| South Portland to Blue Island (Illinois) | 892.65 mi (1,436.58 km) |
| South Portland to Blue Springs (Missouri) | 1,279.76 mi (2,059.58 km) |
| South Portland to Bluffdale (Utah) | 2,125.35 mi (3,420.41 km) |
| South Portland to Bluffton (Indiana) | 786.46 mi (1,265.69 km) |
| South Portland to Bluffton (South Carolina) | 977.37 mi (1,572.92 km) |
| South Portland to Blythe (California) | 2,459.02 mi (3,957.41 km) |
| South Portland to Blytheville (Arkansas) | 1,165.49 mi (1,875.68 km) |
| South Portland to Boca Raton (Florida) | 1,313.10 mi (2,113.22 km) |
| South Portland to Boerne (Texas) | 1,829.22 mi (2,943.85 km) |
| South Portland to Bogalusa (Louisiana) | 1,389.62 mi (2,236.38 km) |
| South Portland to Boiling Springs (South Carolina) | 859.83 mi (1,383.77 km) |
| South Portland to Boise (Idaho) | 2,267.91 mi (3,649.85 km) |
| South Portland to Bolingbrook (Illinois) | 913.12 mi (1,469.53 km) |
| South Portland to Bolivar (Missouri) | 1,277.39 mi (2,055.76 km) |
| South Portland to Bon Air (Virginia) | 569.09 mi (915.87 km) |
