| Ontario to Cloverleaf (Texas) | 1,345.17 mi (2,164.85 km) |
| Ontario to Cloverly (Maryland) | 2,261.27 mi (3,639.16 km) |
| Ontario to Clovis (California) | 225.34 mi (362.66 km) |
| Ontario to Clovis (New Mexico) | 823.09 mi (1,324.64 km) |
| Ontario to Clute (Texas) | 1,349.96 mi (2,172.55 km) |
| Ontario to Coachella (California) | 87.35 mi (140.57 km) |
| Ontario to Coalinga (California) | 211.44 mi (340.28 km) |
| Ontario to Coamo (Puerto Rico) | 3,328.67 mi (5,356.97 km) |
| Ontario to Coatesville (Pennsylvania) | 2,320.13 mi (3,733.89 km) |
| Ontario to Cockeysville (Maryland) | 2,279.30 mi (3,668.18 km) |
| Ontario to Cocoa (Florida) | 2,199.69 mi (3,540.06 km) |
| Ontario to Cocoa Beach (Florida) | 2,208.86 mi (3,554.82 km) |
| Ontario to Coconut Creek (Florida) | 2,285.53 mi (3,678.21 km) |
| Ontario to Coeur d'Alene (Idaho) | 945.08 mi (1,520.96 km) |
| Ontario to Cohoes (New York) | 2,423.22 mi (3,899.80 km) |
