| Middlesex to McHenry (Illinois) | 723.68 mi (1,164.65 km) |
| Middlesex to McKeesport (Pennsylvania) | 281.30 mi (452.71 km) |
| Middlesex to McKinleyville (California) | 2,559.15 mi (4,118.56 km) |
| Middlesex to McKinney (Texas) | 1,321.95 mi (2,127.48 km) |
| Middlesex to McLean (Virginia) | 182.08 mi (293.03 km) |
| Middlesex to McMinnville (Oregon) | 2,447.76 mi (3,939.29 km) |
| Middlesex to McMinnville (Tennessee) | 699.14 mi (1,125.16 km) |
| Middlesex to McNair (Virginia) | 190.95 mi (307.31 km) |
| Middlesex to McPherson (Kansas) | 1,240.91 mi (1,997.06 km) |
| Middlesex to Mead Valley (California) | 2,376.16 mi (3,824.07 km) |
| Middlesex to Meadow Woods (Florida) | 928.27 mi (1,493.90 km) |
| Middlesex to Meadowbrook (Virginia) | 269.55 mi (433.80 km) |
| Middlesex to Meadville (Pennsylvania) | 303.05 mi (487.71 km) |
| Middlesex to Mebane (North Carolina) | 403.74 mi (649.76 km) |
| Middlesex to Mechanicsville (Virginia) | 254.77 mi (410.01 km) |
