| National City to Smyrna (Delaware) | 2,343.53 mi (3,771.54 km) |
| National City to Smyrna (Georgia) | 1,876.26 mi (3,019.55 km) |
| National City to Smyrna (Tennessee) | 1,752.27 mi (2,820.00 km) |
| National City to Snellville (Georgia) | 1,905.55 mi (3,066.68 km) |
| National City to Snoqualmie (Washington) | 1,056.62 mi (1,700.46 km) |
| National City to Snyder (Texas) | 940.34 mi (1,513.33 km) |
| National City to Socastee (South Carolina) | 2,191.31 mi (3,526.56 km) |
| National City to Socorro (Texas) | 637.68 mi (1,026.24 km) |
| National City to Soddy-Daisy (Tennessee) | 1,830.37 mi (2,945.69 km) |
| National City to Solana Beach (California) | 24.53 mi (39.48 km) |
| National City to Soledad (California) | 355.53 mi (572.18 km) |
| National City to Solon (Ohio) | 2,040.97 mi (3,284.62 km) |
| National City to Somers Point (New Jersey) | 2,396.98 mi (3,857.57 km) |
| National City to Somerset (Kentucky) | 1,857.43 mi (2,989.24 km) |
| National City to Somerset (New Jersey) | 2,400.26 mi (3,862.84 km) |
