;Active On August 18, 2022,
Chicago (Mustangs),
Cleveland Crunch, and Grand Rapids (Rapid City FC) were announced as charter teams. Former NISL team Central Florida Crusaders relocated to
Toronto and joined the MLIS ahead of the 2024-25 season as the
Canadian Crusaders, the league's first team based outside the United States.
Panathinaikos Chicago would join the MLIS for the 2024-25 season, though they would not return for 2025-26. The league expanded to 13 teams for the 2025-26 season with the addition of Atlético Pro FC, Dallas CD La Cuadra, Boulder United FC Halo, Las Vegas Turf Monsters, Utah Uprising FC,
Bridge City FC, and Rockford Thunder. The league would be redivided into two conferences, North and South. ;Inactive ==Women's teams==