The (REM, , ) is a light metro rapid transit system in Greater Montreal, Quebec, Canada. it consists of 23 stations spanning the of its A1, A3, and A4 branches, connecting Downtown Montreal with the suburb of Brossard and the northwestern Montreal suburbs. The A2 branch to the Montréal–Trudeau International Airport will open in 2027. A portion of the route was taken over from the Exo commuter rail Deux-Montagnes line and has been converted to light metro standards.
The driverless metro system is projected to cost . It is independent of, but connects to and complements, the existing Montreal Metro operated by the STM, as well as the Exo commuter rail. It is fully fare-integrated with ARTM's system. Trains on the network are fully automated and driverless, as well as equipped with air conditioning for summer operations. All stations on the network are heated, and the system's three underground stations are also air-conditioned. The network features platform screen doors at every station.
The line was built by CDPQ Infra, a subsidiary of the , an institutional investor that manages various public and para-public pension plans and insurance programs in Quebec. The first section of the REM between the Brossard on the South Shore and Central Station in Downtown Montreal opened on 31 July 2023. The system was formally inaugurated on 14 November 2025 in a ceremony attended by Prime Minister Mark Carney, Premier of Quebec François Legault and Mayor of Montreal Soraya Martinez Ferrada. The second section of the REM opened on 17 November 2025, extending the line north through the Mont Royal Tunnel and to the northwest to . The third section of the REM opened on 18 May 2026, extending the line west to .
History Background The Réseau express métropolitain has its origin in various railway projects, realized or not, which have succeeded each other in Montreal since the beginning of the 20th century.
Mount Royal Tunnel and Deux-Montagnes line In 1918, the Canadian Northern Railway (CNoR) completed construction of a tunnel under Mount Royal to allow its trains arriving from the north to reach downtown Montreal. Since ventilation in the tunnel was insufficient to use steam locomotives, the line through the tunnel was electrified from its opening. In the 1990s, the Agence Métropolitaine de Transport (AMT) took over operation of the Deux-Montagnes line from Canadian National, renovating it between 1993 and 1995 – with trains running through the tunnel to reach downtown Montreal.
When the Montreal Metro was developed in the 1960s, initial plans involved the Red Line that would use the Canadian National Railway (CN) tracks passing under Mount Royal to reach the northwest suburb of Cartierville from downtown Montreal. When Montreal was chosen to host Expo 67 in 1962, the Red Line was dropped – with the Yellow Line (Line 4) linking Montreal to the South Shore suburbs being built instead. The Red Line was still planned for construction as a "regional metro" line in the early 1980s."Le Métro fait surface: La ligne 6". Quebec Science, vol. 21, no. 3, Nov. 1982. Ministere des Transports du Quebec and le Conseil des Transports de la region de Montreal.
Train de l'Ouest Vaudreuil–Hudson, a commuter rail line serving the west of Montreal, shares its tracks with freight trains, thereby limiting the quantity and frequency of trains that can be run. From the 2000s onwards, municipalities in the west of the island pushed for improved commuter train service. The AMT proposed upgrades and improvements to the Vaudreuil–Hudson line, with the Aéroports de Montréal proposing an automated light metro (similar to the Canada Line in Vancouver) to serve the airport and the surrounding area.
South Shore From the 1970s onwards, proposals for improved public transport to connect the South Shore with downtown Montreal were made, often proposing the use of the Champlain Bridge, which opened in 1962. In the 1990s and 2000s, proposals were made for a light rail line that would use the Champlain Bridge ice control structure to cross the St. Lawrence River. In 2011, the Canadian government announced that a new bridge would be built to replace the existing Champlain Bridge, with two lanes reserved for public transit. In 2013, the Quebec government announced that it was proposing a new light rail line to cross the bridge. The new Champlain Bridge opened in 2019, with a separate deck reserved for the future rail corridor.
Announcement On 13 January 2015, Premier of Quebec Philippe Couillard and Michael Sabia, CEO of the Caisse de dépôt et placement du Québec (CDPQ), announced that the Crown corporation would define, build and finance major transportation projects in the province, with planned to be spent on infrastructure from 2014 to 2024. Two of these projects were the South Shore Line and the Train de l'Ouest toward the West Island, which eventually merged to become the core of the Réseau express métropolitain project.
On 22 April 2016, Sabia and Montreal mayor Denis Coderre unveiled the project, then known as the Réseau électrique métropolitain (REM) to the media. The estimated completion date for the first portion of the system was December 2020. On 22 June 2016, CDPQ Infra published two requests for qualification: one for the engineering, procurement, and construction contract and the other for the rolling stock, systems, operation, and maintenance. The estimated values of the two contracts were $4billion and $1.5billion, respectively.
On 25 November 2016, CDPQ Infra announced the addition of three new stations to the project. These new stations—Bassin Peel (which eventually became ), , and —would improve downtown Montreal service by integrating the REM with the Montreal Metro through connections to the Green and Blue Lines. Included with news of the three new stations was an increased price tag of $5.9billion for the entire project.
On 15 June 2017, the Government of Canada pledged $1.28billion to finance the project, completing the financing of the project. In February 2018, CDPQ Infra announced that the project had been renamed Réseau express métropolitain (REM), would cost $6.3 billion to build, and that the network would open gradually between 2021 and 2023 – starting with the South Shore.
