Réseau express métropolitain (REM)

Alignment

The REM is an automated, electric light metro developed by CDPQ Infra. When complete it will have 67 km of line and 26 stations on four branches that meet downtown at Gare Centrale. Three branches are open. The South Shore branch (A1) runs from Brossard across the St. Lawrence on the Samuel De Champlain Bridge to Gare Centrale. The Deux-Montagnes branch (A4) runs through the century-old Mount Royal Tunnel and on through McGill, Édouard-Montpetit, and the northwest of the island to Deux-Montagnes on the North Shore. The Anse-à-l’Orme branch (A3) splits off at Bois-Franc and crosses the West Island through Des Sources, Fairview–Pointe-Claire, and Kirkland to Anse-à-l’Orme in Sainte-Anne-de-Bellevue.

The unfinished airport branch (A2) leaves the Anse-à-l’Orme line near Highway 13. It runs to Marie-Curie station in the Technoparc area, then through a 2.5 km tunnel to YUL-Aéroport-Montréal-Trudeau station at the airport. Track is installed along the whole branch. Aéroports de Montréal (ADM) is building the airport station, and the opening depends on that work.

Two infill stations on the South Shore branch are also in planning: Griffintown–Bernard-Landry, part of the original plan, on the north side of the Lachine Canal, and a station near Bridge and Wellington streets that the City of Montréal requested in 2023.

Updates

2026-10 — Airport branch testing reaches high speed

Trains on the airport branch now run in automatic mode at up to 100 km/h as far as Marie-Curie. The test zone will extend to the airport as ADM finishes the YUL station. The new branch will then be integrated into the operating network and given a dress rehearsal without passengers. Service is scheduled to start at the end of 2027, under the timetable agreed with ADM.

2026-06 — Planning starts for two infill stations

CDPQ Infra, the Government of Québec, and the City of Montréal began planning Griffintown–Bernard-Landry and a second station near Bridge and Wellington streets. The Canada Infrastructure Bank is adding C$250 million and Québec C$25 million; the final cost will come out of the planning work. CDPQ Infra recommends building both stations together, which it estimates will take about four years including planning, with construction possibly starting in 2028.

2026-05 — Anse-à-l’Orme branch opens

Four West Island stations opened on May 18, bringing the network to 23 stations, with about 35 minutes of travel from Anse-à-l’Orme to Gare Centrale. Radio-Canada reported about 78,000 riders a day and a recent single-day peak of 104,000, against a target of 150,000 a day for the full network. Trains were running on schedule 99.2% of the time.

2026-01 — First train runs on the airport branch

A train ran on the airport branch for the first time, beginning track and communication tests on the network’s last section. Track is in place for all 67 km, up to the tail track behind the airport station. The REM said dynamic testing must be complete by spring 2027, and that a 2027 opening depends on the airport station’s 2026 milestones being met.

2025-11 — Deux-Montagnes branch opens

Fourteen stations from McGill to Deux-Montagnes opened on November 17, 2025, linking the South Shore and North Shore by REM for the first time. More than 250,000 people visited the new stations during the free open-house weekend before service began.

2023-09 — Cost rises to C$7.95 billion

CDPQ Infra put the total cost at C$7.95 billion, up C$1.65 billion (26%) from 2018. It attributed about C$800 million to the pandemic and C$350 million to the Mount Royal Tunnel, where crews had found a century-old dynamite charge and a badly deteriorated central wall. Airport branch commissioning was set for 2027 to match the airport’s timetable for its station. The fact sheet now gives the total construction cost as C$8.34 billion.

2023-07 — South Shore branch opens

Service began on July 31, 2023, on the five-station line between Brossard and Gare Centrale, the first part of the REM to open. Construction had begun in spring 2018.