X0306 4 2021-02-11 0 0000092122 SOUTHERN CO SO 0001498337 Connally Stan W 30 IVAN ALLEN JR. BLVD ATLANTA GA 30308 0 1 0 0 Executive Vice President, SCS Southern Company Common Stock 2021-02-11 4 M 0 2726 0.00 A 47895 D Southern Company Common Stock 2021-02-11 4 F 0 1210 61.29 D 46685 D Southern Company Common Stock 12292.9759 I By 401(k) Performance Restricted Stock Units 0.00 2021-02-11 4 M 0 2502 0.00 D Southern Company Common Stock 2502 2503 D Shares acquired upon vesting of second 1/3 of performance restricted stock units granted on February 11, 2019. Includes 224 accrued dividend equivalent units. Shares withheld to satisfy required state and federal tax withholding requirements. Represents performance restricted stock units granted on February 11, 2019. The remaining 1/3 of the award will vest in 2022. Each performance restricted stock unit represents the right to receive, at statement, one share of common stock. Additional units will be acquired with deemed dividends. Shares will be withheld upon vesting to satisfy tax requirements. /s/ Marcia R. DeMar, Attorney-in-Fact for Stan W. Connally 2021-02-16