Unofficial invitational state tournaments were held from 1912 to 1922. Four teams were invited to the initial tournament and eight to the next seven tournaments. From 1920 to 1922 there were two state tournaments held, one in Ames (with 16 teams) and one in Iowa City (with 8). 

In 1923 and 1924 a four-team round-robin state tournament was held following sectional and district tournaments. In 1925 and 1926, the same format was used, but with two tournaments, one for Class A schools and another for Class B schools. In 1927, classifications were eliminated and the tournament format was changed, with 8 teams qualifying for a single-elimination state tournament following sectional and district play. In 1930, A and B classes were re-instituted, but used only for sectional and district tournaments, so that 8 Class A and 8 Class B teams would qualify to battle it out in a single 16 team state tournament. With the exception of the war years, this format continued through 1954. In 1955, the tournament was cut to 8 teams regardless of classification. Then, in 1956, two tournaments were again held, consisting of 8 teams each. From 1961 to 1966, there was again a single tournament without classes, but 1967 saw the return of a two class format. This was increased to three classes in 1975, and in 1985 the smallest classification was split in half to increase the number to four classes. Every tournament since the final single-class tournament has featured 8 teams qualifying for state. 

The tournament has been held at Wells Fargo Arena in Des Moines since 2006, after previously being held at Veterans Memorial Auditorium in Des Moines every year from 1955 to 2005.