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Regulatory Matters | 9 Months Ended
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Sep. 30, 2025
Regulated Operations [Abstract] |
Regulatory Matters | REGULATORY MATTERS See Note 2 to the financial statements in Item 8 of the Form 10-K for additional information relating to regulatory matters. The fuel and natural gas cost recovery balances for the traditional electric operating companies and Southern Company Gas, respectively, at September 30, 2025 and December 31, 2024 were as follows:
Regulatory Clause | Balance Sheet Line Item | At September 30, 2025 | At December 31, 2024
|  | (in millions)
Alabama Power |  |  |
Rate ECR | Other regulatory assets, current | $ | 14 |  | $ | — |
| Other regulatory assets, deferred | 69 |  | — |
| Other regulatory liabilities, current | — |  | 29 |
Georgia Power |  |  |
Fuel Cost Recovery | Receivables – under recovered retail fuel clause revenues | $ | 487 |  | $ | 713 |
| Deferred under recovered retail fuel clause revenues | 197 |  | 453 |
Mississippi Power |  |  |
Fuel Cost Recovery(*) | Receivables – customer accounts, net | $ | 30 |  | $ | — |
| Deferred under recovered retail fuel clause revenues | — |  | 32 |
| Over recovered retail fuel clause revenues | — |  | 32 |
Southern Company Gas |  |  |
Natural Gas Cost Recovery | Natural gas cost over recovery | $ | 163 |  | $ | 193 |
(*)Mississippi Power also has wholesale MRA and Market Based (MB) fuel cost recovery factors. At September 30, 2025 and December 31, 2024, wholesale MRA fuel cost over recovery was immaterial and $19 million, respectively, and was included in other current liabilities on Mississippi Power's balance sheets. The wholesale MB fuel cost recovery was immaterial for both periods presented. Alabama Power Petition for Certificate of Convenience and Necessity On August 13, 2025, the Alabama PSC approved Alabama Power's petition for a certificate of convenience and necessity authorizing Alabama Power to complete the acquisition of Tenaska Alabama Partners, L.P., which had been approved by the FERC on June 6, 2025. The transaction closed on September 30, 2025. Tenaska Alabama Partners, L.P. had owned and operated the Lindsay Hill Generating Station, an approximately 855-MW combined cycle generation facility in Autauga County, Alabama. Alabama Power expects to recover all approved costs associated with the acquisition through existing rate mechanisms as outlined in Note 2 to the financial statements under "Alabama Power – Petition for Certificate of Convenience and Necessity" in Item 8 of the Form 10-K. See Note (K) under "Alabama Power" for additional information. Jurisdictional Separation Study Order On June 5, 2025, the Alabama PSC approved an order authorizing Alabama Power to implement changes related to the Jurisdictional Separation Study (JSS) under Rate RSE, which allocates costs between retail and other electric services. For 2026, a revised JSS allocation factor will account for system capacity previously allocated to wholesale electric services that will be used for retail electric service starting January 1, 2026. In addition, Alabama Power is authorized to establish a regulatory asset to defer certain costs associated with this capacity for 2026, and those costs are estimated to be approximately $100 million. Beginning in 2027, Alabama Power will amortize the regulatory asset on a levelized basis over a period not exceeding 10 years. Rate NDR Beginning with July 2025 billings, the NDR reserve maintenance charge was suspended and the reserve establishment charge was activated as a result of the NDR balance falling below $50 million. Alabama Power expects to collect $18 million in the second half of 2025 and approximately $36 million annually beginning in 2026 under Rate NDR unless the NDR balance exceeds $75 million. At September 30, 2025, Alabama Power's regulatory asset balance related to NDR was $4 million. Rate NDR is intended to allow recovery of any existing deferred storm-related operations and maintenance costs and any future reserve deficits over a 48-month period. The Alabama PSC gives Alabama Power