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INCOME TAXES - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Deferred tax liabilities — |  |
Deferred income tax liabilities | $ 18,908 | $ 18,574
Deferred tax assets — |  |
Deferred income tax assets | 7,593 | 7,886
Valuation allowance | (333) | (206)
Net deferred income tax assets | 7,260 | 7,680
Net deferred income taxes liabilities | 11,648 | 10,894
Accumulated deferred income taxes – assets | (82) | (96)
Accumulated deferred income taxes – liabilities | 11,730 | 10,990
Accelerated depreciation |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 9,828 | 9,683
Property basis differences |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 3,025 | 2,647
Employee benefit obligations |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 1,067 | 979
Deferred tax assets — |  |
Deferred income tax assets | 897 | 985
AROs |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 727 | 833
Under recovered fuel and natural gas costs |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 318 | 601
AROs |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 1,886 | 1,902
Employee benefit obligations |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 746 | 797
Remaining book value of retired assets |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 360 | 369
Storm damage reserves |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 216 |
Premium on reacquired debt |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 57 | 63
Other |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 678 | 700
AROs |  |
Deferred tax assets — |  |
Deferred income tax assets | 2,613 | 2,735
CAMT Carryforwards |  |
Deferred tax assets — |  |
Deferred income tax assets | 40 |
ITC and PTC carryforwards |  |
Deferred tax assets — |  |
Deferred income tax assets | 1,380 | 1,387
Estimated loss on plants under construction |  |
Deferred tax assets — |  |
Deferred income tax assets | 773 | 857
Estimated loss on regulatory disallowance |  |
Deferred tax assets — |  |
Deferred income tax assets | 20 | 26
Other state deferred tax attributes |  |
Deferred tax assets — |  |
Deferred income tax assets | 366 | 363
Federal effect of net state deferred tax assets/liabilities |  |
Deferred tax assets — |  |
Deferred income tax assets | 402 | 418
Other property basis differences |  |
Deferred tax assets — |  |
Deferred income tax assets | 176 | 197
State effect of federal deferred taxes |  |
Deferred tax assets — |  |
Deferred income tax assets | 126 | 115
Other partnership basis differences |  |
Deferred tax assets — |  |
Deferred income tax assets | 60 | 85
Regulatory liability associated with the Tax Reform Legislation (not subject to normalization) |  |
Deferred tax assets — |  |
Deferred income tax assets | 18 | 34
Long-term debt fair value adjustment |  |
Deferred tax assets — |  |
Deferred income tax assets | 73 | 79
Other comprehensive losses |  |
Deferred tax assets — |  |
Deferred income tax assets | 48 | 67
Other |  |
Deferred tax assets — |  |
Deferred income tax assets | 601 | 538
Alabama Power |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 6,109 | 6,101
Deferred tax assets — |  |
Deferred income tax assets | 1,931 | 1,931
Valuation allowance | 0 | 0
Net deferred income tax assets | 1,931 | 1,931
Net deferred income taxes liabilities | 4,178 | 4,170
Accumulated deferred income taxes – assets | 0 | 0
Accumulated deferred income taxes – liabilities | 4,178 | 4,170
Alabama Power | Accelerated depreciation |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 2,583 | 2,566
Alabama Power | Property basis differences |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 1,497 | 1,444
Alabama Power | Employee benefit obligations |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 362 | 321
Deferred tax assets — |  |
Deferred income tax assets | 196 | 224
Alabama Power | AROs |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 458 | 476
Alabama Power | Under recovered fuel and natural gas costs |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 13 | 80
Alabama Power | AROs |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 658 | 667
Alabama Power | Employee benefit obligations |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 191 | 213
Alabama Power | Remaining book value of retired assets |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 168 | 143
Alabama Power | Storm damage reserves |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 0 |
Alabama Power | Premium on reacquired debt |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 8 | 9
Alabama Power | Other |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 171 | 182
Alabama Power | AROs |  |
Deferred tax assets — |  |
Deferred income tax assets | 1,116 | 1,143
Alabama Power | CAMT Carryforwards |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 |
Alabama Power | ITC and PTC carryforwards |  |
Deferred tax assets — |  |
Deferred income tax assets | 48 | 12
Alabama Power | Estimated loss on plants under construction |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 0
Alabama Power | Estimated loss on regulatory disallowance |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 0
Alabama Power | Other state deferred tax attributes |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 0
Alabama Power | Federal effect of net state deferred tax assets/liabilities |  |
Deferred tax assets — |  |
Deferred income tax assets | 197 | 215
Alabama Power | Other property basis differences |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 0
Alabama Power | State effect of federal deferred taxes |  |
Deferred tax assets — |  |
Deferred income tax assets | 126 | 115
Alabama Power | Other partnership basis differences |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 0
Alabama Power | Regulatory liability associated with the Tax Reform Legislation (not subject to normalization) |  |
Deferred tax assets — |  |
Deferred income tax assets | 18 | 30
Alabama Power | Long-term debt fair value adjustment |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 0
Alabama Power | Other comprehensive losses |  |
Deferred tax assets — |  |
Deferred income tax assets | 3 | 4
Alabama Power | Other |  |
Deferred tax assets — |  |
Deferred income tax assets | 227 | 188
Georgia Power |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 7,792 | 7,661
Deferred tax assets — |  |
Deferred income tax assets | 3,564 | 3,718
Valuation allowance | (157) | (75)
