| Bike Utah | Salt Lake City | Club |
| Bike Works | Seattle | Club |
| Billings Bicycle Club | Billings | Club |
| Birmingham Urban Mountain Pedalers (BUMP) | Birmingham | Club |
| Black Hills Mountain Bike Association - BHMBA | Rapid City | Club |
| Blackhawk Bicycle & Ski Club | Rockford | Club |
| Blackstone Valley NEMBA | Blackstone Valley, South Central Mass | Club |
| Blue Ridge Cyclery Racing | Charlottesville | Club |
| Bluedog Cycles | Viroqua | Club |
| Boise BOMB | Boise | Club |
| Bonneville Cycling Club | Bonneville | Club |
| Boone Area Cyclists | Boone | Club |
| Borderland Mountain Bike Association (BMBA) | El Paso | Club |
| Borderline Ozark Off-Road Cyclists | Siloam Springs | Club |
| Boulder Mountainbike Alliance (BMA) | Boulder, CO | Club |
| Bowling Green League of Bicyclists (BGLOB) | Bowling Green | Club |
| Brazos Valley Mountain Bike Association (BVMBA) | College Station | Club |
| Brevard Mountain Bike Association (BMBA) | Palm Bay/Melbourne FL | Club |
| Brimfield Trail Committee | Brimfield | Club |
| Brooklyn Mountain Biking (BKMTB) | Brooklyn | Club |
| Brushy Mountain Cycling Club (BMCC) | North Wilkesboro | Club |
| C.L.I.M.B. (Concerned Long Island Mountain Bikers) | Long Island | Club |
| California Mountain Biking Coalition | California | Club |
| California Mountain Biking Coalition | California | Club |
| CAMBA | Central Adirondacks | Club |
