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VALUATION AND QUALIFYING ACCOUNTS (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Provision for uncollectible accounts: |  |  |
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] |  |  |
Balance at Beginning of Period | $ 68 | $ 71 | $ 78
Charged to Income | 119 | 87 | 71
Charged to Other Accounts | (1) | 3 | (1)
Deductions | 112 | 93 | 77
Balance at End of Period | 74 | 68 | 71
Provision for uncollectible accounts: | Alabama Power |  |  |
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] |  |  |
Balance at Beginning of Period | 16 | 14 | 14
Charged to Income | 26 | 16 | 10
Charged to Other Accounts | 0 | 0 | 0
Deductions | 20 | 14 | 10
Balance at End of Period | 22 | 16 | 14
Provision for uncollectible accounts: | Georgia Power |  |  |
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] |  |  |
Balance at Beginning of Period | 4 | 3 | 2
Charged to Income | 51 | 26 | 21
Charged to Other Accounts | 0 | 0 | 0
Deductions | 40 | 25 | 20
Balance at End of Period | 15 | 4 | 3
Provision for uncollectible accounts: | Mississippi Power |  |  |
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] |  |  |
Balance at Beginning of Period | 1 | 1 | 1
Charged to Income | 2 | 2 | 1
Charged to Other Accounts | 0 | 0 | 1
Deductions | 2 | 2 | 2
Balance at End of Period | 1 | 1 | 1
Provision for uncollectible accounts: | Southern Power |  |  |
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] |  |  |
Balance at Beginning of Period | 1 | 1 | 5
Charged to Income | (1) | 0 | (2)
Charged to Other Accounts | 0 | 0 | 0
Deductions | 0 | 0 | 2
Balance at End of Period | 0 | 1 | 1
Provision for uncollectible accounts: | Southern Company Gas |  |  |
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] |  |  |
Balance at Beginning of Period | 44 | 50 | 39
Charged to Income | 39 | 43 | 55
Charged to Other Accounts | (1) | 3 | 0
Deductions | 49 | 52 | 44
Balance at End of Period | 33 | 44 | 50
Tax valuation allowance (net state) |  |  |
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] |  |  |
Balance at Beginning of Period | 168 | 207 | 169
Charged to Income | 97 | (14) | 68
Charged to Other Accounts | 3 | (25) | (30)
Deductions | 0 | 0 | 0
Balance at End of Period | 268 | 168 | 207
Tax valuation allowance (net state) | Georgia Power |  |  |
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] |  |  |
Balance at Beginning of Period | 60 | 98 | 58
Charged to Income | 97 | (15) | 70
Charged to Other Accounts | (33) | (23) | (30)
Deductions | 0 | 0 | 0
Balance at End of Period | 124 | 60 | 98
Tax valuation allowance (net state) | Mississippi Power |  |  |
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] |  |  |
Balance at Beginning of Period | 32 | 32 | 32
Charged to Income | 0 | 0 | 0
Charged to Other Accounts | 0 | 0 | 0
Deductions | 0 | 0 | 0
Balance at End of Period | 32 | 32 | 32
Tax valuation allowance (net state) | Southern Power |  |  |
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] |  |  |
Balance at Beginning of Period | 21 | 21 | 21
Charged to Income | 0 | 0 | 0
Charged to Other Accounts | 0 | 0 | 0
Deductions | 0 | 0 | 0
Balance at End of Period | 21 | 21 | 21
Tax valuation allowance (net state) | Southern Company Gas |  |  |
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] |  |  |
Balance at Beginning of Period | 5 | 7 | 7
Charged to Income | 0 | 0 | 0
Charged to Other Accounts | (1) | (2) | 0
Deductions | 0 | 0 | 0
Balance at End of Period | $ 4 | $ 5 | $ 7

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