| South Portland to Johnstown (Pennsylvania) | 498.27 mi (801.89 km) |
| South Portland to Joliet (Illinois) | 918.53 mi (1,478.23 km) |
| South Portland to Jonesboro (Arkansas) | 1,206.02 mi (1,940.90 km) |
| South Portland to Joplin (Missouri) | 1,347.07 mi (2,167.89 km) |
| South Portland to Joppatowne (Maryland) | 427.64 mi (688.22 km) |
| South Portland to Juana Díaz (Puerto Rico) | 1,780.97 mi (2,866.19 km) |
| South Portland to Junction City (Kansas) | 1,407.83 mi (2,265.68 km) |
| South Portland to Juneau (Alaska) | 2,832.70 mi (4,558.78 km) |
| South Portland to Jupiter (Florida) | 1,278.45 mi (2,057.47 km) |
| South Portland to Jupiter Farms (Florida) | 1,280.87 mi (2,061.36 km) |
| South Portland to Jurupa Valley (California) | 2,588.73 mi (4,166.15 km) |
| South Portland to Justice (Illinois) | 898.74 mi (1,446.38 km) |
| South Portland to Kahului (Hawaii) | 5,049.50 mi (8,126.38 km) |
| South Portland to Kailua (Hawaii) | 5,088.07 mi (8,188.46 km) |
| South Portland to Kalamazoo (Michigan) | 778.19 mi (1,252.37 km) |
