 2 3 3 
Net write-offs(9)(7)(18)(13)
End of period$45 $39 $45 $39 
Ameren Missouri:
Beginning of period$15 $12 $17 $12 
Bad debt expense4 2 6 4 
Net write-offs(2)(2)(6)(4)
End of period$17 $12 $17 $12 
Ameren Illinois:(b)
Beginning of period$26 $29 $22 $18 
Bad debt expense7 

1 15 15 
Charged to other accounts(a)
2 2 3 3 
Net write-offs(7)(5)(12)(9)
End of period$28 $27 $28 $27 
(a)Amounts associated with the allowance for doubtful accounts related to receivables purchased by Ameren Illinois from alternative retail electric suppliers, as required by the Illinois Public Utilities Act.
(b)Ameren Illinois has rate-adjustment mechanisms that allow it to recover the difference between its actual net bad debt write-offs under GAAP, including those associated with receivables purchased from alternative retail electric suppliers, and the amount of net bad debt write-offs included in its base rates. The table above does not include the impact related to the riders.
Schedule of Cash Flow, Supplemental Disclosures
The following table provides noncash financing and investing activity excluded from the statements of cash flows for the six months ended June 30, 2026 and 2025:
June 30, 2026June 30, 2025
AmerenAmeren
Missouri		Ameren
Illinois		AmerenAmeren
Missouri		Ameren
Illinois
Investing:
Accrued capital expenditures, including nuclear fuel expenditures$677 
(a)
$468 
(a)
$187 $453 $284 $162 
Net realized and unrealized gain – nuclear decommissioning trust fund93 93 — 57 57 — 
Financing:
Issuance of common stock for stock-based compensation$25 $— $— $25 $— $— 
Issuance of common stock under the DRPlus7 — — 7 — — 
(a)Includes amounts associated with the February 2026 acquisition of the Split Rail Solar Project with payment contingent upon completion of the project. The final Split Rail payment was made in July 2026.
Asset Retirement Obligation Disclosure
The following table provides a reconciliation of the beginning and ending carrying amount of AROs for the six months ended June 30, 2026:
Ameren
Missouri		Ameren
Illinois		Ameren
Balance at December 31, 2025
$849 
(a) 
$5 
(b) 
$854 
(a) 
Liabilities incurred7 — 7 
Liabilities settled(2)(c)(2)
Accretion19 
(d) 
(c)19 
(d) 
Balance at June 30, 2026
$873 
(a) 
$5 
(b) 
$878 
(a) 
(a)Balance included $5 million in “Other current liabilities” on the balance sheet as of both June 30, 2026, and December 31, 2025.
(b)Included in “Other deferred credits and liabilities” on the balance sheet.
(c)Amount less than $1 million.
(d)Accretion expense attributable to Ameren Missouri was recorded as a decrease to regulatory liabilities.
Schedule of excise taxes The following table presents the excise taxes recorded on a gross basis in “Operating Revenues – Electric,” “Operating Revenues – Natural gas” and “Operating Expenses – Taxes other than income taxes” on the statements of income for the three and six months ended June 30, 2026 and 2025:
Three MonthsSix Months
2026202520262025
Ameren Missouri$47 $43 $87 $81 
Ameren Illinois32 31 77 74 
Ameren$79 $74 $164 $155 
Schedule of Earnings Per Share, Basic and Diluted
The following table reconciles the basic weighted-average number of common shares outstanding to the diluted weighted-average number of common shares outstanding for the three and six months ended June 30, 2026 and 2025:
Three MonthsSix Months
2026202520262025
Weighted-average Common Shares Outstanding – Basic276.8 270.3 276.6 270.1 
Assumed settlement of performance share units and restricted stock units0.8 0.8 1.0 0.9 
Dilutive effect of forward sale agreements1.1 0.5 1.0 0.5 
Weighted-average Common Shares Outstanding – Diluted(a)
278.7 271.6 278.6 271.5 
(a)There was an immaterial number of anti-dilutive performance share units excluded from the earnings per diluted share calculations for the three and six months ended June 30, 2026 and 2025. Outstanding forward sale agreements as of June 30, 2026 and 2025 that were anti-dilutive for the three and six months ended June 30, 2026 and 2025 were excluded from the earnings per diluted share calculation as calculated using the treasury stock method. For additional information about the outstanding forward sale agreements, see Note 4 – Long-term Debt and Equity Financings.