In Boulder County, transit service is provided by a number of operators:
Transit Service Operated by Boulder County:
- Ride Free Lafayette – Free on-demand transit service within Lafayette
- Lyons Taxi Voucher Program – Taxi vouchers for travel between Lyons-Boulder or Lyons-Longmont
- Lyons Flyer – Commuter bus service between Lyons and Boulder
- Gold Hill Climb – Commuter bus service between Gold Hill-Salina-Fourmile-Boulder
- Hessie Shuttle – Free summer weekend shuttle service to Hessie Trailhead from Nederland
- Eldo Shuttle – Free summer weekend shuttle service from Boulder, Superior, and Marshall to Eldorado Canyon State Park
- Boulder Canyon Extra – Temporary free bus service between Nederland and Boulder until January 17, 2025
Transit Service Operated by City of Boulder
- HOP route
- Park-to-Park – Summer weekend shuttle service to Chautauqua from downtown Boulder and CU-Boulder
Transit Service Operated by City of Ft. Collins
- FLEX Express – Express bus service between Boulder-Longmont-Loveland-Ft. Collins
Transit Service Operated by RTD
- Local routes within the City of Boulder including the SKIP, BOUND, 204, 206
- Local routes connecting cities within Boulder County, including DASH, JUMP, 205, 225, 228
- Local routes within the City of Longmont, including 323, 324, 326, 327
- Regional routes connecting cities in Boulder County and beyond: BOLT, LD, NB
- Flatiron Flyer-Bus Rapid Transit between Boulder-Louisville-Superior-Broomfield-Westminster-Denver
- AB Boulder-DIA Airport Bus
- Access-a-Ride – Transportation assistance to passengers with disabilities who are unable to use regular buses and qualify under American Disability Act (ADA) guidelines
Transit Service Operated by CDOT
- Estes Park Bustang – Summer weekend bus service between Denver-Boulder-Lyons-Estes Park-Rocky Mountain National Park
