| Zachary to Oskaloosa (Iowa) | 738.91 mi (1,189.16 km) |
| Zachary to Oswego (Illinois) | 777.36 mi (1,251.04 km) |
| Zachary to Oswego (New York) | 1,193.97 mi (1,921.52 km) |
| Zachary to Otsego (Minnesota) | 1,017.58 mi (1,637.64 km) |
| Zachary to Ottawa (Illinois) | 750.07 mi (1,207.11 km) |
| Zachary to Ottawa (Kansas) | 595.59 mi (958.51 km) |
| Zachary to Ottumwa (Iowa) | 718.90 mi (1,156.95 km) |
| Zachary to Overland (Missouri) | 556.80 mi (896.09 km) |
| Zachary to Overland Park (Kansas) | 602.16 mi (969.08 km) |
| Zachary to Overlea (Maryland) | 1,021.62 mi (1,644.14 km) |
| Zachary to Oviedo (Florida) | 614.56 mi (989.04 km) |
| Zachary to Owasso (Oklahoma) | 472.43 mi (760.30 km) |
| Zachary to Owatonna (Minnesota) | 934.54 mi (1,504.00 km) |
| Zachary to Owensboro (Kentucky) | 541.73 mi (871.83 km) |
| Zachary to Owings Mills (Maryland) | 1,010.94 mi (1,626.95 km) |
