SUBJECT TO COMPLETION vi d PRELIMINARY PROSPECTUS SUPPLEMENT DATED OCTOBER I.2015 eu PROSPECTUS SUPPLEMENT ^.= .— (To Prospectus dated March 2. 2015) ria cn = H O o alt " SOUTHERN Vs a = COMPANY c▪ a G3 = V7 Series 2015A % Junior Subordinated Notes G3 a ! en 7.5 due October 15, 2075 = = O te • a` E lad .= EFtc • c 0. 0 a) O 0 0. ▪ r, Jr.v, zo 4, ?= t Tot •a• a) G, /3) E 0 = CD cal 0.6 O. 0 CD ^ y a) a)NL • = 3 Tu e_ o.. Initial public offering price (I) = o P "t3 ▪ it 12 mien% riting discount (2) co .02 a a. Proceeds. he expenses. to the Southern Company (2) ra '= E = y,_ • V) CO viz._ E O 0= • co 0.0 ca and ▪ C E 2 .2 I= a. CT, •••• >.. 0 = 03 E e m9 0 o. co = u) . — s The Series 20I5A °/• Junior Subordinated Notes due October 15.2075 will bear interest at a fixed raw of %per year. Interest will be payable quarterly in arrears on January IS. April 15. July 15 and October IS of each year. beginning on January I5.2016. The Series 2015A Junior Subordinated Notes will be issued in registered form and in denominations of $25.00 and integral multiples of $25.00 in excess thereof. The Series 2015A Junior Subordinated Notes will mature on October I5.2075. So long as no Event of Default has occurred and is continuing. The Southern Company may defer interest payments on the Series 2015A Junior Subordinated Notes on one or more occasions for up to 40 consecutive quarterly periods as described in this Prospectus Supplement. Deferred interest payments will accrue additional interest at a rate equal to the interest rate then applicable to the Series 2015A Junior Subordinated Notes. compounded quarterly. to the extent permitted by applicable law. The Southern Company may redeem the Series 2015A Junior Subordinated Notes at its option at the times and the prices described in this Prospectus Supplement. The Series 20I5A Junior Subordinated Notes are a new issue of securities with no e