| Chicago to Oakley (California) | 1,809.70 mi (2,912.44 km) |
| Chicago to Oakton (Virginia) | 582.98 mi (938.22 km) |
| Chicago to Oakville (Missouri) | 272.35 mi (438.31 km) |
| Chicago to Oatfield (Oregon) | 1,749.27 mi (2,815.18 km) |
| Chicago to Ocala (Florida) | 927.89 mi (1,493.30 km) |
| Chicago to Ocean Acres (New Jersey) | 715.27 mi (1,151.11 km) |
| Chicago to Ocean City (New Jersey) | 708.69 mi (1,140.52 km) |
| Chicago to Ocean Pines (Maryland) | 703.35 mi (1,131.93 km) |
| Chicago to Ocean Pointe (Hawaii) | 4,254.72 mi (6,847.31 km) |
| Chicago to Ocean Springs (Mississippi) | 792.05 mi (1,274.68 km) |
| Chicago to Oceanside (California) | 1,718.30 mi (2,765.34 km) |
| Chicago to Oceanside (New York) | 733.93 mi (1,181.14 km) |
| Chicago to Ocoee (Florida) | 978.98 mi (1,575.52 km) |
| Chicago to Oconomowoc (Wisconsin) | 96.44 mi (155.21 km) |
| Chicago to Odenton (Maryland) | 608.33 mi (979.02 km) |
