| Ontario to Cordele (Georgia) | 1,957.19 mi (3,149.79 km) |
| Ontario to Corinth (Mississippi) | 1,652.03 mi (2,658.69 km) |
| Ontario to Corinth (Texas) | 1,181.72 mi (1,901.79 km) |
| Ontario to Cornelius (North Carolina) | 2,075.07 mi (3,339.50 km) |
| Ontario to Cornelius (Oregon) | 843.68 mi (1,357.77 km) |
| Ontario to Corning (New York) | 2,252.45 mi (3,624.97 km) |
| Ontario to Corona (California) | 12.51 mi (20.13 km) |
| Ontario to Coronado (California) | 98.39 mi (158.34 km) |
| Ontario to Corpus Christi (Texas) | 1,273.69 mi (2,049.80 km) |
| Ontario to Corsicana (Texas) | 1,229.38 mi (1,978.49 km) |
| Ontario to Cortland (New York) | 2,297.71 mi (3,697.80 km) |
| Ontario to Corvallis (Oregon) | 787.73 mi (1,267.72 km) |
| Ontario to Coshocton (Ohio) | 2,001.38 mi (3,220.91 km) |
| Ontario to Costa Mesa (California) | 31.20 mi (50.21 km) |
| Ontario to Coto de Caza (California) | 30.66 mi (49.34 km) |
