| South San Francisco to Oskaloosa (Iowa) | 1,599.99 mi (2,574.94 km) |
| South San Francisco to Oswego (Illinois) | 1,821.80 mi (2,931.91 km) |
| South San Francisco to Oswego (New York) | 2,412.60 mi (3,882.70 km) |
| South San Francisco to Otsego (Minnesota) | 1,571.22 mi (2,528.63 km) |
| South San Francisco to Ottawa (Illinois) | 1,797.64 mi (2,893.03 km) |
| South San Francisco to Ottawa (Kansas) | 1,472.05 mi (2,369.04 km) |
| South San Francisco to Ottumwa (Iowa) | 1,611.92 mi (2,594.14 km) |
| South San Francisco to Overland (Missouri) | 1,733.47 mi (2,789.74 km) |
| South San Francisco to Overland Park (Kansas) | 1,500.98 mi (2,415.59 km) |
| South San Francisco to Overlea (Maryland) | 2,457.64 mi (3,955.19 km) |
| South San Francisco to Oviedo (Florida) | 2,443.79 mi (3,932.91 km) |
| South San Francisco to Owasso (Oklahoma) | 1,465.85 mi (2,359.06 km) |
| South San Francisco to Owatonna (Minnesota) | 1,579.14 mi (2,541.37 km) |
| South San Francisco to Owensboro (Kentucky) | 1,918.11 mi (3,086.90 km) |
| South San Francisco to Owings Mills (Maryland) | 2,442.66 mi (3,931.08 km) |
