| Southborough to Brownsburg (Indiana) | 4,020.61 mi (6,470.54 km) |
| Southborough to Brownsville (Florida) | 4,448.35 mi (7,158.93 km) |
| Southborough to Brownsville (Texas) | 5,153.92 mi (8,294.44 km) |
| Southborough to Brownwood (Texas) | 4,913.23 mi (7,907.07 km) |
| Southborough to Brunswick (Georgia) | 4,236.59 mi (6,818.13 km) |
| Southborough to Brunswick (Ohio) | 3,776.48 mi (6,077.65 km) |
| Southborough to Brushy Creek (Texas) | 4,927.91 mi (7,930.71 km) |
| Southborough to Bryan (Texas) | 4,866.82 mi (7,832.40 km) |
| Southborough to Bryant (Arkansas) | 4,512.78 mi (7,262.62 km) |
| Southborough to Bryn Mawr-Skyway (Washington) | 4,817.62 mi (7,753.22 km) |
| Southborough to Buckeye (Arizona) | 5,318.38 mi (8,559.11 km) |
| Southborough to Buckhall (Virginia) | 3,713.42 mi (5,976.18 km) |
| Southborough to Bucyrus (Ohio) | 3,841.88 mi (6,182.91 km) |
| Southborough to Buda (Texas) | 4,955.03 mi (7,974.36 km) |
| Southborough to Buena Park (California) | 5,472.60 mi (8,807.31 km) |
