| Ottawa to Silver Firs (Washington) | 1,685.19 mi (2,712.04 km) |
| Ottawa to Silver Spring (Maryland) | 643.47 mi (1,035.57 km) |
| Ottawa to Silver Springs Shores (Florida) | 928.36 mi (1,494.04 km) |
| Ottawa to Silverdale (Washington) | 1,709.30 mi (2,750.85 km) |
| Ottawa to Silverton (Oregon) | 1,716.40 mi (2,762.28 km) |
| Ottawa to Simi Valley (California) | 1,695.64 mi (2,728.86 km) |
| Ottawa to Simpsonville (South Carolina) | 580.49 mi (934.20 km) |
| Ottawa to Sioux City (Iowa) | 396.59 mi (638.26 km) |
| Ottawa to Sioux Falls (South Dakota) | 430.13 mi (692.24 km) |
| Ottawa to Skokie (Illinois) | 73.15 mi (117.72 km) |
| Ottawa to Sleepy Hollow (New York) | 776.36 mi (1,249.43 km) |
| Ottawa to Slidell (Louisiana) | 766.50 mi (1,233.57 km) |
| Ottawa to Smithfield (North Carolina) | 695.19 mi (1,118.81 km) |
| Ottawa to Smithfield (Utah) | 1,185.37 mi (1,907.68 km) |
| Ottawa to Smithville (Missouri) | 331.53 mi (533.54 km) |
