| Chicago to Oak Harbor (Washington) | 1,746.25 mi (2,810.31 km) |
| Chicago to Oak Hills (Oregon) | 1,760.54 mi (2,833.32 km) |
| Chicago to Oak Lawn (Illinois) | 9.20 mi (14.80 km) |
| Chicago to Oak Park (California) | 1,761.58 mi (2,834.98 km) |
| Chicago to Oak Park (Illinois) | 6.33 mi (10.18 km) |
| Chicago to Oak Park (Michigan) | 234.73 mi (377.76 km) |
| Chicago to Oak Ridge (Florida) | 988.27 mi (1,590.47 km) |
| Chicago to Oak Ridge (New Jersey) | 684.80 mi (1,102.07 km) |
| Chicago to Oak Ridge (Tennessee) | 444.85 mi (715.91 km) |
| Chicago to Oakdale (California) | 1,771.39 mi (2,850.77 km) |
| Chicago to Oakdale (Minnesota) | 342.70 mi (551.53 km) |
| Chicago to Oakland (California) | 1,841.17 mi (2,963.08 km) |
| Chicago to Oakland (New Jersey) | 698.00 mi (1,123.32 km) |
| Chicago to Oakland Park (Florida) | 1,163.62 mi (1,872.66 km) |
| Chicago to Oakleaf Plantation (Florida) | 869.50 mi (1,399.33 km) |
