NYSE: GPJA

See "The Southern Company System" herein for additional information. Also see Note 15 to the financial statements in Item 8 herein for information regarding recent acquisition and disposition activity. Segment information for the Registrants is included in Note 16 to the financial statements in Item 8 herein.

The Registrants' Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K, and any amendments to those reports are made available on Southern Company's website, free of charge, as soon as reasonably practicable after such material is electronically filed with or furnished to the SEC. Southern Company's internet address is www.southerncompany.com. The information contained on, or available through, Southern Company's internet website is not, and shall not be deemed to be, incorporated by reference into this report.

The Southern Company System

Traditional Electric Operating Companies

The traditional electric operating companies are vertically integrated utilities that own generation, transmission, and distribution facilities. See PROPERTIES – "Electric" in Item 2 herein for additional information on the traditional electric operating companies' generating facilities. Each company's transmission facilities are connected to the respective company's own generating plants and other sources of power (including certain generating plants owned by Southern Power) and are interconnected with the transmission facilities of the other traditional electric operating companies and SEGCO. For information on the state of Georgia's integrated transmission system, see "Territory and Customers Served by the Southern Company System – Traditional Electric Operating Companies and Southern Power" herein.

Agreements in effect with principal neighboring utility systems provide for capacity and energy transactions that may be entered into for reasons related to reliability or economics. Additionally, the traditional electric operating companies have entered into various reliability agreements with certain neighboring utilities, each of which provides for the establishment and periodic review of principles and procedures for planning and operation of generation and transmission facilities, maintenance schedules, load retention programs, emergency operations, and other matters affecting the reliability of bulk power supply. The

I-1

Table of Contents Index to Financial Statements

traditional electric operating companies have joined with other utilities in the Southeast to form the SERC Reliability Corporation (SERC) to augment further the reliability and adequacy of bulk power supply. Through the SERC, the traditional electric operating companies are represented at the North American Electric Reliability Corporation. In 2022, the Southeast Energy Exchange Market (SEEM) began service. SEEM, whose members include the traditional electric operating companies and many of the other electric service providers in the Southeast, is an extension of the existing bilateral market where participants use an automated, intra-hour energy exchange to buy and sell power close to the time the energy is consumed, utilizing available unreserved transmission. Following a remand order issued by the U.S. Court of Appeals for the D.C. Circuit related to the FERC's initial approval of SEEM, on March 14, 2025, the FERC issued a further order affirming its initial approval of the SEEM market platform, subject to a later compliance filing. The FERC accepted the required compliance filing on June 26, 2025. New appeals were filed at the U.S. Court of Appeals for the D.C. Circuit while the FERC considered the court's earlier remand. On January 6, 2026, the FERC issued an order accepting a settlement agreement between SEEM members and petitioners in the ongoing appeal proceedings to resolve all pending appeals, subject to a compliance filing to modify the SEEM agreement in accordance with the settlement. The compliance filing was submitted on February 5, 2026. The pending appeals have been withdrawn in accordance with the settlement, which concludes all pending challenges to SEEM's approval. The ultimate outcome of this matter cannot be determined at this time.

The utility assets of the traditional electric operating companies and certain utility assets of Southern Power Company are operated as a single integrated electric system, or the Southern Company power pool, pursuant to the IIC. Activities under the IIC are administered by SCS, which acts as agent for the traditional electric operating companies and Southern Power Company. The fundamental purpose of the Southern Company power pool is to provide for the coordinated operation of the electric facilities in an effort to achieve the maximum possible economies consistent with the highest practicable reliability of service. Subject to service requirements and other operating limitations, system resources are committed and controlled through the application of centralized economic dispatch. Under the IIC, each traditional electric operating company and Southern Power Company retains its lowest cost energy resources for the benefit of its own customers and delivers any excess energy to the Southern Company power pool for use in serving customers of other traditional electric operating companies or Southern Power Company or for sale by the Southern Company power pool to third parties. The IIC provides for the recovery of specified costs associated with the affiliated operations thereunder, as well as the proportionate sharing of costs and revenues resulting from Southern Company power pool transactions with third parties.

The traditional electric operating companies are projecting a significant increase in demand for electricity sales, largely driven by data centers and other large load customers. Serving the projected increased load demand from these new customers while continuing to serve existing customers safely, reliably, and affordably requires investing in generation, transmission, and distribution systems and pricing sales to these new customers such that the related incremental costs are met with adequate incremental revenues from these new customers. Through the 2022 IRP and the 2023 IRP Update, the Georgia PSC has certified resources totaling approximately 13 GWs, approximately nine GWs of which are new generation and battery energy storage facilities that are being, or are expected to be, constructed by Georgia Power. The certified costs of these Georgia Power projects total $19.5 billion, and these projects are projected to be placed in service through 2030. Since 2023, the traditional electric operating companies have contracted with new data centers and other large load customers covering approximately nine GWs of electric load, with each contract individually representing a maximum annual electric load greater than 100 MWs, that have been signed by the parties and/or reviewed by the state regulatory commissions. These new contracts fully ramp up over several years after commencement of service. Some of these contracts are already in effect. Service under the contracts is expected to begin through 2028. The contracts contain various terms and conditions, such as minimum duration, minimum bill provisions, contribution by the customer to local construction costs, termination payment requirements, and financial security, designed to generate adequate incremental revenues associated with incremental costs to serve these customers.

Southern Power and Southern Linc have secured from the traditional electric operating companies certain services which are furnished in compliance with FERC regulations.

Alabama Power and Georgia Power each have agreements with Southern Nuclear to operate the Southern Company system's nuclear plants, Plants Farley, Hatch, and Vogtle. See "Regulation – Nuclear Regulation" herein for additional information.

Southern Power

Southern Power develops, constructs, acquires, owns, operates, and manages power generation assets, including battery energy storage projects, and sells electricity at market-based rates (under authority from the FERC) in the wholesale market. Southern Power seeks opportunities to execute its strategy to create value through various transactions including acquisitions, dispositions, sales and purchases of partnership interests, development and construction of new generating facilities, and entry into PPAs, primarily with investor-owned utilities, IPPs, municipalities, electric cooperatives, and other load-serving entities, as well as commercial and industrial customers. Southern Power's business activities are not subject to traditional state regulation like the traditional electric operating companies, but the majority of its business activities are subject to regulation by the FERC.

I-2

Table of Contents Index to Financial Statements

For additional information on Southern Power's business activities, see MANAGEMENT'S DISCUSSION AND ANALYSIS – OVERVIEW – "Business Activities" in Item 7 herein.

Southern Power Company directly owns and manages generation assets primarily in the Southeast, which are included in the Southern Company power pool, and has various subsidiaries whose generation assets are not included in the Southern Company power pool. These subsidiaries were created to own, operate, and pursue power generation facilities, either wholly or in partnership with various third parties. At December 31, 2025, Southern Power's generation fleet, which is owned in part with various partners, totaled 12,648 MWs of nameplate capacity in commercial operation (including 5,268 MWs of nameplate capacity owned by its subsidiaries). See "Traditional Electric Operating Companies" herein for additional information on the Southern Company power pool.

