| South Portland to Sesena | 3,341.44 mi (5,377.53 km) |
| South Portland to Sestao | 3,275.98 mi (5,272.18 km) |
| South Portland to Sevilla | 3,325.41 mi (5,351.73 km) |
| South Portland to Sevilla La Nueva | 3,318.24 mi (5,340.19 km) |
| South Portland to Silla | 3,519.68 mi (5,664.37 km) |
| South Portland to Silleda | 3,052.26 mi (4,912.14 km) |
| South Portland to Sitges | 3,560.07 mi (5,729.38 km) |
| South Portland to Socuellamos | 3,410.03 mi (5,487.92 km) |
| South Portland to Soller | 3,650.44 mi (5,874.81 km) |
| South Portland to Solsona | 3,522.29 mi (5,668.58 km) |
| South Portland to Son Servera | 3,685.89 mi (5,931.86 km) |
| South Portland to Sonseca | 3,342.42 mi (5,379.11 km) |
| South Portland to Sopelana | 3,275.13 mi (5,270.81 km) |
| South Portland to Soria | 3,346.92 mi (5,386.35 km) |
| South Portland to Suances | 3,224.78 mi (5,189.78 km) |
