Form 8-K

8-K — SOUTHERN CO

Accession: 0000092122-26-000036

Filed: 2026-04-30

Period: 2026-04-30

CIK: 0000092122

SIC: 4911 (ELECTRIC SERVICES)

Item: Results of Operations and Financial Condition

Documents

8-K — so-20260430.htm (Primary)

EX-99 (ex99-pressreleaseq12026.htm)

GRAPHIC (socologoa22.gif)

XML — IDEA: XBRL DOCUMENT (R1.htm)

8-K

8-K (Primary)

Filename: so-20260430.htm · Sequence: 1

so-20260430

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D. C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported) April 30, 2026

Commission

File Number Registrant,

State of Incorporation,

Address and Telephone Number I.R.S. Employer

Identification No.

1-3526 The Southern Company 58-0690070

(A Delaware Corporation)

30 Ivan Allen Jr. Boulevard, N.W.

Atlanta, Georgia 30308

(404) 506-5000

1-3164 Alabama Power Company 63-0004250

(An Alabama Corporation)

600 North 18th Street

Birmingham, Alabama 35203

(205) 257-1000

1-6468 Georgia Power Company 58-0257110

(A Georgia Corporation)

241 Ralph McGill Boulevard, N.E.

Atlanta, Georgia 30308

(404) 506-6526

001-11229 Mississippi Power Company 64-0205820

(A Mississippi Corporation)

2992 West Beach Boulevard

Gulfport, Mississippi 39501

(228) 864-1211

001-37803 Southern Power Company 58-2598670

(A Delaware Corporation)

30 Ivan Allen Jr. Boulevard, N.W.

Atlanta, Georgia 30308

(404) 506-5000

1-14174 Southern Company Gas 58-2210952

(A Georgia Corporation)

Ten Peachtree Place, N.E.

Atlanta, Georgia 30309

(404) 584-4000

The names and addresses of the registrants have not changed since the last report.

This combined Form 8-K is furnished separately by six registrants: The Southern Company, Alabama Power Company, Georgia Power Company, Mississippi Power Company, Southern Power Company and Southern Company Gas. Information contained herein relating to each registrant is furnished by each registrant solely on its own behalf. Each registrant makes no representation as to information relating to the other registrants.

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrants under any of the following provisions:

☐

Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐

Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐

Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐

Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Registrant Title of each class Trading

Symbol(s) Name of each exchange

on which registered

The Southern Company Common Stock, par value $5 per share SO New York Stock Exchange

The Southern Company Series 2017B 5.25% Junior Subordinated Notes due 2077 SOJC New York Stock Exchange

The Southern Company Series 2020A 4.95% Junior Subordinated Notes due 2080 SOJD New York Stock Exchange

The Southern Company

Series 2020C 4.20% Junior Subordinated Notes due 2060

SOJE New York Stock Exchange

The Southern Company Series 2021B 1.875% Fixed-to-Fixed Reset Rate Junior Subordinated Notes due 2081 SO 81 New York Stock Exchange

The Southern Company Series 2025A 6.50% Junior Subordinated Notes due 2085 SOJF New York Stock Exchange

The Southern Company 2025 Series A Corporate Units SOMN New York Stock Exchange

Georgia Power Company Series 2017A 5.00% Junior Subordinated Notes due 2077 GPJA New York Stock Exchange

Southern Power Company Series 2016B 1.850% Senior Notes due 2026 SO/26A New York Stock Exchange

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). (Response applicable to each registrant)

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 2.02 Results of Operations and Financial Condition

The information in this Current Report on Form 8-K, including the exhibits attached hereto, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities under that Section. Furthermore, such information, including the exhibits attached hereto, shall not be deemed to be incorporated by reference in any filing under the Securities Act of 1933, as amended, except as shall be expressly set forth by specific reference in such filing.

On April 30, 2026, The Southern Company (“Southern Company”) issued a press release regarding its earnings for the three-month period ended March 31, 2026, including certain additional information regarding the financial results for such period. A copy of this release is being furnished as Exhibit 99 to this Current Report on Form 8-K.

