The Southern Company Series 2020A 4.95% Junior Subordinated Notes due January 30, 2080 Form 4 Filings

Southern Company director Shantella E. Cooper acquired 539 deferred stock units on October 1, 2026, as quarterly director equity retainer paid under the Southern Company 2021 Equity and Incentive Compensation Plan and deferred under the Deferred Compensation Plan for Outside Directors. Each unit represents the right to receive one common share. Her reported position after the transaction was 33,424 deferred stock units, including additional units acquired through dividend reinvestment; the reported per-share price was $83.4700.

Southern Company director James O. Etheredge acquired 539.1159 deferred stock units on October 1, 2026, as a quarterly director equity retainer under the Southern Company 2021 Equity and Incentive Compensation Plan, deferred under the Deferred Compensation Plan for Outside Directors. Each unit represents the right to receive one share of Southern Company common stock. His reported post-transaction balance was 3,446.5131 deferred stock units, including additional units acquired through dividend reinvestment.

Southern Company director John D. Johns acquired 539.1159 deferred stock units on October 1, 2026, as a quarterly director equity retainer under the Southern Company 2021 Equity and Incentive Compensation Plan, deferred under the Deferred Compensation Plan for Outside Directors of The Southern Company. The reported price was $83.4700 per unit. Each unit represents the right to receive one common share. His reported direct position after the transaction was 89,846.2272 units, including additional units acquired through dividend reinvestment. The units are settled in shares following the end of Board service, on dates Johns specifies under the plan.

Southern Company (SO) director David J. Grain acquired 973.4036 deferred stock units on October 1, 2026. The units represent a quarterly director cash and equity retainer paid under the Southern Company 2021 Equity and Incentive Compensation Plan and deferred pursuant to the Deferred Compensation Plan for Outside Directors of The Southern Company. They include additional units acquired through that plan’s dividend reinvestment feature. Grain’s resulting holdings were 88,596.7903 deferred stock units.

Southern Company director William G. Smith Jr. acquired 988.3791 deferred stock units on October 1, 2026, as part of the quarterly director cash and equity retainer deferred under the outside-director Deferred Compensation Plan. The transaction lists a price of $83.4700 per share. His reported balance afterward was 165,393.0850 deferred stock units, including additional units acquired through dividend reinvestment.

Southern Company director Kristine L. Svinicki acquired 539.1159 deferred stock units on October 1, 2026, as a quarterly director equity retainer under the Southern Company 2021 Equity and Incentive Compensation Plan, deferred under the Deferred Compensation Plan for Outside Directors. Each unit represents the right to receive one share of Southern Company common stock. Her reported resulting position was 12,235.2278 deferred stock units, including additional units acquired through dividend reinvestment.

Southern Company director David E. Meador acquired 913.5019 deferred stock units on October 1, 2026, as a quarterly director cash and equity retainer under the Southern Company 2021 Equity and Incentive Compensation Plan, deferred under the Deferred Compensation Plan for Outside Directors. Each unit represents the right to receive one common share; settlement occurs in shares after Board service ends on dates selected by the reporting person. Meador's reported post-transaction balance was 11,158.8237 deferred stock units, including additional units from dividend reinvestment.

Southern Company director John M. Turner Jr. acquired 913.5019 deferred stock units on October 1, 2026, representing a quarterly director cash and equity retainer deferred under the Southern Company 2021 Equity and Incentive Compensation Plan and the Deferred Compensation Plan for Outside Directors. Each unit represents the right to receive one share of common stock. His resulting reported holding was 4,359.3386 deferred stock units, including additional units from dividend reinvestment. Settlement is in shares on dates following termination of Board service, as specified by the director.

Southern Company director Lizanne Thomas acquired 539.1159 deferred stock units on October 1, 2026, representing her quarterly director equity retainer, paid under the Southern Company 2021 Equity and Incentive Compensation Plan and deferred under the Deferred Compensation Plan for Outside Directors. Each unit represents the right to receive one share of Southern Company common stock. Her resulting balance was 8,363.0551 deferred stock units, including units acquired through dividend reinvestment.

Southern Company director Anthony F. Earley Jr. reported compensation-related acquisitions on October 1, 2026: 539.1159 Deferred Stock Units representing his quarterly director equity retainer and 262.0702 Phantom Stock Units representing his quarterly director cash retainer, both deferred under the Deferred Compensation Plan. Each Deferred Stock Unit represents a right to one common share; each Phantom Stock Unit represents a right to the cash value of one share. His reported balances after the transactions were 32,408.3358 and 1,136.2169 units, respectively, including additional units credited for dividends. No Rule 10b5-1 plan is reported.

