| Stade Brestois New York | — | Queensbridge | 2011 | — |
| Staten Island Vipers | A-League | Staten Island | 1998 | Tottenville High School |
| Stix, Baer and Fuller F.C. | — | St. Louis | 1929 | — |
| Strykers F.C. | Guam Men's Soccer League | Tamuning | — | — |
| Stumptown AC | National Independent Soccer Association | Matthews | 2018 | Sportsplex at Matthews |
| SW Florida Adrenaline | USL League Two | — | 2012 | Estero High School |
| Syracuse FC | National Premier Soccer League | Syracuse | 2017 | — |
| Syracuse Salty Dogs | A-League | — | 2003 | Alliance Bank Stadium |
| Syracuse Suns | — | Syracuse | 1969 | — |
| Tacoma Stars | Major Arena Soccer League | — | 2003 | accesso ShoWare Center |
| Tacoma Stars | Major Indoor Soccer League | — | 1983 | — |
| Tallahassee Scorpions | Eastern Indoor Soccer League | — | 1997 | Donald L. Tucker Civic Center |
| Tallahassee Tempest | — | Tallahassee | 1998 | — |
| Tampa Bay Hawks | USL League Two | — | 2000 | — |
| Tampa Bay Mutiny | Major League Soccer | — | 1995 | Raymond James Stadium |
| Tampa Bay Rowdies | North American Soccer League | — | 1975 | Tampa Stadium |
| Tan Holdings FC | M*League Division 1 | — | 2008 | Ada Gym |
| Team Hawaii | North American Soccer League | Honolulu | 1977 | Aloha Stadium |
| Tebo Yacht Basin F.C. | — | New York City | 1918 | — |
| Temecula FC | National Premier Soccer League | Temecula | 2013 | Chaparral High School |
| Temple United FC | Texas Premier Soccer League | — | 11 March 2015 | — |
| Texas Outlaws | Major Arena Soccer League | — | 2008 | — |
| The Island F.C. | MLS Next Pro | Uniondale | 2025 | — |
| Tobacco Road FC | USL League Two | — | 2013 | Durham County Stadium |
| Todd Shipyards | American Soccer League | New York City | 1921 | — |
| Toledo Slayers | USL League Two | — | 2003 | Lucas County Recreation Center |
| Toledo United FC | Great Lakes Premier League | — | 2016 | Springfield Local High School |
| Tormenta FC | USL League One | Statesboro | 2015 | Bo Pitts Field |
| Tornados de Humacao | Puerto Rico Soccer League | Humacao | 1994 | Nestor Morales Stadium |
| Toronto FC | Major League Soccer | Toronto | 2006 | BMO Field |
| Treasure Coast Tritons | USL League Two | Port St. Lucie | 2016 | — |
| Tucson Amigos | United Soccer League | Arizona | 1989 | — |
| Tucson Extreme | Major Arena Soccer League | — | 2012 | Tucson Convention Center |
| Tucson Fireballs | — | Arizona | 1997 | — |
| Tucson Tiburons | National Premier Soccer League | Arizona | 2003 | Mountain View High School |
| Tulsa Revolution | Major Arena Soccer League | — | 2012 | Arvest Convention Center |
| Tulsa Roughnecks | North American Soccer League | Tulsa | 1978 | Skelly Field at H. A. Chapman Stadium |
| Tulsa Roughnecks | — | Tulsa | 1993 | — |
| Tulsa Spirit | Women's Premier Soccer League | — | 2007 | — |
| Turlock Express | Major Arena Soccer League 2, Major Arena Soccer League | Turlock | 2011 | — |
| Twin Cities Phoenix | USL League Two | — | 1997 | — |
| Tyler FC | National Premier Soccer League | Tyler | 2016 | Brook Hill School |
| Uhrik Truckers | American Soccer League | Philadelphia | 1933 | — |
| Ukrainian Sports Club NY | Cosmopolitan Soccer League | — | 1947 | — |
| Union Omaha | USL League One | Omaha | 2019 | — |
| Unique FC | St Croix Soccer League | — | 1970 | — |
| USL Chicago | USL Championship | Chicago | 21 November 2017 | Lincoln Yards Stadium |
| Utah Blitzz | USL Second Division | Salt Lake City | 2000 | Rice–Eccles Stadium |