It has expanded since its opening from 22 stations on two lines to 68 stations on four lines totalling 69.2 kilometres (43.0 mi) in length,[5][6] serving the north, east and centre of the Island of Montreal with connections to Longueuil, via the Yellow Line, and Laval, via the Orange Line.
The Montreal Metro is Canada's busiest rapid transit system in terms of daily ridership, delivering an average of 1,009,600 daily unlinked passenger trips per weekday as of the third quarter of 2024.[7] It is North America's third busiest rapid transit system, behind the New York City Subway and Mexico City Metro. In 2023, 303,969,500 trips on the Metro were completed.[7] With the Metro and the newer driverless, steel-wheeled Réseau express métropolitain, Montreal has one of North America's largest urban rapid transit systems, attracting the second-highest ridership per capita behind New York City.[8]