| Round Lake Beach to Mattoon (Illinois) | 201.02 mi (323.52 km) |
| Round Lake Beach to Mauldin (South Carolina) | 610.30 mi (982.18 km) |
| Round Lake Beach to Maumee (Ohio) | 233.67 mi (376.06 km) |
| Round Lake Beach to Maumelle (Arkansas) | 569.72 mi (916.88 km) |
| Round Lake Beach to Mayagüez (Puerto Rico) | 2,073.64 mi (3,337.20 km) |
| Round Lake Beach to Mayfield Heights (Ohio) | 345.65 mi (556.28 km) |
| Round Lake Beach to Mays Chapel (Maryland) | 629.96 mi (1,013.83 km) |
| Round Lake Beach to Maywood (California) | 1,723.96 mi (2,774.45 km) |
| Round Lake Beach to Maywood (Illinois) | 36.57 mi (58.86 km) |
| Round Lake Beach to McAlester (Oklahoma) | 660.81 mi (1,063.47 km) |
| Round Lake Beach to McAllen (Texas) | 1,255.68 mi (2,020.83 km) |
| Round Lake Beach to McCalla (Alabama) | 629.75 mi (1,013.48 km) |
| Round Lake Beach to McComb (Mississippi) | 780.53 mi (1,256.15 km) |
| Round Lake Beach to McDonough (Georgia) | 653.56 mi (1,051.80 km) |
| Round Lake Beach to McFarland (California) | 1,724.64 mi (2,775.53 km) |
