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Segment Information (Tables) | 12 Months Ended
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Dec. 31, 2025
Segment Reporting [Abstract] |
Schedule Of Segment Reporting Information, By Segment | The following tables present information about the reported revenue and specified items reflected in net income attributable to common shareholders and capital expenditures by segment at Ameren and Ameren Illinois for the years ended December 31, 2025, 2024, and 2023. Ameren, Ameren Missouri, and Ameren Illinois management review segment capital expenditure information rather than any individual or total asset amount. Ameren
| Reportable Segments |  |  |  |  |  |  |  |
| Ameren Missouri |  | Ameren Illinois Electric Distribution |  | Ameren Illinois Natural Gas |  | Ameren Transmission |  | Other |  | Intersegment Eliminations |  | Ameren |  |
2025 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
External revenues | $ | 4,763 |  |  | $ | 2,393 |  |  | $ | 968 |  |  | $ | 675 |  |  | $ | — |  |  | $ | — |  |  | $ | 8,799 |  |  |
Intersegment revenues | 32 |  |  | 6 |  |  | — |  |  | 187 |  |  | — |  |  | (225) |  |  | — |  |  |
Revenue | 4,795 |  |  | 2,399 |  |  | 968 |  |  | 862 |  |  | — |  |  | (225) |  |  | 8,799 |  |  |
Fuel and purchased power(a) | (1,538) |  |  | (941) |  |  | — |  |  | — |  |  | — |  |  | 173 |  |  | (2,306) |  |  |
Natural gas purchased for resale(a) | (65) |  |  | — |  |  | (283) |  |  | — |  |  | — |  |  | — |  |  | (348) |  |  |
Other operations and maintenance expenses(a) | (1,029) |  |  | (656) |  |  | (233) |  |  | (74) |  |  | (34) |  |  | 52 |  |  | (1,974) |  |  |
Other segment items |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Depreciation and amortization | (860) |  |  | (373) |  |  | (128) |  |  | (199) |  |  | (8) |  |  | — |  |  | (1,568) |  |  |
Taxes other than income taxes | (393) |  |  | (82) |  |  | (82) |  |  | (9) |  |  | (11) |  |  | — |  |  | (577) |  |  |
Other income, net | 180 |  |  | 89 |  |  | 19 |  |  | 24 |  |  | 42 |  |  | (7) |  |  | 347 |  |  |
Interest charges | (297) |  |  | (107) |  |  | (65) |  |  | (120) |  | (b) | (194) |  |  | 7 |  |  | (776) |  |  |
Income taxes (benefit) | (43) |  |  | (47) |  |  | (38) |  |  | (68) |  |  | 60 |  |  | — |  |  | (136) |  |  |
Noncontrolling interests – preferred stock dividends | (3) |  |  | (1) |  |  | — |  |  | (1) |  |  | — |  |  | — |  |  | (5) |  |  |
Net income (loss) attributable to Ameren common shareholders | $ | 747 |  |  | $ | 281 |  |  | $ | 158 |  |  | $ | 415 |  |  | $ | (145) |  |  | $ | — |  |  | $ | 1,456 |  |  |
Interest income | $ | 9 |  |  | $ | 30 |  |  | $ | — |  |  | $ | 3 |  |  | $ | 6 |  |  | $ | (7) |  |  | $ | 41 |  |  |
Capital expenditures | 2,502 |  |  | 635 |  |  | 283 |  |  | 717 |  |  | 8 |  |  | (17) |  |  | 4,128 |  |  |
2024 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
External revenues | $ | 3,960 |  |  | $ | 2,088 |  |  | $ | 938 |  |  | $ | 637 |  |  | $ | — |  |  | $ | — |  |  | $ | 7,623 |  |  |
Intersegment revenues | 33 |  |  | 1 |  |  | — |  |  | 144 |  |  | — |  |  | (178) |  |  | — |  |  |
Revenue | 3,993 |  |  | 2,089 |  |  | 938 |  |  | 781 |  |  | — |  |  | (178) |  |  | 7,623 |  |  |
Fuel and purchased power(a) | (1,071) |  |  | (740) |  |  | — |  |  | — |  |  | — |  |  | 130 |  |  | (1,681) |  |  |