A majority of Southern Power's partnerships in renewable facilities allow for the sharing of cash distributions and tax benefits at differing percentages, with Southern Power being the controlling partner and thus consolidating the assets and operations of the partnerships. At December 31, 2025, Southern Power had seven tax equity partnership arrangements where the tax equity investors receive substantially all of the tax benefits from the facilities, including ITCs and PTCs. In addition, Southern Power holds controlling interests in non-tax equity partnerships with its ownership interests primarily ranging from 51% to 66%.

See PROPERTIES – "Electric" in Item 2 herein for additional detail regarding Southern Power's generating facilities and partnership arrangements and Note 15 to the financial statements under "Southern Power" in Item 8 herein for additional information regarding Southern Power's acquisitions, dispositions, construction, and development projects.

Southern Power's electricity sales from natural gas generating facilities are primarily through long-term, fixed-price capacity PPAs with unaffiliated wholesale purchasers as well as with the traditional electric operating companies and consist of two types of agreements. The first type, referred to as a unit or block sale, is a customer purchase from a dedicated plant unit where all or a portion of the generation from that unit is reserved for that customer. Southern Power typically has the ability to serve the unit or block sale customer from an alternate resource. The second type, referred to as requirements service, provides that Southern Power serves the customer's capacity and energy requirements from a combination of the customer's own generating units and from Southern Power resources not dedicated to serve unit or block sales. Southern Power has rights to purchase power provided by the requirements customers' resources when economically viable. Capacity charges that form part of the PPA payments are designed to recover fixed and variable operations and maintenance costs based on dollars-per-kilowatt year and to provide a return on investment. Southern Power has attempted to insulate itself from significant fuel supply, fuel transportation, and electric transmission risks by generally making such risks the responsibility of the counterparties to its PPAs.

Southern Power's electricity sales from solar and wind generating facilities are also primarily through long-term PPAs; however, these solar and wind PPAs do not have a capacity charge and customers either purchase the energy output of a dedicated renewable facility through an energy charge or provide Southern Power a certain fixed price for the electricity sold to the grid. As a result, Southern Power's ability to recover fixed and variable operations and maintenance expenses is dependent upon the level of energy generated from these facilities, which can be impacted by weather conditions, equipment performance, transmission constraints, and other factors. Generally, under the renewable generation PPAs, the purchasing party retains the right to keep or resell the renewable energy credits.

Southern Power actively pursues replacement PPAs prior to the expiration of its current PPAs and anticipates that the revenues attributable to one customer may be replaced by revenues from a new customer; however, the expiration of any of Southern Power's current PPAs without the successful remarketing of a replacement PPA could have a material negative impact on Southern Power's earnings but is not expected to have a material impact on Southern Company's earnings.

Southern Power calculates an investment coverage ratio for its generating assets, including those owned with various partners, based on the ratio of investment under contract to total investment using the respective facilities' net book value (or expected in-service value for facilities under construction) as the investment amount. With the inclusion of investments associated with facilities under construction, as well as other capacity and energy contracts, Southern Power's average investment coverage ratio at December 31, 2025 was 97% through 2030 and 89% through 2035, with an average remaining contract duration of approximately 12 years. For the year ended December 31, 2025, approximately 63% of contracted MWs were with AAA to A- or equivalent rated counterparties, 31% were with BBB+ to BBB- or equivalent rated counterparties, and 4% were with unrated entities that either have ratemaking authority or have posted collateral to cover potential credit exposure.

Southern Power's future earnings will depend on the parameters of the wholesale market and the efficient operation of its wholesale generating assets; Southern Power's ability to execute its growth strategy through the development, construction, or acquisition of generating facilities and other energy projects while containing costs; regulatory matters; customer creditworthiness; total electric generating capacity available in Southern Power's market areas; Southern Power's ability to successfully remarket capacity as current contracts expire; renewable portfolio standards; continued availability of federal and

I-3

Table of Contents Index to Financial Statements

state ITCs and PTCs under current and future tax legislation and U.S. Treasury guidance; transmission constraints; cost of generation from units within the Southern Company power pool; and operational limitations.

Southern Company Gas

Southern Company Gas is an energy services holding company whose primary business is the distribution of natural gas through the natural gas distribution utilities. Southern Company Gas is also involved in several other businesses that are complementary to the distribution of natural gas, including gas pipeline investments and gas marketing services. Southern Company Gas also has an "all other" non-reportable segment that includes segments below the quantitative threshold for separate disclosure.

Gas distribution operations, the largest segment of Southern Company Gas' business, operates, constructs, and maintains approximately 77,900 miles of natural gas pipelines and 14 storage facilities, with total capacity of 157 Bcf, to provide natural gas to residential, commercial, and industrial customers. Gas distribution operations serves approximately 4.4 million customers across Illinois, Georgia, Virginia, and Tennessee.

Gas pipeline investments primarily consists of joint ventures in natural gas pipeline investments including a 50% interest in SNG and a 50% joint ownership interest in the Dalton Pipeline. These natural gas pipelines enable the provision of diverse sources of natural gas supplies to the customers of Southern Company Gas. SNG, the largest natural gas pipeline investment, is the owner of a 7,000-mile pipeline connecting natural gas supply basins in Texas, Louisiana, Mississippi, and Alabama to markets in Louisiana, Mississippi, Alabama, Florida, Georgia, South Carolina, and Tennessee. SNG is developing a proposed pipeline project, designed to meet customer demand by increasing SNG's existing pipeline capacity by approximately 1.3 billion cubic feet per day, which the operator of the joint venture anticipates will be completed by 2029. The ultimate outcome of this matter cannot be determined at this time. See MANAGEMENT'S DISCUSSION AND ANALYSIS – FUTURE EARNINGS POTENTIAL – "Construction Programs" in Item 7 herein for additional information.

Gas marketing services is comprised of SouthStar, which serves approximately 677,000 natural gas commodity customers, markets gas to residential, commercial, and industrial customers and offers energy-related products that provide natural gas price stability and utility bill management in competitive markets or markets that provide for customer choice.

Construction Programs

The subsidiary companies of Southern Company are engaged in continuous construction programs, including capital expenditures to accommodate existing and estimated future loads on their respective systems and to comply with environmental laws and regulations, as applicable. In 2026, the Southern Company system's construction program is expected to be apportioned approximately as follows:

Southern Company

system(a)(b)(c)(d)

Alabama

Power(c)

Georgia

Power(d)

Mississippi

Power(a)

(in billions)

New generation$3.7 $0.1 $3.6 $—

Environmental compliance(e)
0.2 0.1 0.1 —

Generation maintenance1.4 0.3 1.0 0.1

Transmission3.2 0.4 2.6 0.2

Distribution2.0 0.5 1.4 0.1

Nuclear fuel0.3 0.1 0.2 —

General plant1.8 0.5 1.2 0.1

12.6 2.0 10.1 0.4

Southern Power(f)
0.9

Southern Company Gas(g)
2.2

Other subsidiaries0.2

Total(a)
$15.9 $2.0 $10.1 $0.4

(a)Totals may not add due to rounding.

(b)Includes the Subsidiary Registrants, as well as other subsidiaries.

