| Chicago Sockers | USL League Two | Chicago | 1995 | — |
| Chicago Soul FC | Major Indoor Soccer League | — | 2011 | Now Arena |
| Chicago Spurs | National Professional Soccer League | Chicago | 1966 | Soldier Field |
| Chicago Stars FC | National Women's Soccer League | Chicago | 2006 | SeatGeek Stadium |
| Chicago Sting | North American Soccer League | Chicago | 1974 | Soldier Field |
| Chicago Storm | Major Indoor Soccer League | — | 2004 | — |
| Chicago United Breeze | Women's Premier Soccer League | — | 2006 | — |
| Chico Rooks | National Premier Soccer League | Chico | 1993 | University Soccer Stadium, Chico |
| Chivas USA | Major League Soccer | Los Angeles | 2004 | Dignity Health Sports Park |
| Christos FC | — | Baltimore | 1997 | — |
| Chula Vista FC | SoCal Premier League | Chula Vista | 2011 | Eastlake High School |
| Cincinnati Cheetahs | United Soccer League, USL Second Division | — | 1994 | RDI Stadium |
| Cincinnati Comets | American Soccer League | Cincinnati | 1972 | Nippert Stadium |
| Cincinnati Dutch Lions | USL League Two | — | 2013 | — |
| Cincinnati Kids | Major Indoor Soccer League | Cincinnati | 1978 | — |
| Cincinnati Kings Indoor Team | Major Arena Soccer League | — | 2008 | — |
| Cincinnati Riverhawks | USL League Two | — | 1997 | — |
| Cincinnati Silverbacks | National Professional Soccer League | — | 1995 | — |
| City of Angels FC | — | San Fernando Valley | 2017 | — |
| Claremont Stars | Women's Premier Soccer League | — | 2006 | — |
| Cleveland City Stars | USL First Division | Cleveland | 2006 | Middlefield Cheese Stadium |
| Cleveland Cobras | — | Cleveland | 1972 | — |
| Cleveland Crunch | — | — | 1989 | Coliseum at Richfield |
| Cleveland Force SC | — | Cleveland | 2018 | — |
| Cleveland Internationals | USL League Two | — | 2004 | — |
| Cleveland SC | National Premier Soccer League | Cleveland | 2018 | Don Shula Stadium |
| Cleveland Stokers | North American Soccer League | Cleveland | 1967 | Cleveland Stadium |
| Club de Fútbol Fraigcomar | Puerto Rico Soccer League | — | 1986 | — |
| Cocoa Expos | USL League Two | Cocoa | 1993 | — |
| Colombo | — | New York City | 1959 | — |
| Colorado Crimson | National Premier Soccer League | — | 2007 | — |
| Colorado Foxes | A-League | — | 1990 | — |
| Colorado Lightning | Major Arena Soccer League | — | 2008 | Blue Arena |
| Colorado Predators | Premier Arena Soccer League | — | 2007 | — |
| Colorado Pride | — | — | 1994 | Washburn Field |
| Colorado Rapids | Major League Soccer | Commerce City | 1995 | Dick's Sporting Goods Park |
| Colorado Rapids U-23 | USL League Two | — | 2000 | Dick's Sporting Goods Park |
| Colorado Rapids Women | USL W-League | — | 1996 | Dick's Sporting Goods Park |
| Colorado Springs Ascent | USL League Two | — | 2000 | Switchbacks Training Stadium |
| Colorado Springs Blizzard | USL League Two | — | 2004 | Switchbacks Training Stadium |
| Colorado Springs Switchbacks FC | USL Championship | Colorado Springs | 2013 | Switchbacks Training Stadium |
| Columbus Magic | American Soccer League | Columbus | 1979 | — |
| Columbus NWSL team | National Women's Soccer League | Columbus | 21 April 2026 | — |
| Columbus Shooting Stars | USL League Two | — | — | Historic Crew Stadium |
| Connecticut Bicentennials | North American Soccer League | Hartford | 1975 | Yale Bowl, Trinity Health Stadium |
| Connecticut Wolves | A-League | — | 1993 | — |
| Connecticut Yankees | American Soccer League | Hartford | 1972 | Trinity Health Stadium |
| Croatian Eagles | United Premier Soccer League | — | 1922 | — |