| Boulder to Bixby (Oklahoma) | 582.71 mi (937.78 km) |
| Boulder to Black Forest (Colorado) | 73.36 mi (118.07 km) |
| Boulder to Blackfoot (Idaho) | 426.64 mi (686.62 km) |
| Boulder to Blackhawk (California) | 906.81 mi (1,459.37 km) |
| Boulder to Blacksburg (Virginia) | 1,349.33 mi (2,171.54 km) |
| Boulder to Blackwells Mills (New Jersey) | 1,608.65 mi (2,588.87 km) |
| Boulder to Blaine (Minnesota) | 707.20 mi (1,138.12 km) |
| Boulder to Bloomingdale (Florida) | 1,554.91 mi (2,502.38 km) |
| Boulder to Bloomingdale (Illinois) | 903.40 mi (1,453.88 km) |
| Boulder to Bloomington (California) | 785.52 mi (1,264.17 km) |
| Boulder to Bloomington (Illinois) | 857.97 mi (1,380.77 km) |
| Boulder to Bloomington (Indiana) | 996.98 mi (1,604.48 km) |
| Boulder to Bloomington (Minnesota) | 692.47 mi (1,114.43 km) |
| Boulder to Bloomsburg (Pennsylvania) | 1,507.27 mi (2,425.71 km) |
| Boulder to Blue Ash (Ohio) | 1,109.22 mi (1,785.12 km) |