Net deferred income tax assets | 3,407 | 3,643
Net deferred income taxes liabilities | 4,385 | 4,018
Accumulated deferred income taxes – assets | 0 | 0
Accumulated deferred income taxes – liabilities | 4,385 | 4,018
Georgia Power | Accelerated depreciation |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 3,810 | 3,628
Georgia Power | Property basis differences |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 918 | 812
Georgia Power | Employee benefit obligations |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 470 | 446
Deferred tax assets — |  |
Deferred income tax assets | 279 | 316
Georgia Power | AROs |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 221 | 314
Georgia Power | Under recovered fuel and natural gas costs |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 305 | 508
Georgia Power | AROs |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 1,193 | 1,196
Georgia Power | Employee benefit obligations |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 237 | 260
Georgia Power | Remaining book value of retired assets |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 187 | 221
Georgia Power | Storm damage reserves |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 216 |
Georgia Power | Premium on reacquired debt |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 48 | 53
Georgia Power | Other |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 187 | 223
Georgia Power | AROs |  |
Deferred tax assets — |  |
Deferred income tax assets | 1,414 | 1,510
Georgia Power | CAMT Carryforwards |  |
Deferred tax assets — |  |
Deferred income tax assets | 18 |
Georgia Power | ITC and PTC carryforwards |  |
Deferred tax assets — |  |
Deferred income tax assets | 719 | 691
Georgia Power | Estimated loss on plants under construction |  |
Deferred tax assets — |  |
Deferred income tax assets | 773 | 857
Georgia Power | Estimated loss on regulatory disallowance |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 0
Georgia Power | Other state deferred tax attributes |  |
Deferred tax assets — |  |
Deferred income tax assets | 26 | 13
Georgia Power | Federal effect of net state deferred tax assets/liabilities |  |
Deferred tax assets — |  |
Deferred income tax assets | 100 | 92
Georgia Power | Other property basis differences |  |
Deferred tax assets — |  |
Deferred income tax assets | 75 | 83
Georgia Power | State effect of federal deferred taxes |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 0
Georgia Power | Other partnership basis differences |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 0
Georgia Power | Regulatory liability associated with the Tax Reform Legislation (not subject to normalization) |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 0
Georgia Power | Long-term debt fair value adjustment |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 0
Georgia Power | Other comprehensive losses |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 4
Georgia Power | Other |  |
Deferred tax assets — |  |
Deferred income tax assets | 160 | 152
Mississippi Power |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 727 | 714
Deferred tax assets — |  |
Deferred income tax assets | 358 | 382
Valuation allowance | (41) | (41)
Net deferred income tax assets | 317 | 341
Net deferred income taxes liabilities | 410 | 373
Accumulated deferred income taxes – assets | (82) | (96)
Accumulated deferred income taxes – liabilities | 492 | 469
Mississippi Power | Accelerated depreciation |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 344 | 339
Mississippi Power | Property basis differences |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 192 | 188
Mississippi Power | Employee benefit obligations |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 54 | 49
Deferred tax assets — |  |
Deferred income tax assets | 49 | 52
Mississippi Power | AROs |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 0 | 0
Mississippi Power | Under recovered fuel and natural gas costs |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 0 | 13
Mississippi Power | AROs |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 35 | 39
Mississippi Power | Employee benefit obligations |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 35 | 37
Mississippi Power | Remaining book value of retired assets |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 5 | 5
Mississippi Power | Storm damage reserves |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 0 |
Mississippi Power | Premium on reacquired debt |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 1 | 1
Mississippi Power | Other |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 61 | 43
Mississippi Power | AROs |  |
Deferred tax assets — |  |
Deferred income tax assets | 35 | 39
Mississippi Power | CAMT Carryforwards |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 |
Mississippi Power | ITC and PTC carryforwards |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 0
Mississippi Power | Estimated loss on plants under construction |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 0
Mississippi Power | Estimated loss on regulatory disallowance |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 0
Mississippi Power | Other state deferred tax attributes |  |
Deferred tax assets — |  |
Deferred income tax assets | 224 | 231
Mississippi Power | Federal effect of net state deferred tax assets/liabilities |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 0
Mississippi Power | Other property basis differences |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 0
Mississippi Power | State effect of federal deferred taxes |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 0
Mississippi Power | Other partnership basis differences |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 0
Mississippi Power | Regulatory liability associated with the Tax Reform Legislation (not subject to normalization) |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 3
Mississippi Power | Long-term debt fair value adjustment |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 0
Mississippi Power | Other comprehensive losses |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 0
Mississippi Power | Other |  |
Deferred tax assets — |  |
Deferred income tax assets | 50 | 57
Southern Power |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 1,323 | 1,360
Deferred tax assets — |  |
Deferred income tax assets | 638 | 773
