| Ontario to Security-Widefield (Colorado) | 786.44 mi (1,265.65 km) |
| Ontario to Sedalia (Missouri) | 1,389.21 mi (2,235.71 km) |
| Ontario to Sedro-Woolley (Washington) | 1,027.85 mi (1,654.17 km) |
| Ontario to Seguin (Texas) | 1,191.21 mi (1,917.07 km) |
| Ontario to Selden (New York) | 2,462.04 mi (3,962.27 km) |
| Ontario to Selma (Alabama) | 1,764.01 mi (2,838.90 km) |
| Ontario to Selma (California) | 208.38 mi (335.36 km) |
| Ontario to Selma (Texas) | 1,171.77 mi (1,885.78 km) |
| Ontario to Seminole (Florida) | 2,097.03 mi (3,374.85 km) |
| Ontario to Seven Hills (Ohio) | 2,012.96 mi (3,239.55 km) |
| Ontario to Seven Oaks (South Carolina) | 2,076.23 mi (3,341.36 km) |
| Ontario to Severn (Maryland) | 2,277.37 mi (3,665.08 km) |
| Ontario to Severna Park (Maryland) | 2,284.40 mi (3,676.39 km) |
| Ontario to Sevierville (Tennessee) | 1,921.90 mi (3,093.00 km) |
| Ontario to Seymour (Indiana) | 1,784.63 mi (2,872.09 km) |