(c)Excludes $38 million related to Alabama Power's decision to convert Plant Barry Unit 5 from coal to natural gas. See MANAGEMENT'S DISCUSSION AND ANALYSIS – FUTURE EARNINGS POTENTIAL – "Environmental Matters – Environmental Laws and Regulations – Water Quality" in Item 7 herein and Note 2 to the financial statements under "Alabama Power – Environmental Accounting Order" in Item 8 herein for additional information.

I-4

Table of Contents Index to Financial Statements

(d)Includes expenditures of approximately $3.1 billion for construction projects and related transmission investments approved in conjunction with the 2022 IRP, the 2023 IRP Update, and the 2025 IRP. See Note 2 to the financial statements under "Georgia Power – Integrated Resource Plans" and " – Other Construction" in Item 8 herein for additional information.

(e)Reflects cost estimates for environmental laws and regulations. These estimated expenditures do not include compliance costs associated with the regulation of GHG emissions or costs associated with closure and monitoring of surface impoundments and landfills in accordance with the CCR Rule and the related state rules. See MANAGEMENT'S DISCUSSION AND ANALYSIS – FUTURE EARNINGS POTENTIAL – "Environmental Matters" and – FINANCIAL CONDITION AND LIQUIDITY – "Cash Requirements" in Item 7 herein for additional information. No material capital expenditures are expected for non-environmental government regulations.

(f)Includes $40 million and $0.7 billion related to the Millers Branch solar project and wind repowering projects, respectively. Does not include approximately $0.8 billion for planned acquisitions and placeholder growth, which may vary materially due to market opportunities and Southern Power's ability to execute its growth strategy. See Note 15 to the financial statements under "Southern Power" in Item 8 herein for additional information regarding the Millers Branch solar project and the wind repowering projects.

(g)Includes costs for ongoing capital projects associated with infrastructure improvement programs for certain natural gas distribution utilities that have been previously approved by their applicable state regulatory agencies. See Note 2 to the financial statements under "Southern Company Gas" in Item 8 herein for additional information. Also includes gas pipeline investment of approximately $0.3 billion. See MANAGEMENT'S DISCUSSION AND ANALYSIS – FUTURE EARNINGS POTENTIAL – "Construction Programs" in Item 7 herein for information regarding this project.

The construction programs are subject to periodic review and revision, and actual construction costs may vary from these estimates because of numerous factors.

The traditional electric operating companies also anticipate continued expenditures associated with closure and monitoring of surface impoundments and landfills in accordance with the CCR Rule and the related state rules, which are reflected in the applicable Registrants' ARO liabilities. Estimated costs for 2026 total $653 million for Southern Company, primarily consisting of $256 million for Alabama Power, $360 million for Georgia Power, and $18 million for Mississippi Power.

See MANAGEMENT'S DISCUSSION AND ANALYSIS – FINANCIAL CONDITION AND LIQUIDITY – "Cash Requirements" in Item 7 herein for additional information, including estimated expenditures for construction, environmental compliance, and closure and monitoring of surface impoundments and landfills for the years 2027 through 2030.

Also see MANAGEMENT'S DISCUSSION AND ANALYSIS – FUTURE EARNINGS POTENTIAL – "Environmental Matters" in Item 7 herein for additional information with respect to certain existing and proposed environmental requirements and PROPERTIES – "Electric – Jointly-Owned Facilities" and – "Natural Gas – Jointly-Owned Properties" in Item 2 herein and Note 5 to the financial statements under "Joint Ownership Agreements" in Item 8 herein for additional information concerning the Registrants' joint ownership of certain facilities.

Financing Programs

See MANAGEMENT'S DISCUSSION AND ANALYSIS – FINANCIAL CONDITION AND LIQUIDITY in Item 7 herein and Note 8 to the financial statements in Item 8 herein for information concerning financing programs.

Fuel Supply

Electric

The traditional electric operating companies' and SEGCO's supply of electricity is primarily fueled by natural gas and coal, as well as nuclear for Alabama Power and Georgia Power. Southern Power's supply of electricity is primarily fueled by natural gas. See MANAGEMENT'S DISCUSSION AND ANALYSIS – RESULTS OF OPERATIONS – "Southern Company – Electricity Business – Fuel and Purchased Power Expenses" and MANAGEMENT'S DISCUSSION AND ANALYSIS – RESULTS OF OPERATIONS under "Fuel and Purchased Power Expenses" for each of the traditional electric operating companies in Item 7 herein for information regarding the electricity generated and the average cost of fuel in cents per net KWH generated for the years 2024 and 2025.

SCS, acting on behalf of the traditional electric operating companies and Southern Power Company, has agreements in place for the natural gas burn requirements of the Southern Company system. For 2026, SCS has contracted for 644 Bcf of natural gas supply under agreements with remaining terms up to nine years. In addition to natural gas supply, SCS has contracts in place for both firm natural gas transportation and storage. Management believes these contracts provide sufficient natural gas supplies, transportation, and storage to ensure normal operations of the Southern Company system's natural gas generating units. See "Natural Gas" herein for information on the natural gas market.

The traditional electric operating companies have agreements in place from which they expect to receive substantially all of their 2026 coal burn requirements. These agreements have terms ranging between one and five years. Fuel procurement specifications, emission allowances, environmental control systems, and fuel changes have allowed the traditional electric operating companies to remain within limits set by applicable environmental regulations. As new environmental regulations are proposed that impact the utilization of coal, the traditional electric operating companies' fuel mix will be monitored to help ensure compliance with applicable laws and regulations. Southern Company and the traditional electric operating companies

I-5

Table of Contents Index to Financial Statements

will continue to evaluate the need to purchase additional emissions allowances, the timing of capital expenditures for environmental control equipment, and potential unit retirements and replacements or extension of retirement dates of certain fossil fuel plants. While none of Southern Company's subsidiaries are currently subject to renewable portfolio standards or similar requirements, management of the traditional electric operating companies is working with applicable regulators through their IRP processes to continue the generating fleet transition in a manner responsible to customers, communities, employees, and other stakeholders. See MANAGEMENT'S DISCUSSION AND ANALYSIS – FUTURE EARNINGS POTENTIAL – "Environmental Matters" in Item 7 herein and Note 2 to the financial statements under "Alabama Power – Environmental Accounting Order," "Georgia Power – Integrated Resource Plans," and "Mississippi Power – Integrated Resource Plans" in Item 8 herein for additional information, including the Southern Company system's electric generating mix and plans to retire or convert to natural gas certain coal-fired generating capacity.

Alabama Power and Georgia Power have multiple contracts covering their nuclear fuel needs for uranium, conversion services, enrichment services, and fuel fabrication with remaining terms up to 10 years. Management believes suppliers have sufficient nuclear fuel production capability to permit normal operation of the Southern Company system's nuclear generating units. Alabama Power and Georgia Power also have contracts with the United States, acting through the DOE, that provide for the permanent disposal of spent nuclear fuel. The DOE failed to begin disposing of spent fuel in 1998, as required by the contracts, and Alabama Power and Georgia Power have pursued legal remedies against the government for breach of contract. See Note 3 to the financial statements under "Nuclear Fuel Disposal Costs" in Item 8 herein for additional information.