Natural gas purchased for resale(a) | (60) |  |  | — |  |  | (260) |  |  | — |  |  | — |  |  | — |  |  | (320) |  |  |
Other operations and maintenance expenses(a) | (1,050) |  |  | (619) |  |  | (230) |  |  | (70) |  |  | (48) |  |  | 48 |  |  | (1,969) |  |  |
Other segment items |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Depreciation and amortization | (917) |  |  | (369) |  |  | (129) |  |  | (167) |  |  | (8) |  |  | — |  |  | (1,590) |  |  |
Taxes other than income taxes | (372) |  |  | (75) |  |  | (78) |  |  | (9) |  |  | (13) |  |  | — |  |  | (547) |  |  |
Other income, net | 196 |  |  | 97 |  |  | 27 |  |  | 26 |  |  | 83 |  |  | (12) |  |  | 417 |  |  |
Interest charges | (244) |  |  | (98) |  |  | (63) |  |  | (117) |  | (b) | (153) |  |  | 12 |  |  | (663) |  |  |
Income taxes (benefit) | 87 |  |  | (50) |  |  | (56) |  |  | (120) |  |  | 56 |  |  | — |  |  | (83) |  |  |
Noncontrolling interests – preferred stock dividends | (3) |  |  | (1) |  |  | — |  |  | (1) |  |  | — |  |  | — |  |  | (5) |  |  |
Net income (loss) attributable to Ameren common shareholders | $ | 559 |  |  | $ | 234 |  |  | $ | 149 |  |  | $ | 323 |  |  | $ | (83) |  |  | $ | — |  |  | $ | 1,182 |  |  |
Interest income | $ | 8 |  |  | $ | 28 |  |  | $ | 1 |  |  | $ | 6 |  |  | $ | 10 |  |  | $ | (12) |  |  | $ | 41 |  |  |
Capital expenditures | 2,712 |  |  | 579 |  |  | 264 |  |  | 758 |  |  | 7 |  |  | (1) |  |  | 4,319 |  |  |
| Reportable Segments |  |  |  |  |  |  |  |
| Ameren Missouri |  | Ameren Illinois Electric Distribution |  | Ameren Illinois Natural Gas |  | Ameren Transmission |  | Other |  | Intersegment Eliminations |  | Ameren |  |
2023 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
External revenues | $ | 3,825 |  |  | $ | 2,217 |  |  | $ | 897 |  |  | $ | 561 |  |  | $ | — |  |  | $ | — |  |  | $ | 7,500 |  |  |
Intersegment revenues | 34 |  |  | 1 |  |  | — |  |  | 116 |  |  | — |  |  | (151) |  |  | — |  |  |
Revenue | 3,859 |  |  | 2,218 |  |  | 897 |  |  | 677 |  |  | — |  |  | (151) |  |  | 7,500 |  |  |
Fuel and purchased power(a) | (997) |  |  | (933) |  |  | — |  |  | — |  |  | — |  |  | 118 |  |  | (1,812) |  |  |
Natural gas purchased for resale(a) | (79) |  |  | — |  |  | (276) |  |  | — |  |  | — |  |  | — |  |  | (355) |  |  |
Other operations and maintenance expenses(a) | (1,003) |  |  | (532) |  |  | (237) |  |  | (60) |  |  | (67) |  |  | 33 |  |  | (1,866) |  |  |
Other segment items |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Depreciation and amortization | (783) |  |  | (351) |  |  | (108) |  |  | (138) |  |  | (7) |  |  | — |  |  | (1,387) |  |  |
Taxes other than income taxes | (360) |  |  | (75) |  |  | (67) |  |  | (8) |  |  | (12) |  |  | — |  |  | (522) |  |  |
Other income, net | 130 |  |  | 103 |  |  | 30 |  |  | 28 |  |  | 62 |  |  | (5) |  |  | 348 |  |  |
Interest charges | (227) |  |  | (89) |  |  | (55) |  |  | (96) |  | (b) | (104) |  |  | 5 |  |  | (566) |  |  |
Income taxes (benefit) | 8 |  |  | (82) |  |  | (50) |  |  | (106) |  |  | 47 |  |  | — |  |  | (183) |  |  |
Noncontrolling interests – preferred stock dividends | (3) |  |  | (1) |  |  | — |  |  | (1) |  |  | — |  |  | — |  |  | (5) |  |  |
Net income (loss) attributable to Ameren common shareholders | $ | 545 |  |  | $ | 258 |  |  | $ | 134 |  |  | $ | 296 |  |  | $ | (81) |  |  | $ | — |  |  | $ | 1,152 |  |  |
