| Ontario to Arcata (California) | 589.62 mi (948.90 km) |
| Ontario to Archdale (North Carolina) | 2,122.24 mi (3,415.41 km) |
| Ontario to Arden-Arcade (California) | 378.87 mi (609.73 km) |
| Ontario to Ardmore (Oklahoma) | 1,169.61 mi (1,882.31 km) |
| Ontario to Ardmore (Pennsylvania) | 2,347.81 mi (3,778.44 km) |
| Ontario to Arecibo (Puerto Rico) | 3,294.54 mi (5,302.04 km) |
| Ontario to Arkadelphia (Arkansas) | 1,400.54 mi (2,253.96 km) |
| Ontario to Arkansas City (Kansas) | 1,172.56 mi (1,887.05 km) |
| Ontario to Arlington (Tennessee) | 1,585.01 mi (2,550.82 km) |
| Ontario to Arlington (Texas) | 1,183.47 mi (1,904.61 km) |
| Ontario to Arlington (Virginia) | 2,256.96 mi (3,632.22 km) |
| Ontario to Arlington (Washington) | 1,004.05 mi (1,615.86 km) |
| Ontario to Arlington Heights (Illinois) | 1,694.71 mi (2,727.38 km) |
| Ontario to Arnold (Maryland) | 2,288.44 mi (3,682.89 km) |
| Ontario to Arnold (Missouri) | 1,541.83 mi (2,481.33 km) |
