| Three Months Ended March 31, | ||||||||||||||
| 2026 | 2025 | |||||||||||||
| Operating Revenues: | ||||||||||||||
| Electric | $ | 1,661 | $ | 1,622 | ||||||||||
| Natural gas | 515 | 475 | ||||||||||||
| Total operating revenues | 2,176 | 2,097 | ||||||||||||
| Operating Expenses: | ||||||||||||||
| Fuel and purchased power | 433 | 502 | ||||||||||||
| Natural gas purchased for resale | 171 | 169 | ||||||||||||
| Other operations and maintenance | 491 | 485 | ||||||||||||
| Depreciation and amortization | 398 | 367 | ||||||||||||
| Taxes other than income taxes | 151 | 144 | ||||||||||||
| Total operating expenses | 1,644 | 1,667 | ||||||||||||
| Operating Income | 532 | 430 | ||||||||||||
| Other Income, Net | 90 | 85 | ||||||||||||
| Interest Charges | 204 | 175 | ||||||||||||
| Income Before Income Taxes | 418 | 340 | ||||||||||||
| Income Taxes | 60 | 50 | ||||||||||||
| Net Income | 358 | 290 | ||||||||||||
| Less: Net Income Attributable to Noncontrolling Interests | 1 | 1 | ||||||||||||
| Net Income Attributable to Ameren Common Shareholders | $ | 357 | $ | 289 | ||||||||||
| Earnings per Common Share - Basic | $ | 1.29 | $ | 1.07 | ||||||||||
| Earnings per Common Share – Diluted | $ | 1.28 | $ | 1.07 | ||||||||||
| Weighted-average Common Shares Outstanding – Basic | 276.5 | 270.0 | ||||||||||||
| Weighted-average Common Shares Outstanding – Diluted | 278.4 | 271.4 | ||||||||||||
| March 31, 2026 | December 31, 2025 | ||||||||||
| ASSETS | |||||||||||
| Current Assets: | |||||||||||
| Cash and cash equivalents | $ | 13 | $ | 13 | |||||||
| Accounts receivable - trade (less allowance for doubtful accounts) | 703 | 665 | |||||||||
| Unbilled revenue | 298 | 415 | |||||||||
| Miscellaneous accounts receivable | 175 | 107 | |||||||||
| Inventories | 733 | 774 | |||||||||
| Current regulatory assets | 434 | 387 | |||||||||
| Other current assets | 211 | 210 | |||||||||
| Total current assets | 2,567 | 2,571 | |||||||||
| Property, Plant, and Equipment, Net | 40,471 | 39,313 | |||||||||
| Investments and Other Assets: | |||||||||||
| Nuclear decommissioning trust fund | 1,478 | 1,526 | |||||||||
| Goodwill | 411 | 411 | |||||||||
| Regulatory assets | 2,674 | 2,524 | |||||||||
| Pension and other postretirement benefits | 991 | 977 | |||||||||
| Other assets | 1,254 | 1,154 | |||||||||
| Total investments and other assets | 6,808 | 6,592 | |||||||||
| TOTAL ASSETS | $ | 49,846 | $ | 48,476 | |||||||
| LIABILITIES AND EQUITY | |||||||||||
| Current Liabilities: | |||||||||||
| Current maturities of long-term debt | $ | 1,123 | $ | 973 | |||||||
| Short-term debt | 1,178 | 643 | |||||||||
| Accounts and wages payable | 733 | 1,254 | |||||||||
| Interest accrued | 179 | 229 | |||||||||
| Customer deposits | 239 | 238 | |||||||||
| Other current liabilities | 674 | 570 | |||||||||
| Total current liabilities | 4,126 | 3,907 | |||||||||
| Long-term Debt, Net | 19,003 | 18,214 | |||||||||
| Deferred Credits and Other Liabilities: | |||||||||||
| Accumulated deferred income taxes and tax credits, net | 5,311 | 5,181 | |||||||||
| Regulatory liabilities | 6,251 | 6,255 | |||||||||
| Asset retirement obligations | 864 | 849 | |||||||||
| Other deferred credits and liabilities | 606 | 540 | |||||||||
| Total deferred credits and other liabilities | 13,032 | 12,825 | |||||||||
| Shareholders’ Equity: | |||||||||||
| Common stock | 3 | 3 | |||||||||
| Other paid-in capital, principally premium on common stock | 8,114 | 8,106 | |||||||||
| Retained earnings | 5,441 | 5,292 | |||||||||
| Accumulated other comprehensive loss | (2) | — | |||||||||
| Total shareholders’ equity | 13,556 | 13,401 | |||||||||
| Noncontrolling Interests | 129 | 129 | |||||||||
| Total equity | 13,685 | 13,530 | |||||||||
| TOTAL LIABILITIES AND EQUITY | $ | 49,846 | $ | 48,476 | |||||||
| Three Months Ended March 31, | |||||||||||
| 2026 | 2025 | ||||||||||
| Cash Flows From Operating Activities: | |||||||||||
| Net income | $ | 358 | $ | 290 | |||||||
| Adjustments to reconcile net income to net cash provided by operating activities: | |||||||||||
| Depreciation and amortization | 417 | 395 | |||||||||
| Amortization of nuclear fuel | 21 | 20 | |||||||||
| Amortization of debt issuance costs and premium/discounts | 5 | 5 | |||||||||
| Deferred income taxes and tax credits, net | 56 | 116 | |||||||||
| Allowance for equity funds used during construction | (31) | (16) | |||||||||
| Stock-based compensation costs | 8 | 7 | |||||||||
| Other | 9 | 7 | |||||||||
| Changes in assets and liabilities | (422) | (393) | |||||||||
| Net cash provided by operating activities | 421 | 431 | |||||||||
| Cash Flows From Investing Activities: | |||||||||||
| Capital expenditures | (1,574) | (1,064) | |||||||||
| Nuclear fuel expenditures | (22) | (18) | |||||||||
| Purchases of securities – nuclear decommissioning trust fund | (87) | (107) | |||||||||
| Sales and maturities of securities – nuclear decommissioning trust fund | 76 | 93 | |||||||||
| Other | (7) | 9 | |||||||||
| Net cash used in investing activities | (1,614) | (1,087) | |||||||||
| Cash Flows From Financing Activities: | |||||||||||
| Dividends on common stock | (208) | (191) | |||||||||
| Dividends paid to noncontrolling interest holders | (1) | (1) | |||||||||
| Short-term debt, net | 534 | 108 | |||||||||
| Maturities of long-term debt | (350) | (300) | |||||||||
| Issuances of long-term debt | 1,297 | 1,099 | |||||||||
| Issuances of common stock | 12 | 13 | |||||||||
| Employee payroll taxes related to stock-based compensation | (14) | (13) | |||||||||
| Debt issuance costs | (12) | (11) | |||||||||
| Net cash provided by financing activities | 1,258 | 704 | |||||||||
| Net change in cash, cash equivalents, and restricted cash | 65 | 48 | |||||||||
Cash, cash equivalents, and restricted cash at beginning of year(a) | 420 | 328 | |||||||||
Cash, cash equivalents, and restricted cash at end of period(b) | $ | 485 | $ | 376 | |||||||