Changes in fuel prices to the traditional electric operating companies are generally reflected in fuel adjustment clauses contained in rate schedules. See "Rate Matters – Rate Structure and Cost Recovery Plans" herein for additional information. Southern Power's natural gas PPAs generally provide that the counterparty is responsible for substantially all of the cost of fuel.

Natural Gas

Natural gas remains a volatile commodity. Slight supply and demand imbalances can quickly result in significant price moves both up and down. These price movements may be short-lived, but the impacts can be pronounced. Natural gas supplies have continued to grow; however, this growth has been accompanied by LNG export growth. Forward curves project prices will remain in the mid- to high-$3 per mmBtu range through 2030; however, short-term price volatility is expected and future prices could be materially impacted by various factors, including unexpected geopolitical events as well as government policies related to natural gas and energy, including infrastructure development, production, and exports.

Southern Company Gas' procurement plans for natural gas supply and transportation to serve regulated utility customers are reviewed and approved by the regulatory agencies in the states where it operates. Southern Company Gas purchases natural gas supplies in the open market by contracting with producers and marketers and, for Atlanta Gas Light and Chattanooga Gas, under asset management agreements approved by the applicable state regulatory agency. Southern Company Gas also contracts for transportation and storage services from interstate pipelines that are regulated by the FERC. When firm pipeline services are temporarily not needed, Southern Company Gas may release the services in the secondary market under FERC-approved capacity release provisions or utilize asset management arrangements, thereby reducing the net cost of natural gas charged to customers for most of the natural gas distribution utilities. Peak-use requirements are met through utilization of company-owned storage facilities, pipeline transportation capacity, purchased storage services, peaking facilities, and other supply sources, arranged by either transportation customers or Southern Company Gas.

With the exception of Atlanta Gas Light, the natural gas distribution utilities are authorized by the relevant regulatory agencies in the states in which they serve to use natural gas cost recovery mechanisms that adjust rates to reflect changes in the wholesale cost of natural gas and ensure recovery of all costs prudently incurred in purchasing natural gas for customers. See Note 2 to the financial statements under "Southern Company Gas – Natural Gas Cost Recovery" in Item 8 herein for additional information.

Territory and Customers Served by the Southern Company System

Traditional Electric Operating Companies and Southern Power

The territory in which the traditional electric operating companies provide retail electric service comprises most of the states of Alabama and Georgia, together with southeastern Mississippi. In this territory there are non-affiliated electric distribution systems that obtain some or all of their power requirements either directly or indirectly from the traditional electric operating companies. As of December 31, 2025, the territory had an area of approximately 116,000 square miles and an estimated population of approximately 17 million. Southern Power sells wholesale electricity at market-based rates across various U.S. utility markets, primarily to investor-owned utilities, IPPs, municipalities, and other load-serving entities, as well as commercial and industrial customers.

I-6

Table of Contents Index to Financial Statements

Alabama Power is engaged, within the state of Alabama, in the generation, transmission, distribution, and purchase of electricity and the sale of electric service, at retail in approximately 400 cities and towns (including Anniston, Birmingham, Gadsden, Mobile, Montgomery, and Tuscaloosa), as well as in rural areas, and at wholesale to three rural distributing municipal and cooperative associations. In addition, Alabama Power markets and sells outdoor lighting services and other customer-focused utility services. As of December 31, 2025, Alabama Power's sales contract with AMEA expired, thus eliminating wholesale sales to 11 municipally-owned electric distribution systems previously served indirectly through sales to AMEA.

Georgia Power is engaged in the generation, transmission, distribution, and purchase of electricity and the sale of electric service within the state of Georgia, at retail in over 530 cities and towns (including Athens, Atlanta, Augusta, Columbus, Macon, Rome, and Savannah), as well as in rural areas, and at wholesale to OPC, MEAG Power, Dalton, various EMCs, and non-affiliated utilities. Georgia Power also markets and sells outdoor lighting services and other customer-focused utility services.

Mississippi Power is engaged in the generation, transmission, distribution, and purchase of electricity and the sale of electric service within 23 counties in southeastern Mississippi, at retail in 123 communities (including Biloxi, Gulfport, Hattiesburg, Laurel, Meridian, and Pascagoula), as well as in rural areas, and at wholesale to one municipality, six rural electric distribution cooperative associations, and one generating and transmitting cooperative.

The following table provides the number of retail customers served by customer classification for the traditional electric operating companies at December 31, 2025:

Alabama PowerGeorgia Power
Mississippi Power(a)

Total(b)

(in thousands)

Residential1,347 2,480 158 3,986

Commercial209 333 34 576

Industrial6 11 — 17

Other1 10 — 10

Total(b)
1,563 2,834 193 4,590

(a)Includes 421 industrial retail customers and 104 other retail customers.

(b)Totals may not add due to rounding.

For information relating to KWH sales by customer classification for the traditional electric operating companies, see MANAGEMENT'S DISCUSSION AND ANALYSIS – RESULTS OF OPERATIONS in Item 7 herein. Also, for information relating to the sources of revenues for Southern Company, each traditional electric operating company, and Southern Power, see Item 7 herein and Note 1 to the financial statements under "Revenues – Traditional Electric Operating Companies" and " – Southern Power" and Note 4 to the financial statements in Item 8 herein.

As of December 31, 2025, there were 62 electric cooperative distribution systems operating in the territories in which the traditional electric operating companies provide electric service at retail or wholesale.

PowerSouth is a generating and transmitting cooperative selling power to several distributing cooperatives, municipal systems, and other customers in south Alabama. As of December 31, 2025, PowerSouth owned generating units with more than 2,300 MWs of nameplate capacity, including an undivided 8.16% ownership interest in Alabama Power's Plant Miller Units 1 and 2. See PROPERTIES – "Electric – Jointly-Owned Facilities" in Item 2 herein and Note 5 to the financial statements under "Joint Ownership Agreements" in Item 8 herein for additional information.

In accordance with an agreement executed in 2021, Alabama Power began providing approximately 100 MWs of year-round capacity service to PowerSouth on February 1, 2024.

In 2021, Alabama Power and PowerSouth began operations under a coordinated planning and operations agreement, with a minimum term of 10 years. The agreement includes combined operations (including joint commitment and dispatch) and real-time energy sales and purchases and is expected to create energy cost savings and enhanced system reliability for both parties. Projected revenues are expected to offset any increased administrative costs incurred by Alabama Power. Under the agreement, Alabama Power has the right to participate in a portion of PowerSouth's future incremental load growth.

Alabama Power also has a separate agreement with PowerSouth involving interconnection between their systems. The delivery of capacity and energy from PowerSouth to certain distributing cooperatives in the service territory of Alabama Power is governed by the Southern Company/PowerSouth Network Transmission Service Agreement. The rates for this service to PowerSouth are on file with the FERC.