Use of Non-GAAP Financial Measures

Exhibit 99 to this Current Report on Form 8-K includes earnings and earnings per share in accordance with generally accepted accounting principles (“GAAP”) for the three-month periods ended March 31, 2026 and 2025. The exhibit also includes earnings and earnings per share (1) for the three-month periods ended March 31, 2026 and 2025, excluding accelerated depreciation related to the repowering of certain wind facilities at Southern Power Company, (2) for the three-month period ended March 31, 2026, excluding (a) costs associated with the extinguishment of debt at Southern Company and (b) an estimated loss at Southern Company Gas related to costs associated with Nicor Gas capital investments disallowed by the Illinois Commerce Commission, and (3) for the three-month period ended March 31, 2025, excluding charges (net of salvage proceeds) and credits, associated legal expenses (net of insurance recoveries), and tax impacts related to plants under construction. The attached exhibit includes additional information regarding these excluded items, as well as reconciliations of each non-GAAP financial measure to the most comparable financial measure under GAAP. Southern Company believes the presentation of earnings and earnings per share, excluding these items, is useful to investors

because it provides investors with additional information to evaluate the performance of Southern Company’s ongoing business activities. Southern Company management also uses earnings and earnings per share, excluding the effect of these items, to evaluate the performance of Southern Company’s ongoing business activities. The presentation of this additional information is not meant to be considered a substitute for financial measures prepared in accordance with GAAP.

Exhibits

Exhibit 99 contains business segment information for Alabama Power Company, Georgia Power Company, Mississippi Power Company, Southern Power Company and Southern Company Gas. Accordingly, this report is also being furnished on behalf of each such registrant.

Exhibit 99

Press Release.

Exhibit 104 Cover Page Interactive Data File – The cover page iXBRL tags are embedded within the inline XBRL document.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, each of the registrants has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Date: April 30, 2026 THE SOUTHERN COMPANY

/s/Matthew M. Kim

Matthew M. Kim

Comptroller

ALABAMA POWER COMPANY

GEORGIA POWER COMPANY

MISSISSIPPI POWER COMPANY

SOUTHERN POWER COMPANY

SOUTHERN COMPANY GAS

By /s/Melissa K. Caen

Melissa K. Caen

Assistant Secretary

EX-99

Filename: ex99-pressreleaseq12026.htm · Sequence: 2

Document

Exhibit 99

Page 1

News

Media Contact: Southern Company Media Relations

404-506-5333 or 1-866-506-5333

southerncompany.com

Investor Relations Contact: Greg MacLeod

404-685-4194

gbmacleo@southernco.com

April 30, 2026

Southern Company reports first-quarter 2026 earnings

ATLANTA – Southern Company today reported first-quarter earnings of $1.4 billion, or $1.21 per share, in 2026 compared with earnings of $1.3 billion, or $1.21 per share, in the first quarter of 2025.

Excluding the items described under “Net Income – Excluding Items” in the table below, Southern Company earned $1.5 billion, or $1.32 per share, during the first quarter of 2026, compared with $1.4 billion, or $1.23 per share, during the first quarter of 2025.

Non-GAAP Financial Measures

Three Months Ended March

Net Income – Excluding Items (in millions) 2026 2025

Net Income – As Reported $ 1,356 $ 1,334

Less:

Accelerated Depreciation from Repowering (154) (26)

Tax Impact 34 6

Loss on Extinguishment of Debt

(11) —

Tax Impact 3 —

Estimated Loss on Nicor Gas Capital Investments (2) —

Tax Impact — —

Estimated Loss on Plants Under Construction — (3)

Tax Impact — 1

Net Income – Excluding Items $ 1,486 $ 1,356

Average Shares Outstanding – (in millions) 1,124 1,100

Basic Earnings Per Share – Excluding Items

$ 1.32 $ 1.23

NOTE: For more information regarding these non-GAAP adjustments, see the footnotes accompanying the Financial Highlights page of the earnings package.

Adjusted earnings drivers for the first quarter of 2026, as compared with 2025, were higher utility revenues, partially offset by milder than normal weather at the regulated electric utilities and higher interest expense.

First-quarter 2026 operating revenues were $8.4 billion, compared with $7.8 billion for the first quarter of 2025, an increase of 8.0%.

“Southern Company is delivering on our plans to serve growth in a way that is both beneficial and protective for existing customers,” said Chris Womack, chairman, president and CEO of Southern Company. “As our region continues to grow, we’re investing in the infrastructure needed to support that growth in a way that provides long-term value while staying grounded in what our customers value most – reliability they can count on and a focus on keeping rates stable. We're uniquely positioned to do this because of our scale, skill and expertise, all of which are focused on putting our customers and communities first.”

