| Llanelli to Silver Firs (Washington) | 4,646.88 mi (7,478.44 km) |
| Llanelli to Silver Spring (Maryland) | 3,490.60 mi (5,617.57 km) |
| Llanelli to Silver Springs Shores (Florida) | 4,165.14 mi (6,703.14 km) |
| Llanelli to Silverdale (Washington) | 4,672.51 mi (7,519.68 km) |
| Llanelli to Silverton (Oregon) | 4,824.57 mi (7,764.39 km) |
| Llanelli to Simi Valley (California) | 5,305.43 mi (8,538.26 km) |
| Llanelli to Simpsonville (South Carolina) | 3,902.97 mi (6,281.22 km) |
| Llanelli to Sioux City (Iowa) | 4,089.30 mi (6,581.10 km) |
| Llanelli to Sioux Falls (South Dakota) | 4,051.97 mi (6,521.01 km) |
| Llanelli to Skokie (Illinois) | 3,784.13 mi (6,089.97 km) |
| Llanelli to Sleepy Hollow (New York) | 3,270.32 mi (5,263.08 km) |
| Llanelli to Slidell (Louisiana) | 4,429.73 mi (7,128.96 km) |
| Llanelli to Smithfield (North Carolina) | 3,704.01 mi (5,961.03 km) |
| Llanelli to Smithfield (Utah) | 4,661.78 mi (7,502.41 km) |
| Llanelli to Smithville (Missouri) | 4,170.77 mi (6,712.21 km) |