Interest income | $ | 11 |  |  | $ | 19 |  |  | $ | 1 |  |  | $ | 2 |  |  | $ | 5 |  |  | $ | (5) |  |  | $ | 33 |  |  |
Capital expenditures | 1,760 |  |  | 752 |  |  | 299 |  |  | 804 |  |  | 9 |  |  | (27) |  |  | 3,597 |  |  |
(a)Significant segment expense that is regularly provided to the CODMs. Intersegment expenses are included within the amounts shown. (b)Ameren Transmission interest charges include an allocation of financing costs from Ameren (parent). Ameren Illinois
| Reportable Segments |  |  |  |  |
| Ameren Illinois Electric Distribution |  | Ameren Illinois Natural Gas |  | Ameren Illinois Transmission |  | Intersegment Eliminations |  | Ameren Illinois |
2025 |  |  |  |  |  |  |  |  |  |
External revenues | $ | 2,399 |  |  | $ | 968 |  |  | $ | 477 |  |  | $ | — |  |  | $ | 3,844 |  |
Intersegment revenues | — |  |  | — |  |  | 160 |  |  | (160) |  |  | — |  |
Revenue | 2,399 |  |  | 968 |  |  | 637 |  |  | (160) |  |  | 3,844 |  |
Purchased power(a) | (941) |  |  | — |  |  | — |  |  | 160 |  |  | (781) |  |
Natural gas purchased for resale(a) | — |  |  | (283) |  |  | — |  |  | — |  |  | (283) |  |
Other operations and maintenance expenses(a) | (656) |  |  | (233) |  |  | (56) |  |  | — |  |  | (945) |  |
Other segment items |  |  |  |  |  |  |  |  |  |
Depreciation and amortization | (373) |  |  | (128) |  |  | (151) |  |  | — |  |  | (652) |  |
Taxes other than income taxes | (82) |  |  | (82) |  |  | (5) |  |  | — |  |  | (169) |  |
Other income, net | 89 |  |  | 19 |  |  | 28 |  |  | — |  |  | 136 |  |
Interest charges | (107) |  |  | (65) |  |  | (88) |  |  | — |  |  | (260) |  |
Income taxes | (47) |  |  | (38) |  |  | (68) |  |  | — |  |  | (153) |  |
Noncontrolling interests – preferred stock dividends | (1) |  |  | — |  |  | (1) |  |  | — |  |  | (2) |  |
Net income available to common shareholder | $ | 281 |  |  | $ | 158 |  |  | $ | 296 |  |  | $ | — |  |  | $ | 735 |  |
Interest income | $ | 30 |  |  | $ | — |  |  | $ | 2 |  |  | $ | — |  |  | $ | 32 |  |
Capital expenditures | 635 |  |  | 283 |  |  | 563 |  |  | — |  |  | 1,481 |  |
2024 |  |  |  |  |  |  |  |  |  |
External revenues | $ | 2,089 |  |  | $ | 938 |  |  | $ | 445 |  |  | $ | — |  |  | $ | 3,472 |  |
Intersegment revenues | — |  |  | — |  |  | 119 |  |  | (119) |  |  | — |  |
Revenue | 2,089 |  |  | 938 |  |  | 564 |  |  | (119) |  |  | 3,472 |  |
Purchased power(a) | (740) |  |  | — |  |  | — |  |  | 119 |  |  | (621) |  |
Natural gas purchased for resale(a) | — |  |  | (260) |  |  | — |  |  | — |  |  | (260) |  |
Other operations and maintenance expenses(a) | (619) |  |  | (230) |  |  | (57) |  |  | — |  |  | (906) |  |
Other segment items |  |  |  |  |  |  |  |  |  |
Depreciation and amortization | (369) |  |  | (129) |  |  | (121) |  |  | — |  |  | (619) |  |
Taxes other than income taxes | (75) |  |  | (78) |  |  | (4) |  |  | — |  |  | (157) |  |
Other income, net | 97 |  |  | 27 |  |  | 23 |  |  | — |  |  | 147 |  |
Interest charges | (98) |  |  | (63) |  |  | (80) |  |  | — |  |  | (241) |  |
Income taxes | (50) |  |  | (56) |  |  | (87) |  |  | — |  |  | (193) |  |
Noncontrolling interests – preferred stock dividends | (1) |  |  | — |  |  | (1) |  |  | — |  |  | (2) |  |
Net income available to common shareholder | $ | 234 |  |  | $ | 149 |  |  | $ | 237 |  |  | $ | — |  |  | $ | 620 |  |
