| Encinitas to Olympia Heights (Florida) | 2,267.49 mi (3,649.18 km) |
| Encinitas to Omaha (Nebraska) | 1,293.78 mi (2,082.14 km) |
| Encinitas to On Top of the World Designated Place (Florida) | 2,077.94 mi (3,344.13 km) |
| Encinitas to Onalaska (Wisconsin) | 1,586.41 mi (2,553.08 km) |
| Encinitas to Oneida (New York) | 2,340.08 mi (3,765.99 km) |
| Encinitas to Oneonta (New York) | 2,368.47 mi (3,811.69 km) |
| Encinitas to Ontario (California) | 71.24 mi (114.65 km) |
| Encinitas to Ontario (Oregon) | 758.57 mi (1,220.80 km) |
| Encinitas to Opa-locka (Florida) | 2,267.87 mi (3,649.78 km) |
| Encinitas to Opelika (Alabama) | 1,843.61 mi (2,967.00 km) |
| Encinitas to Opelousas (Louisiana) | 1,485.45 mi (2,390.61 km) |
| Encinitas to Orange (California) | 61.35 mi (98.74 km) |
| Encinitas to Orange (Texas) | 1,394.89 mi (2,244.86 km) |
| Encinitas to Orange City (Florida) | 2,139.12 mi (3,442.59 km) |
| Encinitas to Orangeburg (South Carolina) | 2,091.68 mi (3,366.24 km) |