OPC is an EMC owned by its 38 retail electric distribution cooperatives, which provide retail electric service to customers in Georgia. OPC provides wholesale electric power to its members through its generation assets, some of which are jointly owned

I-7

Table of Contents Index to Financial Statements

with Georgia Power, and power purchased from other suppliers. OPC and the 38 retail electric distribution cooperatives are members of Georgia Transmission Corporation, an EMC (GTC), which provides transmission services to its members and third parties. See PROPERTIES – "Electric – Jointly-Owned Facilities" in Item 2 herein and Note 5 to the financial statements under "Joint Ownership Agreements" in Item 8 herein for additional information regarding Georgia Power's jointly-owned facilities.

Mississippi Power has an interchange agreement with Cooperative Energy, a generating and transmitting cooperative, pursuant to which various services are provided. Cooperative Energy also has a 10-year network integration transmission service agreement with SCS for transmission service to certain delivery points on Mississippi Power's transmission system through March 31, 2031. See Note 2 to the financial statements under "Mississippi Power – Municipal and Rural Associations Tariff" in Item 8 herein for information on a separate shared service agreement between Mississippi Power and Cooperative Energy.

As of December 31, 2025, there were 72 municipally-owned electric distribution systems operating in the territory in which the traditional electric operating companies provide electric service at retail or wholesale.

As of December 31, 2025, 48 municipally-owned electric distribution systems and one county-owned system received their requirements through MEAG Power. MEAG Power serves these requirements from self-owned generation facilities, some of which are jointly-owned with Georgia Power, and purchases from other resources. MEAG Power also has a pseudo scheduling and services agreement with Georgia Power. Dalton serves its requirements from self-owned generation facilities, some of which are jointly-owned with Georgia Power, and through purchases from Southern Power through a service agreement. See PROPERTIES – "Electric – Jointly-Owned Facilities" in Item 2 herein and Note 5 to the financial statements under "Joint Ownership Agreements" in Item 8 herein for additional information.

Georgia Power has entered into substantially similar agreements with GTC, MEAG Power, and Dalton providing for the establishment of an integrated transmission system to carry the power and energy of all parties. The agreements require an investment by each party in the integrated transmission system in proportion to its respective share of the aggregate system load. See PROPERTIES – "Electric – Jointly-Owned Facilities" in Item 2 herein for additional information.

Southern Power has PPAs with Georgia Power, investor-owned utilities, IPPs, municipalities, electric cooperatives, and other load-serving entities, as well as commercial and industrial customers. See "The Southern Company System – Southern Power" herein and MANAGEMENT'S DISCUSSION AND ANALYSIS – FUTURE EARNINGS POTENTIAL – "Southern Power's Power Sales Agreements" in Item 7 herein for additional information.

SCS, acting on behalf of the traditional electric operating companies, also has a contract with SEPA providing for the use of the traditional electric operating companies' facilities at government expense to deliver to certain cooperatives and municipalities, entitled by federal statute to preference in the purchase of power from SEPA, quantities of power equivalent to the amounts of power allocated to them by SEPA from certain U.S. government hydroelectric projects.

Southern Company Gas

Southern Company Gas is engaged in the distribution of natural gas in four states through the natural gas distribution utilities. The natural gas distribution utilities construct, manage, and maintain intrastate natural gas pipelines and distribution facilities. Details of the natural gas distribution utilities at December 31, 2025 are as follows:

UtilityStateNumber of customersApproximate miles of pipe

(in thousands)

Nicor GasIllinois2,294 33.8

Atlanta Gas LightGeorgia1,733 36.4

Virginia Natural GasVirginia316 5.9

Chattanooga GasTennessee73 1.8

Total4,416 77.9

For information relating to the sources of revenue for Southern Company Gas, see Item 7 herein and Note 1 to the financial statements under "Revenues – Southern Company Gas" and Note 4 to the financial statements in Item 8 herein.

Competition

Electric

The electric utility industry in the United States is continuing to evolve as a result of regulatory, projected demand requirements, and competitive factors. The competition for retail energy sales among competing suppliers of energy is influenced by various factors, including price, availability, technological advancements, service, and reliability. These factors are, in turn, affected by, among other influences, regulatory, political, and environmental considerations, taxation, and supply.

I-8

Table of Contents Index to Financial Statements

The retail service rights of all electric suppliers in the state of Georgia are regulated by the Territorial Electric Service Act of 1973. Pursuant to standards set forth in this Act, the Georgia PSC has assigned substantially all of the land area in the state to a supplier. Notwithstanding such assignments, this Act provides that any new customer locating outside of 1973 municipal limits and having a connected load of at least 900 KWs may exercise a one-time choice for the life of the premises to receive electric service from the supplier of its choice.

Pursuant to the 1956 Utility Act, the Mississippi PSC issued "Grandfather Certificates" of public convenience and necessity to Mississippi Power and to six distribution rural cooperatives operating in southeastern Mississippi, then served in whole or in part by Mississippi Power, authorizing them to distribute electricity in certain specified geographically described areas of the state. The six cooperatives serve approximately 325,000 retail customers in a certificated area of approximately 10,300 square miles. In areas included in a "Grandfather Certificate," the utility holding such certificate may extend or maintain its electric system subject to certain regulatory approvals; extensions of facilities by such utility, or extensions of facilities into that area by other utilities, may not be made unless the Mississippi PSC grants a CPCN. Areas included in a CPCN that are subsequently annexed to municipalities may continue to be served by the holder of the CPCN, irrespective of whether it has a franchise in the annexing municipality. On the other hand, the holder of the municipal franchise may not extend service into such newly annexed area without authorization by the Mississippi PSC.

Generally, the traditional electric operating companies have experienced, and expect to continue to experience, competition in their respective retail service territories in varying degrees from the development and deployment of alternative energy sources such as self-generation (as described below) and distributed generation technologies, as well as other factors. Further technological advancements or the implementation of policies in support of alternative energy sources may result in further competition.

Southern Power competes with investor-owned utilities, IPPs, and others for wholesale energy sales across various U.S. utility markets. The needs of these markets are driven by the demands of end users and the generation available. Southern Power's success in wholesale energy sales is influenced by various factors including reliability and availability of Southern Power's plants, availability of transmission to serve the demand, price, and Southern Power's ability to contain costs.

As of December 31, 2025, Alabama Power had cogeneration contracts in effect with seven industrial customers. Under the terms of these contracts, Alabama Power purchases excess energy generated by such companies. During 2025, Alabama Power purchased approximately 83 million KWHs from such companies. The related costs were immaterial.

As of December 31, 2025, Georgia Power had contracts in effect to purchase alternative energy generation from 40 IPPs within the state of Georgia. During 2025, Georgia Power purchased 8.2 billion KWHs from such companies at a cost of $363 million. Georgia Power also has PPAs for electricity at cogeneration facilities with six industrial customers. Payments are subject to reductions for failure to meet minimum capacity output. During 2025, Georgia Power purchased 533 million KWHs at a cost of $50 million from these facilities.

As of December 31, 2025, Mississippi Power had a cogeneration agreement in effect with one of its industrial customers. Under the terms of this contract, Mississippi Power purchases any excess generation. During 2025, Mississippi Power did not make any such purchases.

Natural Gas

Southern Company Gas' natural gas distribution utilities do not compete with other distributors of natural gas in their exclusive franchise territories but face competition from other energy products. Their principal competitors are electric utilities and fuel oil and propane providers serving the residential, commercial, and industrial markets in their service areas for customers who are considering switching to or from a natural gas appliance.