Procurement On 28 June 2016, CDPQ Infra launched two public tenders in parallel: one for "Engineering, Procurement and Construction" (EPC, or "Ingénierie, Approvisionnement et Construction des infrastructures" (IAC) in French), and a second, for "Rolling Stock, Systems and Operation and Maintenance Services" (RSSOM, or "Fourniture du Matériel Roulant, de Systèmes de conduite automatique et de Services d'Exploitation et de Maintenance" (MRSEM) in French). The estimated values of the two contracts were $4billion and $1.5billion, respectively. Following a prequalification phase, the Caisse's subsidiary announced, on 10 November 2016, the qualified candidates that would be allowed to submit a bid: For the EPC contract, the competitors were: (1) the Groupe NouvLR consortium, composed of SNC-Lavalin Grands Projets, Dragados, Aecon, Pomerleau, EPC, and AECOM (2) the Kiewit-Eurovia consortium, formed by Kiewit Corporation, Eurovia, WSP Global, and Parsons Corporation; For the RSSOM contract, three companies and consortia were in competition: (1) Bombardier Transportation alone (2) Alliance Montréal Mobilité, composed of Parsons Corporation, Hyundai Rotem, RATP Dev, and Thales Canada (3) the Groupe des Partenaires pour la Mobilité des Montréalais, composed of Alstom and SNC-Lavalin O&M Ansaldo STS-Hitachi and China Railway International were not allowed to bid.
According to La Presse, final bids were submitted to CDPQ Infra on 27 October 2017. On 10 November 2017, the date of the planned announcement of the selected contractors, the procurement process was "postponed indefinitely" to provide more time for analysis and evaluation of the bids received. On 8 February 2018, CDPQ Infra finally announced its selection: the Groupe NouvLR consortium for the EPC contract (SNC-Lavalin Grands Projets, Dragados, Aecon, Pomerleau, EBC, and AECOM) and the Groupe des Partenaires pour la Mobilité des Montréalais for the RSSOM contract (Alstom and SNC-Lavalin O&M). As part of RSSOM contract, Alstom would deliver 212 Alstom Metropolis cars, forming 106 two-car trains. The contracts' total value was estimated to be around $6.3billion, of which approximately 80% was for the EPC contract. Groupe PMM rebranded as "Pulsar" in October 2025.
Construction Preparatory work began in late March 2018. On 12 April 2018, the project officially broke ground. In December 2019, CDPQ revised the capital cost of the project to $6.5billion, an increase of $230million. In February 2020, CDPQ confirmed the names of the 26 stations on the network.
In October 2020, the tunnel boring machine "Alice" (named after Canadian geologist Alice Wilson) started the tunnelling process to Montréal–Trudeau International Airport. In October 2020, the first completed train arrived in Montreal from India, where it had been manufactured.
In November 2020, a disruption from an "unexpected" explosion during the renovation of the Mount Royal Tunnel, likely caused by leftover century-old explosives, delayed the opening of the central section of the REM from 2022 to 2023.
In June 2021, CDPQ updated the project cost to $6.9billion, an increase of $350million, citing impacts from the COVID-19 pandemic in Montreal. In June 2022, CDPQ Infra acknowledged that construction issues with the Mount Royal Tunnel, labour shortages, and material supply issues would postpone the opening of most REM stations to 2024. The delay had also resulted in higher costs for the project overall, exceeding the previously projected budget of $6.9billion. No new estimate of the project cost was provided.
In November 2024, CDPQ announced that major construction work on the central section of the line had been completed, with testing to follow in 2025. An updated opening date of the fourth quarter of 2025 was announced. CDPQ also stated that the project cost had increased to – noting that they shouldered responsibility for cost overruns. Construction on the branch to Montréal–Trudeau International Airport continued, with an estimated opening date of the first quarter of 2027.
Operational history
The first five stations on the network, between Central Station and Brossard, opened for full service on 31 July 2023. An opening ceremony was held on 28 July 2023, with Prime Minister Justin Trudeau, Premier of Quebec François Legault, Mayor of Montreal Valérie Plante, president and CEO of CDPQ Charlies Emond, and president and CEO of CDPQ Infra Jean-Marc Arbaud inaugurating the line.
On the weekend of 29 and 30 July 2023, free service was available to the public. On the first day of public access, over 20,000 people rode the REM in the morning, prompting staff to turn away new riders.
Within the first three days of revenue operation, the new line suffered a number of service disruptions caused by stuck railway switches and computer issues. A spokesperson remarked that "there's always some adjustments to be made" with a new system on the scale of the REM.
the system had carried more than 1million passengers, with daily ridership of more than 30,000 for the month following its opening. In April 2024, CDPQ announced that weekday ridership had increased again, with "up to 36,000 daily riders". In September 2024, average weekday ridership had risen to 37,000 daily passengers, with Tuesdays being the busiest day (42,000 passengers). During an interview with Radio-Canada in February 2025, president and chief executive officer of CDPQ Infra Jean-Marc Arbaud stated ridership had increased to 45,000 on its busiest day.