| Williamsport to Siloam Springs (Arkansas) | 1,003.60 mi (1,615.13 km) |
| Williamsport to Silver Firs (Washington) | 2,234.67 mi (3,596.36 km) |
| Williamsport to Silver Spring (Maryland) | 154.57 mi (248.76 km) |
| Williamsport to Silver Springs Shores (Florida) | 883.39 mi (1,421.68 km) |
| Williamsport to Silverdale (Washington) | 2,260.63 mi (3,638.14 km) |
| Williamsport to Silverton (Oregon) | 2,290.71 mi (3,686.54 km) |
| Williamsport to Simi Valley (California) | 2,306.14 mi (3,711.38 km) |
| Williamsport to Simpsonville (South Carolina) | 531.91 mi (856.03 km) |
| Williamsport to Sioux City (Iowa) | 997.36 mi (1,605.10 km) |
| Williamsport to Sioux Falls (South Dakota) | 1,015.02 mi (1,633.51 km) |
| Williamsport to Skokie (Illinois) | 555.04 mi (893.25 km) |
| Williamsport to Sleepy Hollow (New York) | 164.91 mi (265.40 km) |
| Williamsport to Slidell (Louisiana) | 1,038.48 mi (1,671.28 km) |
| Williamsport to Smithfield (North Carolina) | 401.99 mi (646.94 km) |
| Williamsport to Smithfield (Utah) | 1,787.30 mi (2,876.39 km) |
