| Ontario to Maryland Heights (Missouri) | 1,537.51 mi (2,474.38 km) |
| Ontario to Marysville (California) | 416.36 mi (670.07 km) |
| Ontario to Marysville (Ohio) | 1,921.64 mi (3,092.58 km) |
| Ontario to Marysville (Washington) | 998.25 mi (1,606.52 km) |
| Ontario to Maryville (Missouri) | 1,320.56 mi (2,125.24 km) |
| Ontario to Maryville (Tennessee) | 1,900.07 mi (3,057.87 km) |
| Ontario to Mason (Ohio) | 1,870.20 mi (3,009.80 km) |
| Ontario to Mason City (Iowa) | 1,453.39 mi (2,339.00 km) |
| Ontario to Massapequa (New York) | 2,440.79 mi (3,928.08 km) |
| Ontario to Massapequa Park (New York) | 2,441.83 mi (3,929.75 km) |
| Ontario to Massillon (Ohio) | 2,019.10 mi (3,249.43 km) |
| Ontario to Mastic (New York) | 2,472.68 mi (3,979.40 km) |
| Ontario to Mastic Beach (New York) | 2,473.46 mi (3,980.65 km) |
| Ontario to Matteson (Illinois) | 1,700.65 mi (2,736.93 km) |
| Ontario to Matthews (North Carolina) | 2,088.19 mi (3,360.62 km) |
