The Southern Indoor Football League (SIFL) was an indoor football league based in the Southern and Eastern United States. The most recent incarnation of the league was a consolidation of an earlier league of the same name that was formed by Thom Hager along with Dan Blum, Robert Winfrey and Dan Ryan in 2009 and the American Indoor Football Association, which traces its roots to the founding of the Atlantic Indoor Football League in 2005. The SIFL broke up into three regional leagues after the 2011 season.