The A-Sun Championship was a four-day single-elimination tournament. The top eight teams (with the exception of Northern Kentucky) competed in the championship. As part of their transition to Division I from Division II, Northern Kentucky was not eligible for post season play until 2017, including the A-Sun tournament. The winner of the tournament earned the A-Sun's automatic bid into the 2013 NCAA tournament.
Defending champion Belmont was not in the tournament, as they moved to the Ohio Valley Conference for the 2012-13 season.