Page 1

Table of Contents FORM 10 - K □ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15 ( d ) OF THE SECURITIES EXCHANGE ACT OF 1934 For the Fiscal Year Ended December 31 , 2020 OR □ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15 ( d ) OF THE SECURITIES EXCHANGE ACT OF 1934 For the Transition Period from to Commission File Number 1-3526 1-3164 1-6468 001-11229 001-37803 Index to Financial Statements UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington , D.C. 20549 1-14174 Registrant , State of Incorporation , Address and Telephone Number The Southern Company ( A Delaware Corporation ) 30 Ivan Allen Jr. Boulevard , N.W. Atlanta , Georgia 30308 ( 404 ) 506-5000 Alabama Power Company ( An Alabama Corporation ) 600 North 18th Street Birmingham , Alabama 35203 ( 205 ) 257-1000 Georgia Power Company ( A Georgia Corporation ) 241 Ralph McGill Boulevard , N.E. Atlanta , Georgia 30308 ( 404 ) 506-6526 Mississippi Power Company ( A Mississippi Corporation ) 2992 West Beach Boulevard Gulfport , Mississippi 39501 ( 228 ) 864-1211 Southern Power Company ( A Delaware Corporation ) 30 Ivan Allen Jr. Boulevard , N.W. Atlanta , Georgia 30308 ( 404 ) 506-5000 Southern Company Gas ( A Georgia Corporation ) Ten Peachtree Place , N.E. Atlanta , Georgia 30309 ( 404 ) 584-4000 I.R.S. Employer Identification No. 58-0690070 63-0004250 58-0257110 64-0205820 58-2598670 58-2210952