Page 2

Southern Company’s first-quarter earnings slides with supplemental financial information are available at investor.southerncompany.com.

Southern Company’s financial analyst call will begin at 1 p.m. Eastern Time today, during which Womack and Chief Financial Officer David P. Poroch will discuss earnings and provide a general business update. Investors, media and the public may listen to a live webcast of the call and view associated slides at investor.southerncompany.com. A replay of the webcast will be available on the site for 12 months.

About Southern Company

Southern Company (NYSE: SO) is a leading energy provider serving 9 million customers across the Southeast and beyond through its family of companies. The company has electric operating companies in three states, natural gas distribution companies in four states, a competitive generation company, a leading distributed energy solutions provider with national capabilities, a fiber optics network and telecommunications services. Our uncompromising values ensure we put the needs of those we serve at the center of everything we do and are the key to our sustained success, driven by our nearly 30,000 employees dedicated to delivering exceptional service. To learn more, visit www.southerncompany.com.

Cautionary Note Regarding Forward-Looking Statements

Certain information contained in this release is forward-looking information based on current expectations and plans that involve risks and uncertainties. Forward-looking information includes, among other things, statements concerning plans to serve projected future growth and the potential benefits thereof. Southern Company cautions that there are certain factors that can cause actual results to differ materially from the forward-looking information that has been provided. The reader is cautioned not to put undue reliance on this forward-looking information, which is not a guarantee of future performance and is subject to a number of uncertainties and other factors, many of which are outside the control of Southern Company; accordingly, there can be no assurance that such suggested results will be realized. The following factors, in addition to those discussed in Southern Company’s Annual Report on Form 10-K for the year ended December 31, 2025, Quarterly Report on Form 10-Q for the quarter ended March 31, 2026 and subsequent securities filings, could cause actual results to differ materially from management expectations as suggested by such forward-looking information: the impact of recent and future federal and state legal and regulatory changes, including tax, environmental and other laws and regulations to which Southern Company and its subsidiaries are subject, as well as changes in application of existing laws, regulations and guidance; the extent and timing of costs and legal requirements related to coal combustion residuals; current and future litigation or regulatory investigations, proceedings, or inquiries; the effects, extent, and timing of the entry of additional competition in the markets in which Southern Company’s subsidiaries operate, including from the development and deployment of alternative energy sources; variations in demand for electricity and natural gas, including uncertainties related to projected significant growth in electricity demand driven primarily by data centers and other large load customers, and the related requirement for substantial new generation and transmission investments, creating capital access and revenue recovery risks for the traditional electric operating companies; customer affordability matters; available sources and costs of natural gas and other fuels and commodities; the ability to complete necessary or desirable pipeline expansion or infrastructure projects, limits on pipeline capacity, public and policymaker support for such projects, and operational interruptions to natural gas distribution and transmission activities; transmission constraints; the ability to control costs and avoid cost and schedule overruns during the development, construction, and operation of facilities or other projects due to challenges which include, but are not limited to, changes in labor costs, availability, and productivity, challenges with the management of contractors or vendors, subcontractor performance, adverse weather conditions, shortages, delays, increased costs, or inconsistent quality of equipment, materials, and labor, contractor or supplier delay, the impacts of inflation and trade policies (including tariffs and other trade measures) of the United States and other countries, delays due to judicial or regulatory action, nonperformance under construction, operating, or other agreements, operational readiness, including specialized operator training and required site safety programs,