Competition for heating as well as general household and small commercial energy needs generally occurs at the initial installation phase when the customer or builder makes decisions as to which types of equipment to install. Customers generally use the chosen energy source for the life of the equipment.

Customer demand for natural gas could be affected by numerous factors, including:

•changes in the availability or price of natural gas and other forms of energy;

•general economic conditions;

•energy conservation, including state-supported energy efficiency programs;

•legislation and regulations, including certain bans on the use of natural gas in new or existing construction and electrification initiatives;

•the cost and capability to convert from natural gas to alternative energy products; and

•technological or regulatory changes resulting in displacement or replacement of natural gas appliances.

I-9

Table of Contents Index to Financial Statements

Southern Company Gas has natural gas-related programs that generally emphasize natural gas as the fuel of choice for customers and seek to expand the use of natural gas through a variety of promotional activities. In addition, Southern Company Gas partners with third-party entities to market the benefits of natural gas appliances.

Seasonality and Demand

The demand for electric power and natural gas supply is affected by seasonal differences in the weather. During normal weather conditions, the Southern Company system's electric power sales peak during both the summer and winter. In most of the areas Southern Company Gas serves, natural gas demand peaks during the winter. As a result, the overall operating results of the Registrants in the future may fluctuate substantially on a seasonal basis. In addition, the Subsidiary Registrants have historically sold less power and natural gas when weather conditions are milder.

See MANAGEMENT'S DISCUSSION AND ANALYSIS – FUTURE EARNINGS POTENTIAL – "General" and – RESULTS OF OPERATIONS – "Southern Company Gas" in Item 7 herein for information regarding trends in market demand for electricity and natural gas and the impact of seasonality on Southern Company Gas' business, respectively.

Regulation

States

The traditional electric operating companies and the natural gas distribution utilities are subject to the jurisdiction of their respective state PSCs or applicable state regulatory agencies. These regulatory bodies have broad powers of supervision and regulation over public utilities operating in the respective states, including their rates, service regulations, sales of securities (except for the Mississippi PSC), and, in the cases of the Georgia PSC and the Mississippi PSC, in part, retail service territories. See "Territory and Customers Served by the Southern Company System" and "Rate Matters" herein for additional information.

Federal Power Act

The traditional electric operating companies, Southern Power Company and certain of its generation subsidiaries, and SEGCO are all public utilities engaged in wholesale sales of energy in interstate commerce and, therefore, are subject to the rate jurisdiction of the FERC under the Federal Power Act. In addition, the traditional electric operating companies and SEGCO are subject to the financial and accounting jurisdiction of the FERC under the Federal Power Act. The FERC must approve certain financings and allows an "at cost standard" for services rendered by system service companies such as SCS and Southern Nuclear. The FERC is also authorized to establish regional reliability organizations which enforce reliability standards, address impediments to the construction of transmission, and prohibit manipulative energy trading practices.

Alabama Power and Georgia Power are also subject to the provisions of the Federal Power Act or the earlier Federal Water Power Act applicable to licensees with respect to their hydroelectric developments. As of December 31, 2025, among the hydroelectric projects subject to licensing by the FERC are 14 existing Alabama Power generating stations having an aggregate installed capacity of 1.7 million KWs and 15 existing Georgia Power generating stations and one generating station partially owned by Georgia Power, with a combined aggregate installed capacity of 1.1 million KWs.

In 2013, the FERC issued a new 30-year license to Alabama Power for Alabama Power's seven hydroelectric developments on the Coosa River (Weiss, Henry, Logan Martin, Lay, Mitchell, Jordan, and Bouldin). Alabama Power filed a petition requesting rehearing of the FERC order granting the relicense seeking revisions to several conditions of the license. In 2016, the FERC issued an order granting in part and denying in part Alabama Power's rehearing request. American Rivers and Alabama Rivers Alliance also filed multiple appeals of the FERC's 2013 order for the new 30-year license, and, in 2018, the U.S. Court of Appeals for the D.C. Circuit vacated the order and remanded the proceeding to the FERC. Alabama Power continues to operate the Coosa River developments under annual licenses issued by the FERC.

In 2021, Alabama Power filed an application with the FERC to relicense the Harris Dam project on the Tallapoosa River. The original Harris Dam project license expired on November 30, 2023, and, in December 2023, the FERC issued an annual license for the continued operation of the Harris Dam project. The Harris Dam project will operate under annual licenses until a new long-term license is issued, which is expected by the fourth quarter 2026.

In 2018, Georgia Power filed applications to surrender the Langdale and Riverview hydroelectric projects on the Chattahoochee River upon their license expirations on December 31, 2023, as they were inoperable by 2009. Georgia Power is currently awaiting the FERC surrender order, which is expected to include dam removal obligations and other post-dam removal activities such as monitoring and riverbank restoration activities.

In September 2024, Georgia Power received a new 40-year FERC license for the Lloyd Shoals project on the Ocmulgee River.

Georgia Power and OPC have a license, expiring on December 31, 2026, for the Rocky Mountain project, a pure pumped storage facility of 903,000 KW installed capacity. In December 2024, OPC, as an agent for co-licensees of the project, filed an

I-10

Table of Contents Index to Financial Statements

application with the FERC to relicense the project. See PROPERTIES – "Electric – Jointly-Owned Facilities" in Item 2 herein for additional information.

Licenses for all projects, excluding those discussed above, expire in the years 2034-2066 for Alabama Power's projects and in the years 2034-2064 for Georgia Power's projects.

Upon or after the expiration of each license, the U.S. government, by act of Congress, may take over the project or the FERC may relicense the project either to the original licensee or to a new licensee. In the event of takeover or relicensing to another, the original licensee is to be compensated in accordance with the provisions of the Federal Power Act, such compensation to reflect the net investment of the licensee in the project, not in excess of the fair value of the property, plus reasonable damages to other property of the licensee resulting from the severance therefrom of the property. The FERC may grant relicenses subject to certain requirements that could result in additional costs.

The ultimate outcome of these matters cannot be determined at this time.

Nuclear Regulation

Alabama Power, Georgia Power, and Southern Nuclear are subject to regulation by the NRC. The NRC is responsible for licensing and regulating nuclear facilities and materials and for conducting research in support of the licensing and regulatory process, as mandated by the Atomic Energy Act of 1954, as amended; the Energy Reorganization Act of 1974, as amended; and the Nuclear Nonproliferation Act of 1978, as amended; and in accordance with the National Environmental Policy Act of 1969, as amended, and other applicable statutes. These responsibilities also include protecting public health and safety, protecting the environment, protecting and safeguarding nuclear materials and nuclear power plants in the interest of national security, and assuring conformity with antitrust laws.

The NRC licenses for Georgia Power's Plant Hatch Units 1 and 2 expire in 2034 and 2038, respectively. On May 15, 2025, Southern Nuclear submitted a subsequent license renewal application to the NRC seeking to renew both units' operating licenses for an additional 20 years (through 2054 and 2058 for Units 1 and 2, respectively). The NRC's decision on this application is anticipated by the end of the second quarter 2026.

