| Cloud City Wheelers | Leadville | Club |
| Club Mud | Ft. Lauderdale Area | Club |
| Club Scrub | Treasure Coast - Palm Beach, Martin & St Lucie Counties | Club |
| Club Tread | South Florida | Club |
| CNY Dedicated Individuals for Responsible Trail-use (DIRT) | North Syracuse | Club |
| Coalition of Arizona Bicyclists | Phoenix | Club |
| COGS Mountain Bike Club | Ft. Campbell, KY/ Clarksville, TN | Club |
| Cold Creek Mountain Bikers | Battleground | Club |
| Collin County BOMB | | Club |
| Colorado Mountain Bike Association (COMBA) | Lakewood | Club |
| Colorado Plateau Mountain Bike Trail Association (COPMOBA) | Grand Junction | Club |
| Colorado Springs BOMB | Colorado Springs | Club |
| Colorado Youth Program | Boulder | Club |
| Columbia County Mountain Bike Alliance (CCMBA) | Columbia County | Club |
| Columbia Land Conservancy | Chatham | Club |
| Community Bicycle Center | Biddeford | Club |
| Concerned Off-Road Bicyclists Association (CORBA) | Los Angeles | Club |
| Connecticut NEMBA | | Club |
| Contagious Mountain Bike Club (CMBC) | Whitehorse | Club |
| Coos Cycling Club | | Club |
| Copper Harbor Trails Club | Upper Peninsula - Keweenaw Peninsula | Club |
| CORBA-Comlara Off Road Bicycling Assn. | Bloomington/Normal | Club |
| CORBA: Chippewa Off Road Bike Association | Eau Claire | Club |
| Cosmo's Factory | Pasadena/Burbank | Club |
| Country Road Cyclists | Clarksburg | Club |