Southern Company Comptroller Matthew M. Kim reported a sale of 100 shares of Southern Company common stock on October 1, 2026, at $82.73 per share, under a Rule 10b5-1 trading plan. He held 4,888 shares directly after the sale and reported 1,222 shares indirectly through a 401(k).

SOUTHERN CO (SO) reported that Comptroller Matthew M. Kim sold 1,400 shares of Southern Company common stock on September 3, 2026 in a sale classified as an open-market or private transaction at $88.87 per share. After this sale, he held 4,988 shares directly and 1,222.207 shares indirectly through a 401(k). No Rule 10b5-1 trading plan is reported for these transactions.

SOUTHERN CO (SO) reported that Peter P. Sena III, Chairman, President & CEO of Southern Nuclear Company (SNC), sold 4,266 shares of Southern Company Common Stock on September 3, 2026 in an open-market or private transaction at $88.59 per share.

After this sale, he directly holds 26,935 shares of Southern Company Common Stock, and the transaction is affirmed as made under a Rule 10b5-1 trading plan.

SOUTHERN CO (SO) reports that Comptroller Matthew M. Kim sold 100 shares of Southern Company Common Stock on September 1, 2026, at $88.45 per share in an open-market or private transaction under a Rule 10b5-1 trading plan. After this sale, he holds 6,399.55 shares directly and 1,222.207 shares indirectly through a 401(k).

SOUTHERN CO executive Sterling A. Spainhour Jr., EVP & CLO, reported selling 3,333 shares of Southern Company Common Stock on 2026-08-06 at $94.02 per share in an open-market or private transaction. The transaction was made under a Rule 10b5-1 trading plan, leaving 35,219 shares held directly plus 951.3316 shares held indirectly through a 401(k).

Southern Company reported that Comptroller Matthew M. Kim sold 100 shares of Southern Company Common Stock on 2026-08-03 at $94.28 per share in an open market or private transaction pursuant to a Rule 10b5-1 trading plan.

After the sale he held 6,488 shares directly and 1,222.207 shares indirectly through a 401(k) plan.

Southern Company’s comptroller, Matthew M. Kim, reported a small open-market sale of common stock. On 2026-07-01, he sold 100 shares of Southern Company Common Stock at $95.77 per share.

After this sale, Kim directly holds 6,588 shares and indirectly holds 1,212.1903 shares through a 401(k) plan. The filing shows no option exercises or derivative positions, indicating this was a straightforward, modest open-market sale alongside ongoing retirement-plan holdings.

Southern Company director Anthony F. Earley Jr. reported routine compensation-related awards rather than open-market trades. On July 1, 2026, he acquired 473.0866 deferred stock units tied to Southern Company common stock, bringing his deferred stock unit balance to 31,592.0786 units. He also received 229.9727 phantom stock units, increasing his phantom unit holdings to 858.9727 units.

Footnotes explain these are quarterly board retainers deferred under company plans. Deferred stock units will be settled in shares of common stock after his board service ends, while phantom stock units will be settled in cash based on the value of one Southern Company share. Both types of units also receive additional credits for reinvested dividends.

Southern Co director Shantella E. Cooper received a grant of 473.0866 deferred stock units as part of her quarterly director equity retainer. These units were awarded under the Southern Company 2021 Equity and Incentive Compensation Plan and deferred into the Deferred Compensation Plan for Outside Directors.

Each deferred stock unit represents the right to receive one share of Southern Company common stock, generally after her Board service ends. Following this award, she holds a total of 32,605.9488 deferred stock units directly, with no exercise or expiration date on these units.

Southern Company director William G. Smith Jr. received a grant of deferred stock units as part of his regular director compensation. He acquired 867.3255 deferred stock units valued at $95.12 per unit under the Southern Company 2021 Equity and Incentive Compensation Plan and deferred them into the Deferred Compensation Plan for Outside Directors. Each unit represents the right to receive one share of Southern Company common stock, generally delivered after his Board service ends. Following this award and dividend reinvestment activity, his deferred stock unit balance stands at 163,012.5325 units.

MEADOR DAVID E reported acquisition or exercise transactions in this Form 4 filing.

Southern Company director David E. Meador received a grant of 801.619 deferred stock units as part of his quarterly director cash and equity retainers. These units were awarded under the Southern Company 2021 Equity and Incentive Compensation Plan and deferred into the Deferred Compensation Plan for Outside Directors.

