The line to Boussu was created by the state (as owner of the state railways and thus not resulting in competition) and was opened in 1899. It was owned and operated, not by the NMVB, but by the state. From the beginning the line was electrified. There was no connection with other tram lines in the Borinage because of difference in electricity. When the state railway NMBS was created in 1926, negotiations began to include the line in the network of the NMVB, which was carried out in 1928. A year later the line was extended in Boussu to the railway station of this place. A few years later direct trams began to ride from Mons to Dour (cap.67), when that line was electrified.

The Depot for the line was situated in Quaregnon

Operators:

• MB	From begin until 1928

• NMVB	From 1928 until end

Below a print of the timetable of the year 1931.