| Ontario to Johnstown (Pennsylvania) | 2,155.71 mi (3,469.28 km) |
| Ontario to Joliet (Illinois) | 1,680.09 mi (2,703.85 km) |
| Ontario to Jonesboro (Arkansas) | 1,525.48 mi (2,455.03 km) |
| Ontario to Joplin (Missouri) | 1,312.19 mi (2,111.76 km) |
| Ontario to Joppatowne (Maryland) | 2,294.37 mi (3,692.44 km) |
| Ontario to Juana Díaz (Puerto Rico) | 3,321.46 mi (5,345.38 km) |
| Ontario to Junction City (Kansas) | 1,199.65 mi (1,930.65 km) |
| Ontario to Juneau (Alaska) | 1,851.79 mi (2,980.18 km) |
| Ontario to Jupiter (Florida) | 2,272.90 mi (3,657.87 km) |
| Ontario to Jupiter Farms (Florida) | 2,266.77 mi (3,648.01 km) |
| Ontario to Jurupa Valley (California) | 8.21 mi (13.22 km) |
| Ontario to Justice (Illinois) | 1,698.53 mi (2,733.52 km) |
| Ontario to Kahului (Hawaii) | 2,531.61 mi (4,074.23 km) |
| Ontario to Kailua (Hawaii) | 2,586.34 mi (4,162.31 km) |
| Ontario to Kalamazoo (Michigan) | 1,817.78 mi (2,925.44 km) |
