| Mobile to Olympia Heights (Florida) | 584.05 mi (939.93 km) |
| Mobile to Omaha (Nebraska) | 854.54 mi (1,375.25 km) |
| Mobile to On Top of the World Designated Place (Florida) | 365.66 mi (588.47 km) |
| Mobile to Onalaska (Wisconsin) | 928.22 mi (1,493.83 km) |
| Mobile to Oneida (New York) | 1,096.36 mi (1,764.42 km) |
| Mobile to Oneonta (New York) | 1,086.65 mi (1,748.80 km) |
| Mobile to Ontario (California) | 1,730.73 mi (2,785.34 km) |
| Mobile to Ontario (Oregon) | 1,819.85 mi (2,928.77 km) |
| Mobile to Opa-locka (Florida) | 580.89 mi (934.85 km) |
| Mobile to Opelika (Alabama) | 211.45 mi (340.30 km) |
| Mobile to Opelousas (Louisiana) | 236.05 mi (379.88 km) |
| Mobile to Orange (California) | 1,743.31 mi (2,805.58 km) |
| Mobile to Orange (Texas) | 338.52 mi (544.80 km) |
| Mobile to Orange City (Florida) | 426.63 mi (686.60 km) |
| Mobile to Orangeburg (South Carolina) | 466.64 mi (750.99 km) |