The NRC licenses for Alabama Power's Plant Farley Units 1 and 2 expire in 2037 and 2041, respectively. Southern Nuclear has notified the NRC of its intent to seek to renew the plant's licenses for an additional 20 years (through 2057 and 2061 for Units 1 and 2, respectively). The subsequent license renewal application is projected to be submitted by the second quarter 2027.

The NRC licenses for Georgia Power's Plant Vogtle Units 1, 2, 3, and 4 expire in 2047, 2049, 2062, and 2063, respectively.

See Notes 3 and 6 to the financial statements under "Nuclear Insurance" and "Nuclear Decommissioning," respectively, in Item 8 herein for additional information.

Environmental Laws and Regulations

See "Construction Programs" herein, MANAGEMENT'S DISCUSSION AND ANALYSIS – FUTURE EARNINGS POTENTIAL – "Environmental Matters" in Item 7 herein, and Note 3 to the financial statements under "Environmental Remediation" and Note 6 to the financial statements in Item 8 herein for information concerning environmental laws and regulations impacting the Registrants.

Rate Matters

Rate Structure and Cost Recovery Plans

Electric

The rates and service regulations of the traditional electric operating companies are uniform for each class of service throughout their respective retail service territories. Rates for residential electric service are generally of the block type based upon KWHs used and include minimum charges. Residential and other rates contain separate customer charges. Rates for commercial service are also of the block type and, for large customers, the billing demand is generally used to determine capacity and minimum bill charges. These large customers' rates are generally based upon usage by the customer and include rates with special features to encourage off-peak usage. Additionally, Alabama Power and Mississippi Power are generally allowed by their respective state PSCs to negotiate the terms and cost of service to large customers, subject to final state PSC approval.

The traditional electric operating companies recover certain costs through a variety of forward-looking, cost-based rate mechanisms. Fuel and net purchased energy costs are recovered through specific fuel cost recovery provisions. These fuel cost recovery provisions are adjusted to reflect increases or decreases in such costs as needed or on schedules as required by the respective PSCs. Approved compliance, storm damage, and certain other costs are recovered at Alabama Power and Mississippi Power through specific cost recovery mechanisms approved by their respective PSCs. Certain similar costs at Georgia Power

I-11

Table of Contents Index to Financial Statements

are recovered through various base rate tariffs as approved by the Georgia PSC. Costs not recovered through specific cost recovery mechanisms are recovered at Alabama Power and Mississippi Power through annual, formulaic cost recovery proceedings and at Georgia Power through periodic base rate proceedings.

See Note 2 to the financial statements in Item 8 herein for a discussion of rate matters and certain cost recovery mechanisms. Also see "Integrated Resource Planning" herein for additional information.

The traditional electric operating companies and Southern Power Company and certain of its generation subsidiaries are authorized by the FERC to sell power to non-affiliates, including short-term opportunity sales, at market-based prices. Specific FERC approval must be obtained with respect to a market-based contract with an affiliate.

Mississippi Power provides service under long-term contracts with rural electric cooperative associations and a municipality located in southeastern Mississippi which are subject to regulation by the FERC. The contracts with these wholesale customers represented 12.9% of Mississippi Power's total operating revenues in 2025.

Natural Gas

Southern Company Gas' natural gas distribution utilities are subject to regulation and oversight by their respective state regulatory agencies. Rates charged to customers vary according to customer class (residential, commercial, or industrial) and rate jurisdiction. These agencies approve rates designed to provide the opportunity to generate revenues to recover all prudently-incurred costs, including a return on rate base sufficient to pay interest on debt and provide a reasonable ROE.

With the exception of Atlanta Gas Light, the earnings of the natural gas distribution utilities can be affected by customer consumption patterns that are largely a function of price levels for natural gas and general economic conditions that may impact customers' ability to pay for natural gas consumed. The natural gas distribution utilities have weather or revenue normalization mechanisms that mitigate revenue fluctuations from customer consumption changes. Atlanta Gas Light operates in a deregulated environment in which Marketers rather than a traditional utility sell natural gas to end-use customers and earns revenue by charging rates to its customers based primarily on monthly fixed charges that are set by the Georgia PSC.

In addition to natural gas cost recovery mechanisms, other cost recovery mechanisms and regulatory riders, which vary by utility, allow recovery of certain costs, such as those related to infrastructure replacement programs as well as environmental remediation, energy efficiency plans, and bad debts.

See Note 2 to the financial statements under "Southern Company Gas" in Item 8 herein for a discussion of rate matters and certain cost recovery mechanisms.

Integrated Resource Planning

Each of the traditional electric operating companies continually evaluates its electric generating resources in order to ensure that it maintains a cost-effective and reliable mix of resources to meet the existing and future demand requirements of its customers. In addition, each year the Southern Company system engages in a scenario planning process, developing scenarios which look out over a 30-year horizon. For 2025, scenarios considered a range of views regarding pressure on CO2 emissions, load growth, supply options, and fuel prices. Views regarding future pressure on CO2 emissions include a fee beginning between $0 and $50 per metric ton rising above inflation over the 30-year planning period. See MANAGEMENT'S DISCUSSION AND ANALYSIS – FUTURE EARNINGS POTENTIAL – "Environmental Matters" in Item 7 herein for a discussion of existing and potential environmental regulations that may impact the future generating resource needs of the traditional electric operating companies, as well as a discussion of the Southern Company system's continued generating fleet transition.

Alabama Power

Triennially, Alabama Power provides an IRP report to the Alabama PSC. This report overviews Alabama Power's resource planning process and contains information that serves as the foundation for certain decisions affecting Alabama Power's portfolio of supply-side and demand-side resources. The IRP report facilitates Alabama Power's ability to provide reliable and cost-effective electric service to customers, while accounting for the risks and uncertainties inherent in planning for resources sufficient to meet expected customer demand. Under State of Alabama law, a CCN must be obtained from the Alabama PSC before Alabama Power constructs any new generating facility, unless such construction is an ordinary extension of an existing system in the usual course of business. Alabama Power provided its most recent IRP to the Alabama PSC during 2025. On August 13, 2025, the Alabama PSC approved a CCN authorizing Alabama Power to complete the acquisition of the Lindsay Hill Generating station. The transaction closed on September 30, 2025. See Note 2 to the financial statements under "Alabama Power – Rate CNP New Plant" in Item 8 herein for additional information.

I-12

Table of Contents Index to Financial Statements

Georgia Power

Triennially, Georgia Power must file an IRP with the Georgia PSC that specifies how it intends to meet the future electric service needs of its customers through a combination of demand-side and supply-side resources. The Georgia PSC, under state law, must certify any new demand-side or supply-side resources serving retail customers. Once certified, the lesser of actual or certified construction costs and purchased power costs is recoverable through rates. Georgia Power may request cost recovery for costs greater than those approved by the Georgia PSC if proven to be prudent and reasonable. Certified costs may be excluded from recovery only on the basis of fraud, concealment, failure to disclose a material fact, imprudence, or criminal misconduct. In April 2024, the Georgia PSC approved Georgia Power's 2023 IRP Update as modified by a stipulation among Georgia Power, the staff of the Georgia PSC, and certain intervenors, which limited recovery of certain costs over the certified amount for Plant Yates Units 8, 9, and 10. 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.