authority to record a deficit balance in the NDR when costs of storm damage exceed any established reserve balance. Reliability Reserve Accounting Order On June 19, 2025, Alabama Power notified the Alabama PSC of its intent to use a portion of its $131 million reliability reserve balance during 2025. As a result, Alabama Power had usage of the reliability reserve in the amount of $30 million during the third quarter 2025 for reliability-related transmission, distribution, and generation expenses. At September 30, 2025, Alabama Power's reliability reserve balance was $101 million. Nuclear Production Tax Credits Order On October 7, 2025, the Alabama PSC issued an order authorizing Alabama Power to establish a regulatory liability for nuclear PTCs received through its nuclear generating facilities pursuant to Internal Revenue Code §45U for tax years 2024 through 2032. For the 2024 tax year, Alabama Power claimed §45U PTCs on Southern Company's consolidated tax return. The base credit amount of $36 million is included in a regulatory liability. Additionally, Alabama Power claimed the prevailing wage multiplier on its 2024 federal income tax return for a total credit claimed of $180 million. The §45U PTC is available for tax years 2024 to 2032 and is subject to a phase-out. As such, Alabama Power will evaluate annually whether it qualifies for the credit. The §45U PTCs will be deferred as a regulatory liability until the Alabama PSC provides direction on how to apply them for the benefit of customers. The ultimate outcome of this matter cannot be determined at this time. See Note (G) under "Unrecognized Tax Benefits" herein for additional information. Georgia Power 2022 ARP On July 1, 2025, the Georgia PSC approved a settlement agreement among Georgia Power, the staff of the Georgia PSC, and certain intervenors to extend the 2022 ARP for an additional three-year term through December 31, 2028 (ARP Extension). Under the ARP Extension, base rates will not be adjusted in 2026, 2027, or 2028 (ARP Extension Period) except for reasonable and prudent storm damage costs incurred through December 31, 2025, which will be determined in a separate regulatory proceeding. Under the ARP Extension, Georgia Power's retail ROE set point will continue at 10.50% and its equity ratio will continue at 56%. Additionally, the retail ROE range approved by the Georgia PSC in the 2022 ARP, of 9.50% to 11.90%, will continue. The ARP Extension includes, among other things, the following modifications to the 2022 ARP: •Storm damage costs will be included in a separate regulatory proceeding to be filed no sooner than February 1, 2026 and no later than July 1, 2026 to recover the actual reasonable and prudent storm costs incurred through December 31, 2025. Subject to Georgia PSC approval, new rates would be effective approximately 90 days after the filing is made. The Georgia PSC will determine the period over which any such storm damage costs will be recovered. •Amortization of regulatory assets and liabilities in the 2022 ARP, which were subsequently included in current rates through annual compliance filings, will continue through the ARP Extension Period. This includes those regulatory asset and liability balances that were projected to be fully amortized through 2025 or during the ARP Extension Period. •The amounts previously deferred during the 2022 ARP for ITCs and PTCs will be amortized through the ARP Extension Period. The acceleration of amortization during the ARP Extension Period is subject to the Internal Revenue Code normalization rules and other guidance (if any) released by the IRS. Certain amounts of ITCs generated during the ARP Extension Period will be amortized over five years, and additional ITC amounts will be deferred to a regulatory liability during the ARP Extension Period. Sixty percent (60%) of PTC benefits generated (excluding PTCs generated under Internal Revenue Code §45J) during the ARP Extension Period will be credited to income tax expense as generated. The remaining forty percent (40%) will be deferred to a regulatory liability. •The period for depreciation and amortization related to