| Ontario to Silver Firs (Washington) | 983.68 mi (1,583.09 km) |
| Ontario to Silver Spring (Maryland) | 2,260.64 mi (3,638.15 km) |
| Ontario to Silver Springs Shores (Florida) | 2,111.79 mi (3,398.59 km) |
| Ontario to Silverdale (Washington) | 977.64 mi (1,573.35 km) |
| Ontario to Silverton (Oregon) | 805.71 mi (1,296.66 km) |
| Ontario to Simi Valley (California) | 67.19 mi (108.13 km) |
| Ontario to Simpsonville (South Carolina) | 2,005.74 mi (3,227.93 km) |
| Ontario to Sioux City (Iowa) | 1,285.79 mi (2,069.29 km) |
| Ontario to Sioux Falls (South Dakota) | 1,296.43 mi (2,086.41 km) |
| Ontario to Skokie (Illinois) | 1,706.34 mi (2,746.09 km) |
| Ontario to Sleepy Hollow (New York) | 2,418.18 mi (3,891.68 km) |
| Ontario to Slidell (Louisiana) | 1,642.71 mi (2,643.69 km) |
| Ontario to Smithfield (North Carolina) | 2,215.50 mi (3,565.50 km) |
| Ontario to Smithfield (Utah) | 623.58 mi (1,003.56 km) |
| Ontario to Smithville (Missouri) | 1,323.99 mi (2,130.76 km) |
