| Normal to Olympia Heights (Florida) | 1,136.90 mi (1,829.66 km) |
| Normal to Omaha (Nebraska) | 372.41 mi (599.34 km) |
| Normal to On Top of the World Designated Place (Florida) | 874.90 mi (1,408.01 km) |
| Normal to Onalaska (Wisconsin) | 258.83 mi (416.55 km) |
| Normal to Oneida (New York) | 707.89 mi (1,139.24 km) |
| Normal to Oneonta (New York) | 731.95 mi (1,177.96 km) |
| Normal to Ontario (California) | 1,627.74 mi (2,619.59 km) |
| Normal to Ontario (Oregon) | 1,444.01 mi (2,323.91 km) |
| Normal to Opa-locka (Florida) | 1,127.93 mi (1,815.23 km) |
| Normal to Opelika (Alabama) | 578.73 mi (931.38 km) |
| Normal to Opelousas (Louisiana) | 712.12 mi (1,146.04 km) |
| Normal to Orange (California) | 1,645.74 mi (2,648.56 km) |
| Normal to Orange (Texas) | 766.89 mi (1,234.19 km) |
| Normal to Orange City (Florida) | 911.28 mi (1,466.57 km) |
| Normal to Orangeburg (South Carolina) | 660.18 mi (1,062.46 km) |
