| North Branch to Olympia Heights (Florida) | 1,535.80 mi (2,471.62 km) |
| North Branch to Omaha (Nebraska) | 332.18 mi (534.59 km) |
| North Branch to On Top of the World Designated Place (Florida) | 1,273.75 mi (2,049.89 km) |
| North Branch to Onalaska (Wisconsin) | 141.49 mi (227.70 km) |
| North Branch to Oneida (New York) | 870.05 mi (1,400.21 km) |
| North Branch to Oneonta (New York) | 912.23 mi (1,468.10 km) |
| North Branch to Ontario (California) | 1,520.79 mi (2,447.47 km) |
| North Branch to Ontario (Oregon) | 1,178.09 mi (1,895.95 km) |
| North Branch to Opa-locka (Florida) | 1,526.83 mi (2,457.19 km) |
| North Branch to Opelika (Alabama) | 975.60 mi (1,570.08 km) |
| North Branch to Opelousas (Louisiana) | 1,036.69 mi (1,668.39 km) |
| North Branch to Orange (California) | 1,540.62 mi (2,479.38 km) |
| North Branch to Orange (Texas) | 1,064.30 mi (1,712.83 km) |
| North Branch to Orange City (Florida) | 1,310.00 mi (2,108.24 km) |
| North Branch to Orangeburg (South Carolina) | 1,048.90 mi (1,688.05 km) |
