| Billings to Oerlinghausen | 4,726.24 mi (7,606.14 km) |
| Billings to Oestrich-Winkel | 4,808.26 mi (7,738.15 km) |
| Billings to Offenburg | 4,885.54 mi (7,862.51 km) |
| Billings to Oftersheim | 4,858.15 mi (7,818.44 km) |
| Billings to Ohrdruf | 4,844.05 mi (7,795.75 km) |
| Billings to Ohringen | 4,894.09 mi (7,876.27 km) |
| Billings to Olbernhau | 4,924.96 mi (7,925.96 km) |
| Billings to Olching | 5,000.27 mi (8,047.15 km) |
| Billings to Oldenburg | 4,653.15 mi (7,488.53 km) |
| Billings to Oldenburg in Holstein | 4,666.25 mi (7,509.61 km) |
| Billings to Olfen | 4,702.25 mi (7,567.54 km) |
| Billings to Olpe | 4,751.08 mi (7,646.13 km) |
| Billings to Olsberg | 4,752.76 mi (7,648.83 km) |
| Billings to Oranienburg | 4,810.19 mi (7,741.26 km) |
| Billings to Ortenberg | 4,820.75 mi (7,758.25 km) |
