- Basalt (Population: 2,681)
- Battlement Mesa (Population: 3,497)
- Bayfield (Population: 1,549)
- Bennett (Population: 2,021)
- Berkley (Population: 10,743)
- Berthoud (Population: 4,839)
- Beulah Valley (Population: 1,164)
- Black Forest (Population: 13,247)
- Boulder (Population: 94,673)
- Breckenridge (Population: 2,408)
- Brighton (Population: 20,905)
- Broomfield (Population: 38,272)
- Brush (Population: 5,117)
- Buena Vista (Population: 2,195)
- Burlington (Population: 3,678)
- Byers (Population: 1,233)