Page 3

engineering or design problems or any remediation related thereto, design and other licensing-based compliance matters, challenges with start-up activities, including major equipment failure or system integration, and/or operational performance, challenges related to future epidemic or pandemic health events, continued public and policymaker support for projects, environmental and geological conditions, delays or increased costs to interconnect facilities to transmission grids, and increased financing costs as a result of changes in interest rates or as a result of project delays; legal proceedings and regulatory approvals and actions related to past, ongoing, and proposed construction projects, including state public service commission or other applicable state regulatory agency approvals and Federal Energy Regulatory Commission and U.S. Nuclear Regulatory Commission actions; the ability to construct facilities in accordance with the requirements of permits and licenses, to satisfy any environmental performance standards and the requirements of tax credits and other incentives, and to integrate facilities into the Southern Company system upon completion of construction; investment performance of the employee and retiree benefit plans and nuclear decommissioning trust funds and, with respect to retiree benefit plans, changes in actuarial assumptions and differences between the assumptions and actual values, any of the foregoing of which could cause additional funding requirements; advances in technology, including the pace and extent of development of low- to no-carbon energy and battery energy storage technologies and the impact of advancing technology on data center and other large load customer demand; performance of counterparties under ongoing renewable energy partnerships and development agreements; state and federal rate regulations and the impact of pending and future rate cases and negotiations, including rate actions relating to return on equity, equity ratios, additional generating capacity and transmission facilities, extension of retirement dates for fossil fuel plants, and fuel and other cost recovery mechanisms; the ability to successfully operate Southern Company’s electric utilities’ generation, transmission, distribution, and battery energy storage facilities, as applicable, and Southern Company Gas’ natural gas distribution and storage facilities and the successful performance of necessary corporate functions; the inherent risks involved in operating nuclear generating facilities; the inherent risks involved in generation, transmission, and distribution of electricity and transportation and storage of natural gas, including accidents, explosions, fires, mechanical problems, discharges or releases of toxic or hazardous substances or gases, and other environmental risks; the performance of projects undertaken by the non-utility businesses and the success of efforts to invest in and develop new opportunities; internal restructuring or other restructuring options that may be pursued; potential business strategies, including acquisitions or dispositions of assets or businesses, or interests therein, which cannot be assured to be completed or beneficial to Southern Company or its subsidiaries; the ability of counterparties of Southern Company and its subsidiaries to make payments as and when due and to perform as required; the ability to obtain new short- and long-term contracts with wholesale customers; the direct or indirect effect on the Southern Company system’s business resulting from cyber intrusion or physical attack and the threat of cyber and physical attacks; global and U.S. economic conditions, including impacts from geopolitical conflicts, recession, inflation, changes in trade policies (including tariffs and other trade measures) of the United States and other countries, interest rate fluctuations, and financial market conditions, and the results of financing efforts; prolonged or recurring U.S. federal government shutdowns; access to capital markets and other financing sources; changes in Southern Company’s and any of its subsidiaries’ credit ratings; the ability of Southern Company’s electric utilities to obtain additional generating capacity (or sell excess generating capacity) at competitive prices; catastrophic events such as fires, including wildfires, land movement, earthquakes, explosions, floods, high winds, tornadoes, hurricanes and other storms, solar flares, droughts, future epidemic or pandemic health events, wars, political unrest, or other similar occurrences; the direct or indirect effects on the Southern Company system’s business resulting from incidents affecting the U.S. electric grid, natural gas pipeline infrastructure, or operation of generating or storage resources; impairments of goodwill or long-lived assets; and the effect of accounting pronouncements issued periodically by standard-setting bodies. Southern Company expressly disclaims any obligation to update any forward-looking information.

###

Page 4

Southern Company

Financial Highlights

(In Millions Except Earnings Per Share)

Three Months Ended March

Net Income – As Reported

2026 2025

Traditional Electric Operating Companies $ 1,113 $ 1,026

Southern Power 4 87

Southern Company Gas 447 418

Total 1,564 1,531

Parent Company and Other (208) (197)

Net Income – As Reported $ 1,356 $ 1,334

Basic Earnings Per Share(1)

$ 1.21 $ 1.21

Average Shares Outstanding 1,124 1,100

Non-GAAP Financial Measures

Three Months Ended March

Net Income – Excluding Items

2026 2025

Net Income – As Reported $ 1,356 $ 1,334

Less:

Accelerated Depreciation from Repowering(2)

(154) (26)

Tax Impact 34 6

Loss on Extinguishment of Debt(3)

(11) —

Tax Impact 3 —

Estimated Loss on Nicor Gas Capital Investments(4)

(2) —

Tax Impact — —

Estimated Loss on Plants Under Construction(5)

— (3)

Tax Impact — 1

Net Income – Excluding Items $ 1,486 $ 1,356

Basic Earnings Per Share – Excluding Items $ 1.32 $ 1.23

See Notes on the following page.

Page 5

Southern Company

Financial Highlights

Notes

(1)Dilution is not material in any period presented. Diluted earnings per share was $1.20 and $1.21 for the three months ended March 31, 2026 and 2025, respectively.

