| Mason City to Brown Deer (Wisconsin) | 263.28 mi (423.71 km) |
| Mason City to Brownsburg (Indiana) | 420.41 mi (676.59 km) |
| Mason City to Brownsville (Florida) | 1,402.51 mi (2,257.13 km) |
| Mason City to Brownsville (Texas) | 1,209.10 mi (1,945.85 km) |
| Mason City to Brownwood (Texas) | 850.79 mi (1,369.22 km) |
| Mason City to Brunswick (Georgia) | 1,048.89 mi (1,688.02 km) |
| Mason City to Brunswick (Ohio) | 596.63 mi (960.18 km) |
| Mason City to Brushy Creek (Texas) | 908.04 mi (1,461.35 km) |
| Mason City to Bryan (Texas) | 880.07 mi (1,416.34 km) |
| Mason City to Bryant (Arkansas) | 590.83 mi (950.85 km) |
| Mason City to Bryn Mawr-Skyway (Washington) | 1,433.56 mi (2,307.10 km) |
| Mason City to Buckeye (Arizona) | 1,245.30 mi (2,004.12 km) |
| Mason City to Buckhall (Virginia) | 875.52 mi (1,409.02 km) |
| Mason City to Bucyrus (Ohio) | 549.31 mi (884.03 km) |
| Mason City to Buda (Texas) | 938.91 mi (1,511.03 km) |