Valuation allowance | (27) | (27)
Net deferred income tax assets | 611 | 746
Net deferred income taxes liabilities | 712 | 614
Accumulated deferred income taxes – assets | 0 | 0
Accumulated deferred income taxes – liabilities | 712 | 614
Southern Power | Accelerated depreciation |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 1,309 | 1,346
Southern Power | Property basis differences |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 0 | 0
Southern Power | Employee benefit obligations |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 13 | 12
Deferred tax assets — |  |
Deferred income tax assets | 16 | 10
Southern Power | AROs |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 0 | 0
Southern Power | Under recovered fuel and natural gas costs |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 0 | 0
Southern Power | AROs |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 0 | 0
Southern Power | Employee benefit obligations |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 0 | 0
Southern Power | Remaining book value of retired assets |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 0 | 0
Southern Power | Storm damage reserves |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 0 |
Southern Power | Premium on reacquired debt |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 0 | 0
Southern Power | Other |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 1 | 2
Southern Power | AROs |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 0
Southern Power | CAMT Carryforwards |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 |
Southern Power | ITC and PTC carryforwards |  |
Deferred tax assets — |  |
Deferred income tax assets | 384 | 481
Southern Power | Estimated loss on plants under construction |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 0
Southern Power | Estimated loss on regulatory disallowance |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 0
Southern Power | Other state deferred tax attributes |  |
Deferred tax assets — |  |
Deferred income tax assets | 49 | 49
Southern Power | Federal effect of net state deferred tax assets/liabilities |  |
Deferred tax assets — |  |
Deferred income tax assets | 23 | 27
Southern Power | Other property basis differences |  |
Deferred tax assets — |  |
Deferred income tax assets | 85 | 97
Southern Power | State effect of federal deferred taxes |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 0
Southern Power | Other partnership basis differences |  |
Deferred tax assets — |  |
Deferred income tax assets | 60 | 85
Southern Power | Regulatory liability associated with the Tax Reform Legislation (not subject to normalization) |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 0
Southern Power | Long-term debt fair value adjustment |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 0
Southern Power | Other comprehensive losses |  |
Deferred tax assets — |  |
Deferred income tax assets | 1 | 6
Southern Power | Other |  |
Deferred tax assets — |  |
Deferred income tax assets | 20 | 18
Southern Company Gas |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 2,283 | 2,041
Deferred tax assets — |  |
Deferred income tax assets | 493 | 377
Valuation allowance | (6) | (7)
Net deferred income tax assets | 487 | 370
Net deferred income taxes liabilities | 1,796 | 1,671
Accumulated deferred income taxes – assets | 0 | 0
Accumulated deferred income taxes – liabilities | 1,796 | 1,671
Southern Company Gas | Accelerated depreciation |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 1,575 | 1,576
Southern Company Gas | Property basis differences |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 412 | 189
Southern Company Gas | Employee benefit obligations |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 60 | 74
Deferred tax assets — |  |
Deferred income tax assets | 87 | 89
Southern Company Gas | AROs |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 0 | 0
Southern Company Gas | Under recovered fuel and natural gas costs |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 0 | 0
Southern Company Gas | AROs |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 0 | 0
Southern Company Gas | Employee benefit obligations |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 35 | 11
Southern Company Gas | Remaining book value of retired assets |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 0 | 0
Southern Company Gas | Storm damage reserves |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 0 |
Southern Company Gas | Premium on reacquired debt |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 0 | 0
Southern Company Gas | Other |  |
Deferred tax liabilities — |  |
Deferred income tax liabilities | 201 | 191
Southern Company Gas | AROs |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 0
Southern Company Gas | CAMT Carryforwards |  |
Deferred tax assets — |  |
Deferred income tax assets | 104 |
Southern Company Gas | ITC and PTC carryforwards |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 0
Southern Company Gas | Estimated loss on plants under construction |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 0
Southern Company Gas | Estimated loss on regulatory disallowance |  |
Deferred tax assets — |  |
Deferred income tax assets | 20 | 26
Southern Company Gas | Other state deferred tax attributes |  |
Deferred tax assets — |  |
Deferred income tax assets | 16 | 8
Southern Company Gas | Federal effect of net state deferred tax assets/liabilities |  |
Deferred tax assets — |  |
Deferred income tax assets | 107 | 101
Southern Company Gas | Other property basis differences |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 0
Southern Company Gas | State effect of federal deferred taxes |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 0
Southern Company Gas | Other partnership basis differences |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 0
Southern Company Gas | Regulatory liability associated with the Tax Reform Legislation (not subject to normalization) |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 0
Southern Company Gas | Long-term debt fair value adjustment |  |
Deferred tax assets — |  |
Deferred income tax assets | 73 | 79
Southern Company Gas | Other comprehensive losses |  |
Deferred tax assets — |  |
Deferred income tax assets | 0 | 0
Southern Company Gas | Other |  |
Deferred tax assets — |  |
Deferred income tax assets | $ 86 | $ 74

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