(2)Earnings include pre-tax charges of $154 million ($120 million after tax) and $26 million ($20 million after tax, net of noncontrolling interest impacts) for the three months ended March 31, 2026 and 2025, respectively, associated with accelerated depreciation related to the repowering of certain wind facilities at Southern Power Company. Accelerated depreciation related to the equipment being replaced will continue until the completion dates of the repowering projects, which are projected to occur through the third quarter 2027. At March 31, 2026, the remaining pre-tax accelerated depreciation is projected to total approximately $335 million in 2026 and $100 million in 2027.

(3)Earnings for the three months ended March 31, 2026 include costs associated with the extinguishment of debt at Southern Company as a result of Southern Company's redemption of certain junior subordinated notes. Similar transaction costs may occur in the future at Southern Company or one of its unregulated subsidiaries; however, the amount and timing of any such costs are uncertain.

(4)Earnings for the three months ended March 31, 2026 include an estimated loss of $2 million (before and after tax) at Southern Company Gas related to costs associated with Nicor Gas capital investments disallowed by the Illinois Commerce Commission in November 2025. Further charges may occur; however, the amount and timing of any such charges are uncertain.

(5)Earnings for the three months ended March 31, 2025 include charges (net of salvage proceeds), associated legal expenses (net of insurance recoveries), and tax impacts related to Mississippi Power Company's integrated coal gasification combined cycle facility project in Kemper County, Mississippi. Dismantlement of the abandoned gasifier-related assets was completed at the end of 2025. Site restoration activities are substantially complete, and any additional costs are expected to be immaterial.

Page 6

Southern Company

Significant Factors Impacting EPS

Three Months Ended March

2026 2025 Change

Earnings Per Share –

As Reported(1)

$ 1.21 $ 1.21 $ —

Significant Factors:

Traditional Electric Operating Companies $ 0.08

Southern Power (0.08)

Southern Company Gas 0.03

Parent Company and Other —

Increase in Shares (0.03)

Total – As Reported

$ —

Three Months Ended March

Non-GAAP Financial Measures 2026 2025 Change

Earnings Per Share –

Excluding Items

$ 1.32 $ 1.23 $ 0.09

Total – As Reported

$ —

Less:

Accelerated Depreciation from Repowering(2)

(0.08)

Loss on Extinguishment of Debt(3)

(0.01)

Estimated Loss on Nicor Gas Capital Investments(4)

—

Estimated Loss on Plants Under Construction(5)

—

Total – Excluding Items

$ 0.09

See Notes on the following page.

Page 7

Southern Company

Significant Factors Impacting EPS

Notes

(1)Dilution is not material in any period presented. Diluted earnings per share was $1.20 and $1.21 for the three months ended March 31, 2026 and 2025, respectively.

Page 8

Southern Company

EPS Earnings Analysis

Description

Three Months Ended

March

2026 vs. 2025

Retail Sales 6¢

Retail Revenue Impacts (1)

Weather (5)

Wholesale and Other Operating Revenues

Non-Fuel Operations and Maintenance Expenses(1)

Depreciation and Amortization —

Allowance for Equity Funds Used During Construction

Interest Expense and Other (3)

Income Taxes 1

Total Traditional Electric Operating Companies 8¢

Southern Power 1

Southern Company Gas 3

Parent Company and Other —

Increase in Shares (3)

Total Change in EPS (Excluding Items) 9¢

Accelerated Depreciation from Repowering(2)

(8)

Loss on Extinguishment of Debt(3)

(1)

Estimated Loss on Nicor Gas Capital Investments(4)

—

Estimated Loss on Plants Under Construction(5)

—

Total Change in EPS (As Reported) —¢

See Notes on the following page.

Page 9

Southern Company

EPS Earnings Analysis

Notes

(1)Excludes gains/losses on asset sales, which are included in "Interest Expense and Other." Includes non-service cost-related benefits income.