Each deferred stock unit represents the right to receive one share of Southern Company common stock, to be settled after Meador’s service on the Board ends as specified in his deferral elections. Following this award and dividend reinvestment activity, he holds a total of 9,452.0657 deferred stock units.

Southern Company director David J. Grain received a routine compensation award of deferred stock units. On this date, he acquired 854.1842 deferred stock units tied to Southern Company common stock, reflecting quarterly director cash and equity retainers under the 2021 Equity and Incentive Compensation Plan.

After this award, Grain directly holds a total of 86,881.3948 deferred stock units. These units are settled in shares of Southern Company common stock after his service on the Board ends, according to his elections under the Deferred Compensation Plan, and the total includes units credited through dividend reinvestment.

Southern Co director John M. Turner Jr. received 801.619 deferred stock units as part of his quarterly cash and equity retainers under the company’s 2021 Equity and Incentive Compensation Plan. Each deferred stock unit represents the right to receive one share of Southern Company common stock.

The retainers were deferred into the Deferred Compensation Plan for Outside Directors, which also credits additional units through a dividend reinvestment feature. After this grant, Turner holds a total of 3,416.6575 deferred stock units, which will be settled in shares of common stock after his board service ends, with no exercise or expiration date.

Southern Company director Lizanne Thomas received a grant of deferred stock units as part of her quarterly director equity retainer. She was awarded 473.0866 deferred stock units, each representing the right to receive one share of Southern Company common stock, based on a reference price of $95.12 per unit. Following this award, her reported balance increased to 7,757.6864 deferred stock units, including units accumulated through the plan’s dividend reinvestment feature. These units are deferred compensation under the company’s equity and incentive compensation plans and will be settled in common shares after her service on the Board ends, with no set exercise or expiration date.

Southern Co director Kristine L. Svinicki received an award of 473.0866 deferred stock units on July 1, 2026 as her quarterly director equity retainer under the Southern Company 2021 Equity and Incentive Compensation Plan.

The grant is deferred under the Deferred Compensation Plan for Outside Directors. Each deferred stock unit represents the right to receive one share of Southern Company common stock, generally settled after her Board service ends. Including units acquired through dividend reinvestment, she now holds a total of 11,597.0696 deferred stock units.

Southern Company director John D. Johns received an award of 473.0866 deferred stock units as part of his quarterly director equity retainer. The units were granted at a reference value of $95.12 per unit and increase his direct holdings of deferred stock units to 88,550.8618 units.

These deferred stock units are granted under the Southern Company 2021 Equity and Incentive Compensation Plan and are deferred pursuant to the Deferred Compensation Plan for Outside Directors. Each unit represents the right to receive one share of Southern Company common stock, generally settled after his service on the board ends, with no exercise or expiration date.

Akella Janaki reported acquisition or exercise transactions in this Form 4 filing.

Southern Company director Janaki Akella received a grant of 473.0866 deferred stock units as a quarterly director equity retainer, valued at $95.12 per unit. These units, which each represent one share of common stock, are deferred until after board service ends, bringing total deferred holdings to 21,178.9803 units.

Etheredge James O reported acquisition or exercise transactions in this Form 4 filing.

Southern Co director James O. Etheredge reported a routine equity compensation grant. He received 473.0866 deferred stock units as part of his quarterly director equity retainer under The Southern Company 2021 Equity and Incentive Compensation Plan. Each unit represents the right to receive one share of Southern Company common stock, to be settled after his Board service ends. Following this grant and related dividend reinvestment, his deferred stock unit balance stands at 2,882.7775 units held directly.

Southern Co executive Peter P. Sena III reported routine equity compensation activity. On June 28, 2026, he acquired 667 performance restricted stock units, representing the second one‑third of an award originally granted on June 28, 2024, including 45 dividend equivalent units. A portion of the resulting common shares, 316 shares, was withheld to satisfy required state and federal tax withholding obligations, rather than sold in the open market. These transactions reflect vesting and tax payments, not discretionary open‑market buying or selling.

Southern Company Comptroller Matthew M. Kim reported a small insider sale of common stock. On June 1, 2026, he completed an open-market sale of 100 shares of Southern Company Common Stock at $91.16 per share.

After this sale, Kim directly holds 6,688 shares of Southern Company Common Stock and indirectly holds 1,212.1903 shares through a 401(k) plan. The transaction size is modest relative to his reported holdings and appears as routine portfolio activity.