certain generating plants and net book values of retired generating plants will be 13 years effective January 1, 2026. Using the retail ROE range approved by the Georgia PSC in the 2022 ARP, earnings above 11.90% retail ROE will continue to be subject to sharing whereby 40% of earnings above the band would be applied to regulatory assets, 40% would be directly refunded to customers, and the remaining 20% would be retained by Georgia Power. There will be no recovery of any earnings shortfall below 9.50% retail ROE on an actual basis. However, if at any time during the term of the ARP Extension Period, Georgia Power projects that its retail earnings will be less than the lower end of the approved retail ROE range for any calendar year of the ARP Extension Period, it may petition the Georgia PSC for implementation of the Interim Cost Recovery (ICR) tariff to adjust Georgia Power's retail rates to achieve a retail ROE equal to the lower end of the approved retail ROE range. Any ICR tariff would expire at the earlier of January 1, 2029 or the end of the calendar year in which the ICR tariff becomes effective. In lieu of requesting implementation of an ICR tariff, or if the Georgia PSC chooses not to implement the ICR tariff, Georgia Power may file a full base rate case. Except as provided above, Georgia Power will not file a base rate increase while the ARP Extension is in effect. Georgia Power is required to file a general base rate case by July 1, 2028. Integrated Resource Plans On September 4, 2025, the Georgia PSC approved Georgia Power's June 2025 request to certify a Georgia Power-owned battery energy storage facility with a capacity of 200 MWs and a projected COD in 2027. On July 30, 2025, Georgia Power requested certification from the Georgia PSC, for which a final decision is expected to be rendered in December 2025, for the following resources: •As included in the 2022 IRP final order, Georgia Power initiated a request for proposals (RFP) of up to 8,500 MWs of capacity from a variety of resources with projected CODs or delivery commencement dates between 2028 and 2030. The RFP resulted in 18 resources, totaling 7,999 MWs, being selected which consist of four PPAs (including two affiliate PPAs with Southern Power that are subject to approval by the FERC) with capacity totaling 1,195 MWs commencing between 2028 and 2030, three project sites consisting of five Georgia Power-owned combined cycle units with capacity totaling 3,692 MWs and projected CODs commencing between 2029 and 2030, nine Georgia Power-owned battery energy storage facilities with capacity totaling 2,762 MWs and projected CODs commencing between 2028 and 2030, and two Georgia Power-owned battery energy storage facilities with solar with capacity totaling 350 MWs and projected CODs commencing in 2028. •In July 2025, Georgia Power extended 50 MWs of an existing 750-MW affiliate PPA with Mississippi Power for an additional year through December 31, 2029. •Additionally, in July 2025, Georgia Power executed a 20-year non-affiliate PPA for 930 MWs commencing in 2030 and five 25-year non-affiliate PPAs totaling 646 MWs commencing in 2027. •Georgia Power entered into agreements to initiate acquisition of property and construction of a 260-MW Georgia Power-owned battery energy storage facility with a projected COD in 2027 to be paired with an existing non-affiliate solar PPA. The certification requests in June and July 2025 associated with these Georgia Power-owned projects and related transmission investments total approximately $16.7 billion, excluding AFUDC. At September 30, 2025, Georgia Power had recorded approximately $725 million of combined capital costs, excluding AFUDC, for the projects requested for certification. As required by the 2025 IRP decision, Georgia Power filed with the Georgia PSC on September 17, 2025 an updated load forecast to support the certification requests from the RFP of up to 8,500 MWs. The Georgia PSC will determine the necessary generation resources to certify. See "2025 IRP" herein for information regarding the 2025 IRP. The ultimate outcome of these matters cannot be determined at this time. 