| Zachary to Odenton (Maryland) | 1,002.86 mi (1,613.95 km) |
| Zachary to Odessa (Texas) | 665.33 mi (1,070.75 km) |
| Zachary to Ogden (Utah) | 1,368.18 mi (2,201.87 km) |
| Zachary to Oildale (California) | 1,641.44 mi (2,641.64 km) |
| Zachary to Ojus (Florida) | 743.63 mi (1,196.75 km) |
| Zachary to Okemos (Michigan) | 911.39 mi (1,466.74 km) |
| Zachary to Oklahoma City (Oklahoma) | 495.10 mi (796.78 km) |
| Zachary to Okmulgee (Oklahoma) | 441.96 mi (711.26 km) |
| Zachary to Olathe (Kansas) | 604.46 mi (972.78 km) |
| Zachary to Old Jamestown (Missouri) | 567.03 mi (912.55 km) |
| Zachary to Oldsmar (Florida) | 542.24 mi (872.66 km) |
| Zachary to Olean (New York) | 1,057.77 mi (1,702.31 km) |
| Zachary to Olive Branch (Mississippi) | 306.55 mi (493.34 km) |
| Zachary to Olivehurst (California) | 1,808.34 mi (2,910.25 km) |
| Zachary to Olney (Maryland) | 988.50 mi (1,590.84 km) |