Southern Company Chairman, President & CEO Christopher C. Womack reported compensation-related share activity. He exercised performance restricted stock units into 6,898 shares of Southern Company common stock, with 3,414 shares withheld to cover required state and federal tax obligations. Following these transactions, he holds 213,449.2496 shares directly and 2,603.3794 shares indirectly through a 401(k) plan.

Southern Company comptroller Matthew M. Kim reported an open-market sale of Southern Company Common Stock. He sold 100 shares at $96.57 per share. After this sale, he directly owns 6,788 shares of Southern Company Common Stock and also holds 1,212.1903 shares indirectly through a 401(k) plan.

Southern Company comptroller Matthew M. Kim reported routine equity compensation activity involving restricted stock units that converted into common shares. On April 1, 2026, he exercised several Southern Company and performance restricted stock unit awards into common stock, reflecting scheduled vesting under prior grants.

In connection with these awards, 82 shares of Southern Company common stock were delivered back to the company at $96.94 per share to cover FICA withholding obligations because he is retirement-eligible under the stock grant documents. After these transactions, Kim directly held 6,888 shares of Southern Company common stock.

Southern Company director John D. Johns received a quarterly equity retainer in deferred stock units rather than cash. On this Form 4, he was granted 464.2047 deferred stock units, each tied to one share of Southern Company common stock, at a reference value of $96.94 per unit.

These units are issued under the Southern Company 2021 Equity and Incentive Compensation Plan and are deferred under the Deferred Compensation Plan for Outside Directors. They will be settled in shares of common stock after Johns leaves the Board, with no exercise or expiration date. Following this grant and related dividend reinvestments, his deferred stock unit balance is 87,350.4924 units.

GRAIN DAVID J reported acquisition or exercise transactions in this Form 4 filing.

Southern Company director David J. Grain received a grant of 838.1473 deferred stock units tied to Southern Company common stock as director compensation. The units, valued at $96.94 per unit for reporting purposes, were credited under the company’s 2021 Equity and Incentive Compensation Plan and deferred into the Deferred Compensation Plan for Outside Directors.

Following this grant and related dividend reinvestment credits, Grain holds a total of 85,316.8599 deferred stock units. Each unit represents the right to receive one share of Southern Company common stock, to be settled in shares after his Board service ends. The award is a non‑cash, routine compensation grant rather than an open‑market stock purchase or sale.

Southern Company director John M. Turner Jr. reported receiving a grant of deferred stock units as part of his quarterly director cash and equity retainers under the Southern Company 2021 Equity and Incentive Compensation Plan.

The award covers 786.569 deferred stock units, each tied to one share of Southern Company common stock at a reference price of $96.94. After this grant, Turner holds a total of 2,593.4454 deferred stock units.

The units are credited under the Deferred Compensation Plan for Outside Directors and are settled in shares of common stock after Turner’s board service ends, with no exercise or expiration date. The reported total also includes additional units acquired through the plan’s dividend reinvestment feature.

Southern Company director William G. Smith Jr. received a grant of 851.0419 deferred stock units as part of his quarterly cash and equity retainers under the Southern Company 2021 Equity and Incentive Compensation Plan. Each deferred stock unit represents one share of Southern Company common stock and is deferred under the Deferred Compensation Plan for Outside Directors.

The deferred stock units, including amounts acquired through the plan’s dividend reinvestment feature, will be settled in shares of common stock after his service on the Board ends, on dates he previously specified. Following this award, his directly held deferred stock unit balance is 160,806.3288 units.

MEADOR DAVID E reported acquisition or exercise transactions in this Form 4 filing.

Southern Company director David E. Meador received a grant of 786.569 deferred stock units as quarterly board compensation. These units were awarded under the Southern Company 2021 Equity and Incentive Compensation Plan and deferred into the Deferred Compensation Plan for Outside Directors.

Each deferred stock unit represents the right to receive one share of Southern Company common stock, with settlement in shares after Meador’s board service ends, as specified in the deferral election. The grant increased his deferred stock unit holdings to 9,279.6828 units, including amounts accumulated through a dividend reinvestment feature.

Svinicki Kristine L reported acquisition or exercise transactions in this Form 4 filing.

Southern Company director Kristine L. Svinicki received a grant of 464.2047 deferred stock units as part of her quarterly director equity retainer under the Southern Company 2021 Equity and Incentive Compensation Plan. Each deferred stock unit represents the right to receive one share of Southern Company common stock.

The deferred stock units are paid into the Deferred Compensation Plan for Outside Directors and are settled in shares of common stock after she leaves the Board, according to her deferral elections. Following this award and related dividend reinvestments, she holds a total of 11,032.1291 deferred stock units.

