Girls' Fast Pitch Class “A” – Any team considered to be a higher competitive level travel team within Illinois. This team has the higher skill level to compete in the Class A Division of the World Series/National Tournament. Also, any team that participates in another association as Class “A” must play this classification in USSSA.

Girls' Fast Pitch Class “B” – These teams may lack the experience and number of skilled players and pitchers to compete on a National or State level with the higher skilled Class “A” teams. This classification may be for the first year team in their age group. As of the 2012 season– Class “B” teams are allowed up to 3 former Class “A” players to their roster. Only one of these 3 additions can be a former Class “A” pitcher. These teams will be monitored closely by the Roster Managers. Note: Adding any “A” player to an already strong “B” team may result in a reclassification to “A” for the entire season.

Girls' Fast Pitch Class “C” – This program is limited to any team that might have limited tournament experience and has no more than 2 former Class “B” players and no Class “A” players on the roster. Also, these teams would not be very competitive in the Class “B” program. And, the program is open to In House League player/team or All Star League team/players. This is a restricted program and any team that does not meet the requirements will not be allowed to participate. 

Any team or organization registered and classified by any other softball sanctioning body (i.e. ASA, NAFA, USFA ect.) with a USSSA equivalent "A" or "B" classification; will be denied participation in NISA.