The Southern League (SL) is a Minor League Baseball league that operates in the United States at the Double-A level, which is two grades below Major League Baseball. A champion has been determined at the end of each season since the league was formed in 1964.
Through 1970, champions were the regular-season pennant winners—the team with the best win–loss record at the conclusion of the regular season. The 1971 title was decided in a postseason series between the two teams with the best records. From 1972 to 1975, the winners of each of two divisions competed in a series to determine champions. The league operated using a split season format from 1976 to 2020. Under this format, the winners of each half within each division played for the division championship, and the division winners met to play for the SL title. The 2021 winner was crowned via a series between the two teams with the best full-season records. As of 2022, the winners of each division from both the first and second halves of the season meet in a best-of-three division series, with the winners of the two division series meeting in a best-of-three championship series.
The Birmingham Barons have won eight Southern League championships, more than any other team, followed by the Jacksonville Suns (6) and Montgomery Rebels (5). Among active SL franchises, Birmingham has won seven championships, the most of all teams, followed by the Knoxville Smokies (4) and Chattanooga Lookouts (3).