| Owings Mills to Odenton (Maryland) | 24.43 mi (39.31 km) |
| Owings Mills to Odessa (Texas) | 1,519.89 mi (2,446.03 km) |
| Owings Mills to Ogden (Utah) | 1,844.71 mi (2,968.78 km) |
| Owings Mills to Oildale (California) | 2,312.94 mi (3,722.32 km) |
| Owings Mills to Ojus (Florida) | 949.88 mi (1,528.68 km) |
| Owings Mills to Okemos (Michigan) | 457.45 mi (736.19 km) |
| Owings Mills to Oklahoma City (Oklahoma) | 1,166.18 mi (1,876.78 km) |
| Owings Mills to Okmulgee (Oklahoma) | 1,083.03 mi (1,742.96 km) |
| Owings Mills to Olathe (Kansas) | 965.12 mi (1,553.22 km) |
| Owings Mills to Old Jamestown (Missouri) | 723.65 mi (1,164.61 km) |
| Owings Mills to Oldsmar (Florida) | 854.03 mi (1,374.42 km) |
| Owings Mills to Olean (New York) | 203.51 mi (327.51 km) |
| Owings Mills to Olive Branch (Mississippi) | 780.69 mi (1,256.40 km) |
| Owings Mills to Olivehurst (California) | 2,370.22 mi (3,814.49 km) |
| Owings Mills to Olney (Maryland) | 23.66 mi (38.08 km) |
