| South Portland to Greenwood (South Carolina) | 910.31 mi (1,465.00 km) |
| South Portland to Greenwood Village (Colorado) | 1,796.37 mi (2,890.98 km) |
| South Portland to Greer (South Carolina) | 875.27 mi (1,408.61 km) |
| South Portland to Grenada (Mississippi) | 1,248.60 mi (2,009.43 km) |
| South Portland to Gresham (Oregon) | 2,524.73 mi (4,063.16 km) |
| South Portland to Gretna (Louisiana) | 1,440.63 mi (2,318.47 km) |
| South Portland to Griffin (Georgia) | 1,040.44 mi (1,674.42 km) |
| South Portland to Griffith (Indiana) | 882.12 mi (1,419.63 km) |
| South Portland to Grimes (Iowa) | 1,197.96 mi (1,927.93 km) |
| South Portland to Grosse Pointe Park (Michigan) | 643.81 mi (1,036.11 km) |
| South Portland to Grosse Pointe Woods (Michigan) | 641.50 mi (1,032.40 km) |
| South Portland to Grove City (Ohio) | 707.35 mi (1,138.37 km) |
| South Portland to Groveland (Florida) | 1,218.59 mi (1,961.13 km) |
| South Portland to Grover Beach (California) | 2,708.81 mi (4,359.40 km) |
| South Portland to Groves (Texas) | 1,603.95 mi (2,581.31 km) |