2025 IRP On July 15, 2025, the Georgia PSC approved Georgia Power's 2025 IRP, as modified by a stipulation among Georgia Power, the staff of the Georgia PSC, and certain intervenors. In the 2025 IRP decision, the Georgia PSC approved the following requests: •Extended operation of Plant Scherer Unit 3 (614 MWs based on 75% ownership) through at least December 31, 2035 and Plant Gaston Units 1 through 4 (500 MWs based on 50% ownership through SEGCO) through December 31, 2034. See Note 7 to the financial statements under "SEGCO" in Item 8 of the Form 10-K for additional information. •Installation of environmental controls and natural gas co-firing at Plant Bowen Units 1 through 4 (3,160 MWs), Plant Scherer Units 1 and 2 (137 MWs based on 8.4% ownership), and Plant Scherer Unit 3 for compliance with both ELG supplemental rules and GHG rules. •Upgrades to Plant McIntosh Units 10 and 11 (1,319 MWs) for a projected 194 MWs of incremental capacity by 2028 and Plant McIntosh Units 1 through 8 (640 MWs) for a projected 74 MWs of incremental capacity by 2033. •Upgrades to Plant Vogtle Units 1 and 2 (1,060 MWs based on 45.7% ownership) for a projected 54 MWs of incremental capacity, some of which could be available as early as 2028. •Investments related to the continued reliable hydro operations of four facilities, as well as the authority to spend up to $25 million to undertake engineering studies related to two additional hydro facilities. •RFP for at least 1,100 MWs of utility scale and distributed generation renewable resources. •Issuance of a capacity RFP to procure resources to meet capacity needs in 2032 and 2033. •Strategic power delivery infrastructure plan necessary to help ensure adequate reliability and serve the projected future load growth expected in Georgia. •Certification of approximately 187 MWs of wholesale capacity associated with Plant Scherer Unit 3 to be placed in retail rate base, some of which will be available beginning in 2026. In addition, the 2025 IRP assumes Plant Bowen Units 1 and 2 will operate through at least the end of 2035. Fuel Cost Recovery On May 14, 2025, Georgia Power submitted an Interim Fuel Rider (IFR) notification and plan informing the Georgia PSC that Georgia Power's under recovered fuel balance accumulated since May 31, 2023 exceeded the IFR threshold of $200 million, established in a Georgia PSC stipulation approved in May 2023. Georgia Power proposed no fuel cost recovery rate change and is required to monitor and report to the Georgia PSC monthly as long as the under recovered fuel balance accumulated since May 31, 2023 is above $200 million. On September 15, 2025, Georgia Power filed its most recent IFR plan and notification which also proposed no fuel cost recovery rate change. At September 30, 2025, Georgia Power's under recovered fuel balance accumulated since May 31, 2023 did not exceed the IFR threshold of $200 million. Georgia Power is scheduled to file its next fuel case no later than February 28, 2026. Nuclear Construction Georgia Power placed Plant Vogtle Units 3 and 4 in service on July 31, 2023 and April 29, 2024, respectively. During the third quarter 2025, following the completion of site demobilization efforts, Southern Nuclear evaluated the remaining contractor obligations and reduced the remaining estimate to complete forecast by approximately $33 million. Accordingly, Georgia Power recorded a pre-tax credit to income of approximately $33 million ($25 million after tax) in the third quarter 2025 to recognize capital costs previously charged to income. Georgia Power's net investment in connection with Plant Vogtle Units 3 and 4 at September 30, 2025 is $10.690 billion, which excludes capitalized AFUDC of approximately $440 million accrued through Unit 4's in-service date. Other Construction At September 30, 2025, Georgia Power had recorded approximately $1.5 billion of combined capital costs, excluding AFUDC, for the projects reflected in the table below. The total certified amounts related to these projects are approximately $2.8 billion, excluding AFUDC. The ultimate outcome of these matters cannot be determined at this time.
