The organization was created by the Government of Quebec on June 1, 2017, replacing the former planning mandate of the Agence métropolitaine de transport (AMT).

Attempts at planning, coordinating, operating and integrating regional public transit in the Greater Montreal area have been made since 1970, with the mandates from different levels of government, including: Bureau de transport métropolitain (BTM), accountable to the Montreal Urban Community; Bureau d'aménagement du réseau express métropolitain (BAREM, unrelated to the current REM); Conseil des transports de la région de Montréal (COTREM), manated by the Quebec Ministry of Transportation (MTQ), the Conseil métropolitain de transport en commun (CMTC), created by an Act of the National Assembly and; Divisions of the MTQ itself.

[8] On June 1, 2017, Bill 76 was implemented: the AMT was officially dissolved and replaced by two newly created organizations: the ARTM and the Réseau de transport métropolitain (RTM).

The AMT's planning mandate went to the ARTM, while the operation of the various commuter rail lines across the Greater Montreal became the responsibility of the RTM (later rebranded Exo).

[20] In July 2023, the ARTM unveiled its updated metropolitan transit network map, in time for the inauguration of the first branch of the REM.

In addition, the agency also organizes carpooling, offering unloading spaces near public transit services in several of its park-and-ride lots, which allow for transfers to the bus, Metro or commuter train.