| Caguas Sporting FC | Puerto Rico Soccer League | — | 2016 | — |
| Cal FC | United States Adult Soccer Association | — | 2009 | Agoura High School |
| California Cougars | Major Arena Soccer League | — | 2004 | Adventist Health Arena |
| California Gold | USL League Two | — | 2002 | — |
| California Jaguars | USL Championship | — | 1995 | Salinas Sports Complex |
| California Storm | Women's Premier Soccer League | — | 1995 | — |
| California Sunshine | — | Fountain Valley | 1977 | — |
| California Surf | North American Soccer League | Anaheim | 1978 | Angel Stadium of Anaheim |
| California United Strikers FC | National Independent Soccer Association | Fullerton | 2017 | Titan Stadium |
| California Victory | USL First Division | San Francisco | 2006 | Kezar Stadium |
| Cape Cod Crusaders | USL League Two | Massachusetts | 1994 | Massachusetts Maritime Academy |
| Cape Coral Hurricanes | National Premier Soccer League | — | 2010 | Cape Coral High School |
| Carolina Ascent FC | USL Super League | Charlotte | — | — |
| Carolina Core FC | MLS Next Pro | High Point | 2022 | Truist Point |
| Carolina Courage | Women's United Soccer Association | Cary | 2001 | WakeMed Soccer Park |
| Carolina Lightnin' | — | Charlotte | 1981 | — |
| Carpathia FC | United Premier Soccer League | — | 1952 | — |
| Cars Plus FC | Guam Men's Soccer League | Guam | — | — |
| Cary Lady Clarets | USL W-League | — | 2007 | WakeMed Soccer Park |
| Cascade Surge | USL League Two | — | 1995 | McCulloch Stadium |
| CASL Elite | Capital Area Soccer League | — | 2009 | WakeMed Soccer Park |
| CD Aguiluchos USA | National Premier Soccer League | Oakland | 2012 | — |
| Cedar Rapids Rampage United | United Premier Soccer League | — | 2016 | — |
| Central Coast Roadrunners | USL League Two | San Luis Obispo | 1996 | Mustang Memorial Field |
| Central SC Cobras | USL W-League | — | 2010 | — |
| Charlotte Eagles | USL League Two | Charlotte | 1991 | Sportsplex at Matthews |
| Charlotte FC | Major League Soccer | Charlotte | 17 December 2019 | Bank of America Stadium |
| Charlotte Independence Soccer Club | USL League Two | Rock Hill | — | Manchester Meadows Soccer Complex |
| Charlotte Lady Eagles | USL W-League | — | 2003 | — |
| Charlottesville Alliance FC | National Premier Soccer League | Charlottesville | 2016 | Charlottesville High School |
| Charm City FC | National Premier Soccer League | — | 2007 | Arundel High School |
| Chattanooga FC | MLS Next Pro | Chattanooga | 2009 | Finley Stadium |
| Chesapeake Dragons | USL League Two | — | 2001 | Maryland SoccerPlex |
| Chesterfield United FC | National Premier Soccer League | — | 2013 | Williams Stadium |
| Chicago Americans | — | Chicago | 1972 | — |
| Chicago Cats | — | Chicago | 1975 | — |
| Chicago Croatian | National Soccer League | Chicago | 1949 | — |
| Chicago Eagles Select | USL League Two | — | 2001 | — |
| Chicago Fire FC | Major League Soccer | Chicago | 8 October 1997 | Soldier Field |
| Chicago Fire NPSL | National Premier Soccer League | — | 2007 | SeatGeek Stadium |
| Chicago Fire U-23 | USL League Two | — | 2001 | SeatGeek Stadium |
| Chicago House AC | National Independent Soccer Association | Chicago | 2020 | — |
| Chicago Inferno | USL League Two | — | 2011 | — |
| Chicago Mustangs | Major Arena Soccer League | — | 2012 | Now Arena |
| Chicago Power | National Professional Soccer League | — | 1988 | Credit Union 1 Arena |
| Chicago Red Eleven | USL W-League | — | 2005 | — |
| Chicago Riot | Major Indoor Soccer League | — | 2010 | Odeum Expo Center |
| 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 | — |
| Crystal Palace Baltimore | USSF Division 2 Professional League | Baltimore | 2006 | — |
| CT United FC | MLS Next Pro | Bridgeport | 9 January 2024 | — |
| CT United FC | — | — | 2015 | Veterans Stadium |