Interest income | $ | 28 |  |  | $ | 1 |  |  | $ | 3 |  |  | $ | — |  |  | $ | 32 |  |
Capital expenditures | 579 |  |  | 264 |  |  | 624 |  |  | — |  |  | 1,467 |  |
| Reportable Segments |  |  |  |  |
| Ameren Illinois Electric Distribution |  | Ameren Illinois Natural Gas |  | Ameren Illinois Transmission |  | Intersegment Eliminations |  | Ameren Illinois |
2023 |  |  |  |  |  |  |  |  |  |
External revenues | $ | 2,218 |  |  | $ | 897 |  |  | $ | 367 |  |  | $ | — |  |  | $ | 3,482 |  |
Intersegment revenues | — |  |  | — |  |  | 113 |  |  | (113) |  |  | — |  |
Revenue | 2,218 |  |  | 897 |  |  | 480 |  |  | (113) |  |  | 3,482 |  |
Purchased power(a) | (933) |  |  | — |  |  | — |  |  | 113 |  |  | (820) |  |
Natural gas purchased for resale(a) | — |  |  | (276) |  |  | — |  |  | — |  |  | (276) |  |
Other operations and maintenance expenses(a) | (532) |  |  | (237) |  |  | (49) |  |  | — |  |  | (818) |  |
Other segment items |  |  |  |  |  |  |  |  |  |
Depreciation and amortization | (351) |  |  | (108) |  |  | (97) |  |  | — |  |  | (556) |  |
Taxes other than income taxes | (75) |  |  | (67) |  |  | (4) |  |  | — |  |  | (146) |  |
Other income, net | 103 |  |  | 30 |  |  | 23 |  |  | — |  |  | 156 |  |
Interest charges | (89) |  |  | (55) |  |  | (60) |  |  | — |  |  | (204) |  |
Income taxes | (82) |  |  | (50) |  |  | (77) |  |  | — |  |  | (209) |  |
Noncontrolling interests – preferred stock dividends | (1) |  |  | — |  |  | (1) |  |  | — |  |  | (2) |  |
Net income available to common shareholder | $ | 258 |  |  | $ | 134 |  |  | $ | 215 |  |  | $ | — |  |  | $ | 607 |  |
Interest income | $ | 19 |  |  | $ | 1 |  |  | $ | 1 |  |  | $ | — |  |  | $ | 21 |  |
Capital expenditures | 752 |  |  | 299 |  |  | 680 |  |  | — |  |  | 1,731 |  |
(a)Significant segment expense that is regularly provided to the CODMs. Intersegment expenses are included within the amounts shown.
Disaggregation of Revenue | The following tables present disaggregated revenues by segment at Ameren and Ameren Illinois for the years ended December 31, 2025, 2024, and 2023. Economic factors affect the nature, timing, amount, and uncertainty of revenues and cash flows in a similar manner across customer classes. Revenues from alternative revenue programs have a similar distribution among customer classes as revenues from contracts with customers. Other revenues not associated with contracts with customers are presented in the Other customer classification, along with electric transmission and off-system sales and capacity revenues. Ameren
| Ameren Missouri |  | Ameren Illinois Electric Distribution |  | Ameren Illinois Natural Gas |  | Ameren Transmission |  |  |  | Intersegment Eliminations |  | Ameren |
2025 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Residential | $ | 1,839 |  |  | $ | 1,483 |  |  | $ | — |  |  | $ | — |  |  |  |  | $ | — |  |  | $ | 3,322 |  |
Commercial | 1,450 |  |  | 785 |  |  | — |  |  | — |  |  |  |  | — |  |  | 2,235 |  |
Industrial | 342 |  |  | 199 |  |  | — |  |  | — |  |  |  |  | — |  |  | 541 |  |
Other | 1,000 |  |  | (68) |  |  | — |  |  | 862 |  |  |  |  | (224) |  |  | 1,570 |  |
Total electric revenues | $ | 4,631 |  |  | $ | 2,399 |  |  | $ | — |  |  | $ | 862 |  |  |  |  | $ | (224) |  |  | $ | 7,668 |  |
