| Icon FC | American Soccer League | — | 2010 | — |
| Idaho Wolves | National Premier Soccer League | — | 2004 | — |
| IFC Wild Bills | M*League Division 1 | — | 2007 | Oleai Sports Complex |
| Illinois Piasa | Major Arena Soccer League | — | 2007 | — |
| IMG Academy Bradenton | USL League Two | Bradenton | 1998 | — |
| Indiana Blaze | USL W-League | — | 1997 | Kuntz Stadium |
| Indiana Invaders | USL League Two | — | 1998 | Indiana Invaders Soccer Complex |
| Indianapolis Braves | National Premier Soccer League | — | 2007 | — |
| Indianapolis Daredevils | — | Indianapolis | 1974 | — |
| Indios USA | — | — | 2007 | Canutillo Stadium |
| Indy Eleven | USL Championship | Indianapolis | 2013 | IU Michael A. Carroll Track & Soccer Stadium |
| Inter Miami CF | Major League Soccer | Miami | January 29, 2018 | Chase Stadium |
| Inter Nashville FC | National Premier Soccer League | Nashville | — | — |
| Isabela Soccer Club | Liga Nacional de Fútbol de Puerto Rico | — | 2011 | — |