| Houston to Sestu | 5,635.54 mi (9,069.53 km) |
| Houston to Settimo Torinese | 5,369.74 mi (8,641.76 km) |
| Houston to Seveso | 5,409.14 mi (8,705.18 km) |
| Houston to Sezze | 5,728.66 mi (9,219.38 km) |
| Houston to Siano | 5,825.74 mi (9,375.63 km) |
| Houston to Siena | 5,585.69 mi (8,989.30 km) |
| Houston to Signa | 5,558.64 mi (8,945.76 km) |
| Houston to Silea | 5,538.24 mi (8,912.94 km) |
| Houston to Silvi Paese | 5,732.43 mi (9,225.46 km) |
| Houston to Sinalunga | 5,606.49 mi (9,022.78 km) |
| Houston to Siniscola | 5,616.12 mi (9,038.28 km) |
| Houston to Sinnai | 5,640.48 mi (9,077.47 km) |
| Houston to Siracusa | 6,000.83 mi (9,657.41 km) |
| Houston to Solaro | 5,407.93 mi (8,703.23 km) |
| Houston to Soliera | 5,516.03 mi (8,877.19 km) |