Residential | $ | 101 |  |  | $ | — |  |  | $ | 680 |  |  | $ | — |  |  |  |  | $ | — |  |  | $ | 781 |  |
Commercial | 44 |  |  | — |  |  | 185 |  |  | — |  |  |  |  | — |  |  | 229 |  |
Industrial | 5 |  |  | — |  |  | 12 |  |  | — |  |  |  |  | — |  |  | 17 |  |
Other | 14 |  |  | — |  |  | 91 |  |  | — |  |  |  |  | (1) |  |  | 104 |  |
Total gas revenues | $ | 164 |  |  | $ | — |  |  | $ | 968 |  |  | $ | — |  |  |  |  | $ | (1) |  |  | $ | 1,131 |  |
Total revenues(a) | $ | 4,795 |  |  | $ | 2,399 |  |  | $ | 968 |  |  | $ | 862 |  |  |  |  | $ | (225) |  |  | $ | 8,799 |  |
2024 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Residential | $ | 1,638 |  |  | $ | 1,254 |  |  | $ | — |  |  | $ | — |  |  |  |  | $ | — |  |  | $ | 2,892 |  |
Commercial | 1,313 |  |  | 680 |  |  | — |  |  | — |  |  |  |  | — |  |  | 1,993 |  |
Industrial | 311 |  |  | 178 |  |  | — |  |  | — |  |  |  |  | — |  |  | 489 |  |
Other | 585 |  |  | (23) |  |  | — |  |  | 781 |  |  |  |  | (177) |  |  | 1,166 |  |
Total electric revenues | $ | 3,847 |  |  | $ | 2,089 |  |  | $ | — |  |  | $ | 781 |  |  |  |  | $ | (177) |  |  | $ | 6,540 |  |
Residential | $ | 90 |  |  | $ | — |  |  | $ | 661 |  |  | $ | — |  |  |  |  | $ | — |  |  | $ | 751 |  |
Commercial | 37 |  |  | — |  |  | 166 |  |  | — |  |  |  |  | — |  |  | 203 |  |
Industrial | 4 |  |  | — |  |  | 10 |  |  | — |  |  |  |  | — |  |  | 14 |  |
Other | 15 |  |  | — |  |  | 101 |  |  | — |  |  |  |  | (1) |  |  | 115 |  |
Total gas revenues | $ | 146 |  |  | $ | — |  |  | $ | 938 |  |  | $ | — |  |  |  |  | $ | (1) |  |  | $ | 1,083 |  |
Total revenues(a) | $ | 3,993 |  |  | $ | 2,089 |  |  | $ | 938 |  |  | $ | 781 |  |  |  |  | $ | (178) |  |  | $ | 7,623 |  |
2023 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Residential | $ | 1,577 |  |  | $ | 1,344 |  |  | $ | — |  |  | $ | — |  |  |  |  | $ | — |  |  | $ | 2,921 |  |
Commercial | 1,280 |  |  | 747 |  |  | — |  |  | — |  |  |  |  | — |  |  | 2,027 |  |
Industrial | 306 |  |  | 186 |  |  | — |  |  | — |  |  |  |  | — |  |  | 492 |  |
Other | 531 |  |  | (59) |  |  | — |  |  | 677 |  |  |  |  | (150) |  |  | 999 |  |
Total electric revenues | $ | 3,694 |  |  | $ | 2,218 |  |  | $ | — |  |  | $ | 677 |  |  |  |  | $ | (150) |  |  | $ | 6,439 |  |
Residential | $ | 100 |  |  | $ | — |  |  | $ | 657 |  |  | $ | — |  |  |  |  | $ | — |  |  | $ | 757 |  |
Commercial | 46 |  |  | — |  |  | 164 |  |  | — |  |  |  |  | — |  |  | 210 |  |
Industrial | 5 |  |  | — |  |  | 14 |  |  | — |  |  |  |  | — |  |  | 19 |  |
Other | 14 |  |  | — |  |  | 62 |  |  | — |  |  |  |  | (1) |  |  | 75 |  |
Total gas revenues | $ | 165 |  |  | $ | — |  |  | $ | 897 |  |  | $ | — |  |  |  |  | $ | (1) |  |  | $ | 1,061 |  |
Total revenues(a) | $ | 3,859 |  |  | $ | 2,218 |  |  | $ | 897 |  |  | $ | 677 |  |  |  |  | $ | (151) |  |  | $ | 7,500 |  |
(a)The following table presents increases/(decreases) in revenues from alternative revenue programs and other revenues not from contracts with customers for the years ended December 31, 2025, 2024, and 2023:
| Ameren Missouri |  | Ameren Illinois Electric Distribution |  | Ameren Illinois Natural Gas |  | Ameren Transmission |  | Intersegment Eliminations |  | Ameren |
2025 |  |  |  |  |  |  |  |  |  |  |  |
Revenues from alternative revenue programs | $ | (5) |  |  | $ | (135) |  |  | $ | (34) |  |  | $ | (26) |  |  | $ | — |  |  | $ | (200) |  |
