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v3.25.3

Revenue Customer Type (Details) $ in Millions | 12 Months Ended
--- | ---
Sep. 30, 2025 USD ($) Units | Sep. 30, 2024 USD ($) | Sep. 30, 2023 USD ($)
Electric revenue | $ 13,483 | $ 12,123 | $ 11,888
Bill credits for LTA | $ (231) | (215) | 199
Percentage of total operating revenues | 90.20% |  |
Total number of LPCs | Units | 153 |  |
Revenue capitalized during pre-commercial operations | $ (4) | (3) | (3)
Pandemic Relief Credit | $ 225 |  |
Number of LPCs signed flexibility agreement | Units | 109 |  |
Regulated Operating Revenue | $ 13,486 | 12,128 | 11,899
Regulated and Unregulated Operating Revenue | $ 13,672 | $ 12,314 | $ 12,054
Percent of sales of electricity to LPCs | 91.00% | 92.00% | 92.00%
MLGW's % of operating revenues | 9.00% | 9.00% | 9.00%
NES's % of operating revenues | 8.00% | 8.00% | 8.00%
Other Operating Segment |  |  |
Unregulated Operating Revenue | $ (186) | $ (186) | $ (155)
Off-System Sales |  |  |
Unregulated Operating Revenue | (7) | (8) | (14)
Pre-commercial Operations - Capitalized Revenue |  |  |
Unregulated Operating Revenue | 4 | (3) | (3)
ALABAMA |  |  |
Regulated Operating Revenue | 1,995 | 1,768 | 1,731
GEORGIA |  |  |
Regulated Operating Revenue | 329 | 295 | 284
KENTUCKY |  |  |
Regulated Operating Revenue | 850 | 776 | 773
MISSISSIPPI |  |  |
Regulated Operating Revenue | 1,254 | 1,150 | 1,146
NORTH CAROLINA |  |  |
Regulated Operating Revenue | 88 | 89 | 89
TENNESSEE |  |  |
Regulated Operating Revenue | 8,915 | 7,998 | 7,819
VIRGINIA |  |  |
Regulated Operating Revenue | $ 52 | 47 | 46
5-year contract arrangement [Member] |  |  |
Number of LPCs signed LTA | Units | 5 |  |
Percentage of total operating revenues | 12.40% |  |
Revenues | $ 1,698 |  |
20-year Termination Notice |  |  |
Number of LPCs signed LTA | Units | 148 |  |
Percentage of total operating revenues | 77.80% |  |
Revenues | $ 10,636 |  |
Federal agencies and other [Member] |  |  |
Regulated Operating Revenue | 139 | 125 | 135
Local Power Company [Member] |  |  |
Electric revenue | 12,334 |  |
Regulated Operating Revenue | 12,334 | 11,138 | 10,903
Industries Directly Served [Member] |  |  |
Regulated Operating Revenue | $ 1,017 | $ 868 | $ 864

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