The Société de transport de Montréal or Montreal Transit Corporation operates transit services in Montreal. It is the 4th heaviest used system in North America after New York City, Mexico City and Toronto.

Type: Public

Fleet Size: 1,845 Low Floor buses

Routes: 220 Regular Service Routes, 23 Night Bus Routes

Manufacturer and Powerplant: STM sources its entire fleet from NovaBus which is also based in Quebec. Its fleet is powered by Diesel and Biodiesel engine powerplants.

Fare Collection: The Contactless Card Payment System in Montreal is called OPUS Card. OPUS Card replaced the older magnetic contact fare cards previously used prior to 2008. It is used almost all transit agencies in the Province of Quebec. Unique in that it can hold and identify 3 different types of fares such as day, month and weekly passes it was delayed two years due to various complications.

Livery: STM uses upbeat themes of blue and yellow which combine in some areas to make green set on a white unpainted backdrop. STM does frequently sell the sides and exterior of its buses for advertising space.

Innovations: STM as an entity is relatively young being founded only in 2002. The previous organization was founded in 1861 as the first railways in Montreal. STM was founded to replace the older organization. Formerly STM provided regional transport for the entire region, STM does still however connect to other public systems throughout the area.