Luxembourg
total: 274 km
standard gauge: 274 km 1.435-m gauge (242 km electrified) (2004)

Macedonia
total: 699 km
standard gauge: 699 km 1.435-m gauge (233 km electrified) (2004)

Madagascar
total: 732 km
narrow gauge: 732 km 1.000-m gauge (2004)

Malawi
total: 797 km
narrow gauge: 797 km 1.067-m gauge (2004)

Malaysia
total: 1,890 km (207 km electrified)
standard gauge: 57 km 1.435-m gauge (57 km electrified)
narrow gauge: 1,833 km 1.000-m gauge (150 km electrified) (2004)

Mali
total: 729 km
narrow gauge: 729 km 1.000-m gauge (2004)

Man, Isle of
total: 61 km (35 km electrified) (2003)

Mauritania
717 km
standard gauge: 717 km 1.435-m gauge (2004)

Mexico
total: 17,634 km
standard gauge: 17,634 km 1.435-m gauge (2004)

Moldova
total: 1,138 km
broad gauge: 1,124 km 1.520-m gauge
standard gauge: 14 km 1.435-m gauge (2004)