| Ontario to Anoka (Minnesota) | 1,493.46 mi (2,403.49 km) |
| Ontario to Ansonia (Connecticut) | 2,459.00 mi (3,957.38 km) |
| Ontario to Antelope (California) | 384.62 mi (618.99 km) |
| Ontario to Anthem (Arizona) | 314.86 mi (506.72 km) |
| Ontario to Antioch (California) | 358.96 mi (577.69 km) |
| Ontario to Antioch (Illinois) | 1,694.66 mi (2,727.30 km) |
| Ontario to Apache Junction (Arizona) | 351.67 mi (565.95 km) |
| Ontario to Apex (North Carolina) | 2,184.16 mi (3,515.06 km) |
| Ontario to Apollo Beach (Florida) | 2,120.97 mi (3,413.38 km) |
| Ontario to Apopka (Florida) | 2,148.62 mi (3,457.86 km) |
| Ontario to Apple Valley (California) | 41.03 mi (66.04 km) |
| Ontario to Apple Valley (Minnesota) | 1,490.01 mi (2,397.94 km) |
| Ontario to Appleton (Wisconsin) | 1,705.78 mi (2,745.18 km) |
| Ontario to Arbutus (Maryland) | 2,277.04 mi (3,664.54 km) |
| Ontario to Arcadia (California) | 25.51 mi (41.06 km) |