Page 10

Southern Company

Consolidated Earnings

As Reported

Three Months Ended March

2026 2025 Change

(in millions)

Retail electric revenues:

Fuel $ 1,256 $ 1,217 $ 39

Non-fuel 3,384 3,384 —

Wholesale electric revenues 965 744 221

Other electric revenues 265 242 23

Natural gas revenues 2,191 1,839 352

Other revenues 336 349 (13)

Total operating revenues 8,397 7,775 622

Fuel and purchased power 1,735 1,542 193

Cost of natural gas 926 674 252

Cost of other sales 181 199 (18)

Non-fuel operations and maintenance

1,653 1,619 34

Depreciation and amortization 1,420 1,286 134

Taxes other than income taxes 464 445 19

Total operating expenses 6,379 5,765 614

Operating income 2,018 2,010 8

Allowance for equity funds used during construction 121 73 48

Earnings from equity method investments 50 32 18

Interest expense, net of amounts capitalized 778 714 64

Other income (expense), net 155 149 6

Income taxes 228 280 (52)

Net income 1,338 1,270 68

Net loss attributable to noncontrolling interests (18) (64) 46

Net income attributable to Southern Company $ 1,356 $ 1,334 $ 22

Certain prior year data may have been reclassified to conform with current year presentation.

Page 11

Southern Company

Kilowatt-Hour Sales and Customers

Three Months Ended March

2026 2025 % Change Weather Adjusted % Change

(in millions)

Kilowatt-Hour Sales

Total Sales 50,192 48,485 3.5 %

Total Retail Sales 36,600 36,442 0.4 % 2.3 %

Residential 12,121 12,633 (4.1) % 0.9 %

Commercial 12,344 11,852 4.2 % 4.6 %

Industrial 12,004 11,824 1.5 % 1.5 %

Other 131 133 (1.9) % (1.9) %

Total Wholesale Sales 13,592 12,043 12.9 % N/A

Period Ended March

2026 2025 % Change

(in thousands)

Regulated Utility Customers

Total Regulated Utility Customers 9,037 8,967 0.8%

Traditional Electric Operating Companies 4,600 4,551 1.1%

Southern Company Gas 4,437 4,416 0.5%

Page 12

Southern Company

Financial Overview

As Reported

Three Months Ended March

2026 2025 % Change

(in millions)

Southern Company –

Operating Revenues $ 8,397 $ 7,775 8.0 %

Earnings Before Income Taxes 1,566 1,550 1.0 %

Net Income Available to Common 1,356 1,334 1.6 %

Alabama Power –

Operating Revenues $ 2,092 $ 2,012 4.0 %

Earnings Before Income Taxes 554 486 14.0 %

Net Income Available to Common 425 375 13.3 %

Georgia Power –

Operating Revenues $ 3,142 $ 3,037 3.5 %

Earnings Before Income Taxes 713 694 2.7 %

Net Income Available to Common 628 596 5.4 %

Mississippi Power –

Operating Revenues $ 472 $ 420 12.4 %

Earnings Before Income Taxes 78 71 9.9 %

Net Income Available to Common 60 55 9.1 %

Southern Power –

Operating Revenues $ 681 $ 567 20.1 %

Earnings (Loss) Before Income Taxes (84) 22 N/M

Net Income Available to Common 4 87 (95.4) %

Southern Company Gas –

Operating Revenues $ 2,191 $ 1,839 19.1 %

Earnings Before Income Taxes 592 548 8.0 %

Net Income Available to Common 447 418 6.9 %

See Financial Highlights pages for discussion of certain significant items occurring during the periods.

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Cover Page Document

Apr. 30, 2026

Document Information [Line Items]

Document Type

8-K

Document Period End Date

Apr. 30, 2026

Entity File Number

1-3526

Entity Registrant Name

The Southern Company

Entity Tax Identification Number

58-0690070

Entity Incorporation, State or Country Code

Entity Address, Address Line One

30 Ivan Allen Jr. Boulevard, N.W

Entity Address, City or Town

Atlanta

Entity Address, State or Province

Entity Address, Postal Zip Code

30308

City Area Code

404

Local Phone Number

506-5000

Written Communications

false

Soliciting Material

false

Pre-commencement Tender Offer

false

Pre-commencement Issuer Tender Offer

false

Entity Emerging Growth Company

false

Entity Central Index Key

0000092122

Amendment Flag

false

Common Stock, par value $5 per share

Document Information [Line Items]

Title of 12(b) Security

Common Stock, par value $5 per share

Trading Symbol

Security Exchange Name

NYSE

Series 2017B 5.25% Junior Subordinated Notes due 2077

Document Information [Line Items]

Title of 12(b) Security

Series 2017B 5.25% Junior Subordinated Notes due 2077

Trading Symbol

SOJC

Security Exchange Name

NYSE

Series 2020A 4.95% Junior Subordinated Notes Due 2080 [Member]

