The 1911–12 Southern Football League season was the 18th in the history of the Southern League. Queens Park Rangers won their second league championship (the first being in 1907–08), but no clubs applied to join the Football League. Luton Town, who finished second bottom of Division One were relegated to Division Two, whilst Leyton, who finished bottom, left the Southern League after 7 seasons of participation to join the South Essex League.
Merthyr Town won the Division Two championship and were promoted to Division One together with runners-up Portsmouth, who returned to Division One after one season of absence. Walsall, who also played in the Birmingham & District League, left the Southern League, but continued to play in the Birmingham & District League. Kettering also left the Southern League along with Cwm Albion and Chesham Town, who became a founder member of the Athenian League.
Source: rsssf.com Rules for classification: The system of using goal average to separate two teams tied on points was used until the 1976–77 season. The points system: 2 points for a win, 1 point for a draw and 0 points for losing. Notes:
Source: rsssf.com Rules for classification: The system of using goal average to separate two teams tied on points was used until the 1976-77 season. The points system: 2 points for a win, 1 point for a draw and 0 points for losing. Note: Number of goals for and/or against is inaccurate. Notes: