| Ontario to Carrollwood (Florida) | 2,107.29 mi (3,391.36 km) |
| Ontario to Carson (California) | 39.76 mi (63.99 km) |
| Ontario to Carson City (Nevada) | 372.59 mi (599.63 km) |
| Ontario to Carteret (New Jersey) | 2,401.48 mi (3,864.81 km) |
| Ontario to Cartersville (Georgia) | 1,868.66 mi (3,007.32 km) |
| Ontario to Carthage (Missouri) | 1,322.27 mi (2,127.98 km) |
| Ontario to Cary (Illinois) | 1,682.59 mi (2,707.87 km) |
| Ontario to Cary (North Carolina) | 2,186.61 mi (3,519.01 km) |
| Ontario to Casa de Oro-Mount Helix (California) | 95.48 mi (153.66 km) |
| Ontario to Casa Grande (Arizona) | 345.72 mi (556.39 km) |
| Ontario to Casas Adobes (Arizona) | 398.86 mi (641.91 km) |
| Ontario to Cascades (Virginia) | 2,240.79 mi (3,606.21 km) |
| Ontario to Casper (Wyoming) | 860.43 mi (1,384.73 km) |
| Ontario to Casselberry (Florida) | 2,161.52 mi (3,478.63 km) |
| Ontario to Castaic (California) | 66.05 mi (106.29 km) |