Southern Company director Lizanne Thomas acquired additional deferred stock units as part of her board compensation. On the reported date, she received 464.2047 deferred stock units at a reference value of $96.94 per unit under the 2021 Equity and Incentive Compensation Plan. Following this grant and related dividend reinvestment, her total deferred stock unit holdings are 7,224.4488 units. These deferred stock units will be settled in shares of Southern Company common stock after her service on the Board ends, according to her elections under the Deferred Compensation Plan.

Southern Co director Dale E. Klein received a compensation grant of deferred stock units. On the reported date, he acquired 464.2047 deferred stock units at a reference value of $96.94 per unit under the Southern Company 2021 Equity and Incentive Compensation Plan.

The units are credited as a quarterly director equity retainer and are deferred pursuant to the Deferred Compensation Plan for Outside Directors. Each deferred stock unit represents the right to receive one share of Southern Company common stock, to be settled in shares after his service on the Board ends.

JAMES DONALD M reported acquisition or exercise transactions in this Form 4 filing.

Southern Company director James Donald received a grant of 464.2047 deferred stock units tied to Southern Company common stock as part of his quarterly director equity retainer. These units were awarded at a reference value of $96.94 per underlying share under the company’s 2021 Equity and Incentive Compensation Plan.

The deferred stock units will be settled in shares of common stock after his service on the Board ends, according to his elections under the Deferred Compensation Plan for Outside Directors. After this award and dividend reinvestment, his deferred stock unit balance stands at 203,293.2031 units.

Southern Company director James O. Etheredge received a grant of deferred stock units as part of his quarterly board compensation. On the reported date, he acquired 464.2047 deferred stock units tied to Southern Company common stock under the 2021 Equity and Incentive Compensation Plan.

Each deferred stock unit represents the right to receive one share of Southern Company common stock, to be settled after his service on the Board ends as specified under the Deferred Compensation Plan for Outside Directors. Following this award and dividend reinvestments, Etheredge holds a total of 2,389.7934 deferred stock units.

EARLEY ANTHONY F JR reported acquisition or exercise transactions in this Form 4 filing.

Southern Company director Anthony F. Earley Jr. received routine quarterly compensation in the form of deferred and phantom stock units. He was granted 464.2047 deferred stock units and 297.8647 phantom stock units on April 1, 2026 under the Southern Company 2021 Equity and Incentive Compensation Plan and the Deferred Compensation Plan for Outside Directors.

The deferred stock units each represent the right to receive one share of Southern Company common stock after his Board service ends, while the phantom stock units are settled in cash based on the value of one share. Following these awards, Earley holds 30,856.8400 deferred stock units and 629.0000 phantom stock units, reflecting compensation rather than open-market trading.

Southern Company director Shantella E. Cooper received a routine quarterly equity award in the form of deferred stock units. She acquired 464.2047 deferred stock units valued at $96.94 per unit, increasing her holdings to 31,867.5322 deferred stock units. Each unit will be settled in one share of Southern Company common stock after her Board service ends, under the company’s deferred compensation and equity incentive plans.

Southern Company director Janaki Akella received a grant of deferred stock units as part of board compensation. The award covered 464.2047 deferred stock units valued at $96.94 per unit, increasing Akella’s holdings to 20,534.9193 deferred stock units. Each unit represents one share of Southern Company common stock, to be settled in shares after board service ends, with no exercise or expiration date.

Southern Company executive Kimberly S. Greene, Chairman, President & CEO of GPC, sold 25,000 shares of Southern Company Common Stock in an open-market transaction. The shares were sold at $96.67 each, and she held 103,602 shares directly after the sale.

Southern Company executive vice president Christopher Cummiskey sold 6,669 shares of Southern Company Common Stock in an open-market transaction at $96.55 per share. After the sale, he directly holds 30,800.4417 shares and indirectly holds 5,857.0111 shares through a 401(k) account.

Southern Co EVP & CHRO Sloane N. Drake reported routine equity compensation activity. On March 8, 2026, the final one-third of performance restricted stock units granted on March 8, 2023 vested, resulting in 1,420 shares of Southern Company common stock, including 145 dividend equivalent units, being acquired at no cost.

To cover required state and federal taxes, 633 shares were withheld at $97.48 per share, leaving a net increase of 787 directly held shares. After these transactions, Drake directly owns 38,932 shares of common stock and indirectly holds 2,621.475 shares through a 401(k) plan. No derivative awards remain from this grant.