On September 4, 2025, the Georgia PSC approved Georgia Power's request to certify a Georgia Power-owned battery energy storage facility with a capacity of 200 MWs and a projected COD in 2027. On December 19, 2025, the Georgia PSC approved Georgia Power's request, as modified by a stipulation between Georgia Power and the staff of the Georgia PSC, to certify resources totaling 9,885 MWs with projected CODs or delivery commencement dates between 2027 and 2030. As included in the 2022 IRP final order, on February 11, 2026, Georgia Power initiated an RFP for up to 500 MWs of capacity for battery energy storage facilities with projected CODs or delivery commencement dates by 2031.

See Note 2 to the financial statements under "Georgia Power – Integrated Resource Plans" and " – Rate Plans" in Item 8 herein for additional information.

Mississippi Power

Triennially, Mississippi Power must file an IRP with the Mississippi PSC, as well as an update at approximately the mid-point of the three-year cycle. The IRP must include long-term plans to best meet the needs of electric utility customers through a combination of demand-side and supply-side resources and considering transmission needs. The IRP filing is not intended to supplant or replace the Mississippi PSC's existing regulatory processes for petition and approval of CPCNs for new generating resources. In April 2024, Mississippi Power filed its 2024 IRP with the Mississippi PSC. The Mississippi PSC did not note any deficiencies within the prescribed 120-day review period; therefore, the filing was concluded. On January 9, 2025, Mississippi Power notified the Mississippi PSC of its intent to extend the retirement date of Plant Daniel Unit 2 and potentially extend the retirement dates of other fossil steam units beyond their current 2028 retirement dates in order to serve recently signed economic development loads of approximately 600 MWs. Mississippi Power has since acquired FP&L's 50% ownership interest in Plant Daniel Units 1 and 2. In 2026, Mississippi Power is expected to file an update to its 2024 IRP with the Mississippi PSC. Mississippi Power must also file an annual report on energy delivery improvements, the latest of which was filed in November 2025. See Note 2 to the financial statements under "Mississippi Power – Integrated Resource Plans" and " – Plant Daniel" in Item 8 herein for additional information.

Human Capital

Southern Company system management is committed to attracting, developing, and retaining a sustainable workforce and aims to foster a culture of belonging where all employees feel valued. The Southern Company system's values – safety first, intentional inclusion, act with integrity, and superior performance – guide behavior. The Southern Company system had approximately 29,800 employees on its payroll at December 31, 2025 comprised of the following:

At December 31, 2025(*)

Alabama Power6,100

Georgia Power7,700

Mississippi Power1,100

Southern Power500

Southern Company Gas5,000

SCS4,800

Southern Nuclear3,700

PowerSecure and other900

Total Southern Company system29,800

(*)Numbers are rounded to 100s.

I-13

Table of Contents Index to Financial Statements

All Southern Company system employees are located within the United States. Part-time employees represent less than 1% of total employees.

Southern Company system management values an inclusive and innovative workforce. Southern Company's subsidiaries have policies, programs, and processes to help ensure that all employees are included and fairly treated across all job levels. The Southern Company system encourages different ideas and points of view, and its Code of Ethics affirms its expectation that employees treat each other with fairness, respect, and dignity. The Southern Company Board of Directors and management believe that diverse perspectives and experiences are important to help inform management of risk, business strategy, and innovation. Southern Company management leads the Southern Company system's intentional inclusion initiatives and employee recruitment, retention, and development efforts. The Board, principally through its Compensation and Talent Development Committee, oversees these efforts.

Southern Company system management supports various employee-led groups to provide formal and informal networks of colleagues that can help promote belonging, improve employee retention, and support development.

Southern Company system management recognizes the importance of attracting and retaining an appropriately qualified workforce. Southern Company system management uses a variety of strategies to attract and retain talent, including working with high schools, technical schools, universities, and military installations to fill many entry-level positions. The recruiting strategy also includes partnerships with professional associations and local communities to recruit mid-career talent. The addition of external hires augments the existing workforce to meet changing business needs, address any critical skill gaps, and supplement and enhance the Southern Company system's talent pipeline.

The Southern Company system supports the well-being of its employees through a comprehensive total rewards strategy with three measurable categories: physical, financial, and emotional well-being. The Southern Company system provides competitive salaries, annual incentive awards for nearly all employees, and health, welfare, and retirement benefits. The Southern Company system has a qualified defined benefit, trusteed pension plan and a qualified defined contribution, trusteed 401(k) plan which provides a competitive company-matching contribution. Substantially all Southern Company system employees are eligible to participate in these plans. There are differences between the pension plan benefit formulas based on when and by which subsidiary an employee is hired. See Note 11 to the financial statements in Item 8 herein for additional information. At December 31, 2025, the average age of the Southern Company system employees was 44 and the average tenure with the Southern Company system was 13 years. Turnover rate, calculated as the percent of employees that terminated employment with the Southern Company system, including voluntary and involuntary terminations and retirements, divided by total employees, was 6.3%.

Southern Company system management is committed to developing talent and helping employees succeed by providing development opportunities along with purposeful people moves as part of individual development plans and succession planning processes. The Southern Company system has multiple development programs, including programs targeted toward all employees, high potential employees, first-level managers, managers of managers, and executives. Additionally, Southern Company system management strives to deliver consistent needs-based training and solutions as workplace needs evolve.

Southern Company system management believes the safety of employees and customers is paramount. The Southern Company system seeks to meet or exceed applicable laws and regulations while continually improving its safety technologies and processes. The Southern Company System Safety and Health Council, which includes leaders from each Registrant, works collectively across the Southern Company system to provide safety leadership, share learning, work collaboratively to address safety-related issues, and govern the consistency of safety programs. The safety programs are focused on the prevention and elimination of life-altering events, serious injuries, and fatalities. These programs include continuous process improvements to put critical controls in place to prevent serious injuries, promote learning, and implement appropriate corrective actions. Southern Company's safety metrics include the serious injury rate and the number of fatalities. The serious injury rate represents the number of incidents per 100 employees and is calculated by taking the number of serious injuries multiplied by 200,000 workhours and dividing by the total employee workhours during the year. A serious injury is one that is life-threatening or life-changing (temporary or permanent) for the employee. Serious injury examples, as defined by applicable safety regulators, include fatalities, amputations, trauma to organs, certain bone fractures, certain soft tissue injuries, severe burns, and eye injuries. In 2025, the Southern Company system had a serious injury rate of 0.03 and no fatal injuries.

The Southern Company system also has longstanding relationships with labor unions. The traditional electric operating companies, Southern Nuclear, and the natural gas distribution utilities have separate agreements with local unions of the IBEW, which generally apply to operating, maintenance, and construction employees. These agreements cover wages, benefits, terms of the pension plans, working conditions, and procedures for handling grievances and arbitration. The Southern Company system also partners with the IBEW to provide training programs to develop technical skills and career opportunities.

At December 31, 2025, approximately 32% of Southern Company system employees were covered by agreements with unions, with agreements expiring between 2026 and 2030.

I-14

Table of Contents Index to Financial Statements