Document Information [Line Items]

Title of 12(b) Security

Series 2020A 4.95% Junior Subordinated Notes due 2080

Trading Symbol

SOJD

Security Exchange Name

NYSE

Series 2020C 4.20% Junior Subordinated Notes due 2060

Document Information [Line Items]

Title of 12(b) Security

Series 2020C 4.20% Junior Subordinated Notes due 2060

Trading Symbol

SOJE

Security Exchange Name

NYSE

Series 2021B 1.875% Fixed-to-Fixed Reset Rate Junior Subordinated Notes due 2081

Document Information [Line Items]

Title of 12(b) Security

Series 2021B 1.875% Fixed-to-Fixed Reset Rate Junior Subordinated Notes due 2081

Trading Symbol

SO 81

Security Exchange Name

NYSE

Series 2025A 6.50% Junior Subordinated Notes due 2085

Document Information [Line Items]

Title of 12(b) Security

Series 2025A 6.50% Junior Subordinated Notes due 2085

Trading Symbol

SOJF

Security Exchange Name

NYSE

2025 Series A Corporate Units

Document Information [Line Items]

Title of 12(b) Security

2025 Series A Corporate Units

Trading Symbol

SOMN

Security Exchange Name

NYSE

Alabama Power Company

Document Information [Line Items]

Entity File Number

1-3164

Entity Registrant Name

Alabama Power Company

Entity Tax Identification Number

63-0004250

Entity Incorporation, State or Country Code

Entity Address, Address Line One

600 North 18th Street

Entity Address, City or Town

Birmingham

Entity Address, State or Province

Entity Address, Postal Zip Code

35203

City Area Code

205

Local Phone Number

257-1000

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Georgia Power Company

Document Information [Line Items]

Entity File Number

1-6468

Entity Registrant Name

Georgia Power Company

Entity Tax Identification Number

58-0257110

Entity Incorporation, State or Country Code

Entity Address, Address Line One

241 Ralph McGill Boulevard, N.E.

Entity Address, City or Town

Atlanta

Entity Address, State or Province

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30308

City Area Code

404

Local Phone Number

506-6526

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Entity Central Index Key

0000041091

Georgia Power Company | Series 2017A 5.00% Junior Subordinated Notes due 2077

Document Information [Line Items]

Title of 12(b) Security

Series 2017A 5.00% Junior Subordinated Notes due 2077

Trading Symbol

GPJA

Security Exchange Name

NYSE

Mississippi Power Company

Document Information [Line Items]

Entity File Number

001-11229

Entity Registrant Name

Mississippi Power Company

Entity Tax Identification Number

64-0205820

Entity Incorporation, State or Country Code

Entity Address, Address Line One

2992 West Beach Boulevard

Entity Address, City or Town

Gulfport

Entity Address, State or Province

Entity Address, Postal Zip Code

39501

City Area Code

228

Local Phone Number

864-1211

Entity Emerging Growth Company

false

Entity Central Index Key

0000066904

Southern Power Company

Document Information [Line Items]

Entity File Number

001-37803

Entity Registrant Name

Southern Power Company

Entity Tax Identification Number

58-2598670

Entity Incorporation, State or Country Code

Entity Address, Address Line One

30 Ivan Allen Jr. Boulevard, N.W.

Entity Address, City or Town

Atlanta

Entity Address, State or Province

Entity Address, Postal Zip Code

30308

City Area Code

404

Local Phone Number

506-5000

Entity Emerging Growth Company

false

Entity Central Index Key

0001160661

Southern Power Company | Series 2016B 1.850% Senior Notes Due 2026 [Member]

Document Information [Line Items]

Title of 12(b) Security

Series 2016B 1.850% Senior Notes due 2026

Trading Symbol

SO/26A

Security Exchange Name

NYSE

Southern Company Gas

Document Information [Line Items]

Entity File Number

1-14174

Entity Registrant Name

Southern Company Gas

Entity Tax Identification Number

58-2210952

Entity Incorporation, State or Country Code

Entity Address, Address Line One

Ten Peachtree Place, N.E.

Entity Address, City or Town

Atlanta

Entity Address, State or Province

Entity Address, Postal Zip Code

30309

City Area Code

404

Local Phone Number

584-4000

Entity Emerging Growth Company

false

Entity Central Index Key

0001004155

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