Project(*) | Resource | Approximate Nameplate Capacity (MW) | Projected COD | Regulatory Approval
Projects Under Construction at September 30, 2025
McGrau Ford | Battery energy storage | 265 | Fourth quarter 2026 | 2022 IRP
Plant Yates Units 8 through 10 | Combustion turbine | 1,326 | Fourth quarter 2026 through third quarter 2027 | 2023 IRP Update
Various facilities | Battery energy storage | 500 | Second quarter 2026 through fourth quarter 2026 | 2023 IRP Update
(*)Excludes a 200-MW battery energy storage facility which has not incurred significant costs. See "Integrated Resource Plans" herein for additional information. Mississippi Power Performance Evaluation Plan On June 17, 2025, the Mississippi PSC approved Mississippi Power's annual retail PEP filing for 2025, resulting in an annual increase in revenues of approximately 4.0%, or $41 million, primarily due to increases in investment and depreciation. In accordance with the PEP rate schedule, an increase of 2.0% of total retail revenues, or approximately $22 million, became effective with the first billing cycle of April 2025, and the remaining approximately $19 million became effective with the first billing cycle of July 2025. Integrated Resource Plans On July 8, 2025, Mississippi Power extended 50 MWs of an existing 750-MW affiliate PPA with Georgia Power for an additional year through December 31, 2029, subject to approval by the Georgia PSC. The ultimate outcome of this matter cannot be determined at this time. See "Georgia Power – Integrated Resource Plans" herein for additional information. Environmental Compliance Overview Plan On April 1, 2025, the Mississippi PSC approved Mississippi Power's annual ECO Plan filing for 2025, resulting in a $6 million annual increase in revenues effective with the first billing cycle of May 2025. Ad Valorem Tax Adjustment On August 5, 2025, the Mississippi PSC approved Mississippi Power's annual ad valorem tax adjustment filing for 2025, resulting in a $7 million annual increase in revenues effective with the first billing cycle of September 2025. This increase is not expected to have a significant effect on Mississippi Power's net income but will affect operating cash flows. System Restoration Rider On June 17, 2025, the Mississippi PSC approved Mississippi Power's annual SRR filing for 2025, with no change in retail rates. Mississippi Power's minimum annual SRR accrual increased from $12.6 million to $13.5 million and the target property damage reserve balance increased from $75 million to $125 million. Mississippi Power will continue to record a minimum annual accrual until a target property damage reserve balance of $125 million is met. Reliability Reserve Accounting Order On March 17, 2025, Mississippi Power notified the Mississippi PSC of its intent to use a portion of its $57 million reliability reserve balance during 2025, through the annual PEP filing. On June 17, 2025, the Mississippi PSC approved the annual PEP filing which allowed the use of $10.9 million of the reliability reserve balance, which Mississippi Power used for reliability-related generation, transmission, and distribution expenses in the second quarter 2025. See "Performance Evaluation Plan" herein for information regarding approval of the annual PEP filing. Plant Daniel On June 19, 2025, the Florida PSC issued a final order approving the transfer of FP&L's 50% ownership interest in Plant Daniel Units 1 and 2 to Mississippi Power. On July 30, 2025, Mississippi Power completed the acquisition of FP&L's 50% interest in Plant Daniel Units 1 and 2 and, as part of the acquisition, received approximately $36 million from FP&L, which was recorded as a regulatory liability and is being amortized to offset incremental costs as authorized by the Mississippi PSC. Municipal and Rural Associations Tariff On April 3, 2025, the FERC approved a settlement agreement filed by Mississippi Power and Cooperative Energy in December 2024. The settlement agreement provided for (i) a $1 million increase in annual wholesale base revenues and a refund to customers of approximately $4 million, (ii) a rate escalation of 2.5% on an annual basis in periods subsequent to December 31, 2024 and continuing through the end of the shared service agreement on December 31, 2035, and (iii) a waiver of rights by Mississippi Power and Cooperative Energy to file for any changes in non-fuel rates through the end of the term of the shared service agreement. Southern Company Gas Infrastructure Replacement Programs and Capital Projects On March 26, 2025, the Illinois Supreme Court denied Nicor Gas' petition for leave to appeal $14 million of the 2019 Qualifying Infrastructure Plant disallowance. This matter is concluded and had no impact on the current period financial statements. Rate Proceedings On August 12, 2025, Virginia Natural Gas, the Virginia Commission staff, and certain intervenors entered into a stipulation related to Virginia Natural Gas' August 2024 general base rate case filing. The stipulation provides for a $40 million increase in annual base rate revenues, including the recovery of investments under the SAVE program, an ROE of 9.85%, and an equity ratio of 49.35%. Interim rates became effective January 1, 2025, subject to refund, based on Virginia Natural Gas' original requested increase of approximately $63 million. The Virginia Commission is expected to issue an order on the requested increase in the fourth quarter 2025. The ultimate outcome of this matter cannot be determined at this time.

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