Other revenues not from contracts with customers | 6 |  | (a) | 13 |  |  | 3 |  |  | — |  |  | (4) |  |  | 18 |  | (a)
2024 |  |  |  |  |  |  |  |  |  |  |  |
Revenues from alternative revenue programs | $ | 4 |  |  | $ | (43) |  |  | $ | (3) |  |  | $ | 33 |  |  | $ | — |  |  | $ | (9) |  |
Other revenues not from contracts with customers | 7 |  | (a) | 10 |  |  | 2 |  |  | — |  |  | — |  |  | 19 |  | (a)
2023 |  |  |  |  |  |  |  |  |  |  |  |
Revenues from alternative revenue programs | $ | (5) |  |  | $ | 116 |  |  | $ | 49 |  |  | $ | 19 |  |  | $ | — |  |  | $ | 179 |  |
Other revenues not from contracts with customers | (9) |  | (a) | 7 |  |  | 2 |  |  | — |  |  | — |  |  | — |  | (a)
(a)Includes net realized gains and losses on derivative power contracts. Ameren Illinois
| Ameren Illinois Electric Distribution |  | Ameren Illinois Natural Gas |  | Ameren Illinois Transmission |  | Intersegment Eliminations |  | Ameren Illinois |
2025 |  |  |  |  |  |  |  |  |  |
Residential | $ | 1,483 |  |  | $ | 680 |  |  | $ | — |  |  | $ | — |  |  | $ | 2,163 |  |
Commercial | 785 |  |  | 185 |  |  | — |  |  | — |  |  | 970 |  |
Industrial | 199 |  |  | 12 |  |  | — |  |  | — |  |  | 211 |  |
Other | (68) |  |  | 91 |  |  | 637 |  |  | (160) |  |  | 500 |  |
Total revenues(a) | $ | 2,399 |  |  | $ | 968 |  |  | $ | 637 |  |  | $ | (160) |  |  | $ | 3,844 |  |
2024 |  |  |  |  |  |  |  |  |  |
Residential | $ | 1,254 |  |  | $ | 661 |  |  | $ | — |  |  | $ | — |  |  | $ | 1,915 |  |
Commercial | 680 |  |  | 166 |  |  | — |  |  | — |  |  | 846 |  |
Industrial | 178 |  |  | 10 |  |  | — |  |  | — |  |  | 188 |  |
Other | (23) |  |  | 101 |  |  | 564 |  |  | (119) |  |  | 523 |  |
Total revenues(a) | $ | 2,089 |  |  | $ | 938 |  |  | $ | 564 |  |  | $ | (119) |  |  | $ | 3,472 |  |
2023 |  |  |  |  |  |  |  |  |  |
Residential | $ | 1,344 |  |  | $ | 657 |  |  | $ | — |  |  | $ | — |  |  | $ | 2,001 |  |
Commercial | 747 |  |  | 164 |  |  | — |  |  | — |  |  | 911 |  |
Industrial | 186 |  |  | 14 |  |  | — |  |  | — |  |  | 200 |  |
Other | (59) |  |  | 62 |  |  | 480 |  |  | (113) |  |  | 370 |  |
Total revenues(a) | $ | 2,218 |  |  | $ | 897 |  |  | $ | 480 |  |  | $ | (113) |  |  | $ | 3,482 |  |
(a)The following table presents increases/(decreases) in revenues from alternative revenue programs and other revenues not from contracts with customers for the Ameren Illinois segments for the years ended December 31, 2025, 2024, and 2023:
| Ameren Illinois Electric Distribution |  | Ameren Illinois Natural Gas |  | Ameren Illinois Transmission |  | Ameren Illinois
2025 |  |  |  |  |  |  |
Revenues from alternative revenue programs | $ | (135) |  |  | $ | (34) |  |  | $ | (19) |  |  | $ | (188) |
Other revenues not from contracts with customers | 13 |  |  | 3 |  |  | — |  |  | 16 |
2024 |  |  |  |  |  |  |
Revenues from alternative revenue programs | $ | (43) |  |  | $ | (3) |  |  | $ | 29 |  |  | $ | (17) |
Other revenues not from contracts with customers | 10 |  |  | 2 |  |  | — |  |  | 12 |
2023 |  |  |  |  |  |  |
Revenues from alternative revenue programs | $ | 116 |  |  | $ | 49 |  |  | $ | 12 |  |  | $ | 177 |
Other revenues not from contracts with customers | 7 |  |  | 2 |  |  | — |  |  | 9 |

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