The season began on 3 August 2012 and ended with the last games on 19 May 2013, with a winter break held between the weekends around 15 December 2012 and 2 February 2013.
At the end of the 2011–12 season, SpVgg Greuther Fürth and Eintracht Frankfurt were directly promoted to the 2012–13 Bundesliga.
Aachen dropped to the third tier for the first time since the 1998–99 season, while Rostock concluded a cameo appearance in the league.
Liga champions SV Sandhausen and runners-up VfR Aalen, who earned direct promotion spots are thus both made their debut on this level of the league system.
However, this decision is provisional since Hertha have appealed the result of the second leg, which was marred by several incidents of crowd disturbance.
Following their promotion, Aalen, Jahn Regensburg and Sandhausen all increased the capacity of their stadiums to 12,500, 13,251 and 12,100 spectators, respectively.
[7] Elsewhere, St. Pauli's Millerntor-Stadion was undergoing reconstruction during the autumn as the entire Back Straight was being rebuilt.
[9] An additional three clubs will have a slightly decreased capacity, as Eintracht Braunschweig, FSV Frankfurt and Union Berlin all are rebuilding a stand of their stadiums.