Bus services are provided throughout the Greater Montreal region of Canada under the Exo brand.^[1]

Prior to June 2017, bus service within the greater region of Montréal was provided by a number of different local and regional transit agencies known as Conseils Intermunicipal de Transport (CIT), or Inter-municipal transit commissions. In addition, a few suburban towns also ran their own transit services. All of these CITs and local agencies were, however, integrated logistically and collected fares under the umbrella of the former Agence métropolitaine de transport (AMT), a provincial agency created in 1997 to manage and integrate road transport and public transportation in Greater Montreal, as well as operate commuter rail for the region.

On June 1, 2017, the AMT was disbanded and replaced by two new entities, the Autorité régionale de transport métropolitain (ARTM), mandated to plan and integrate public transit and fares across the Greater Montreal region, and the Réseau de transport métropolitain (RTM), to organize and run the commuter train network and unite all public transport expertise of the former AMT with that of the CIT transit organizations in the northern and southern suburbs, including paratransit services.

The RTM took over service operation of over twelve former CITs and local transit agencies:^[2]

• AMT's own express bus lines
• CIT Haut-Saint-Laurent
• CIT La Presqu'Île
• CIT Laurentides
• CIT Le Richelain
• CIT Roussillon
• CIT Sorel-Varennes
• CIT Vallée du Richelieu
• CITSO (Sud-Ouest)
• RTCR de la MRC de L'Assomption^[3]
  • Urbis transport urbain des moulins^[4]
    • Keolis
  • Conseil Régional de transport de Lanaudière ^[5]
• Sainte-Julie public transit

Through its subsidiaries Exo runs multiple bus lines serving Montréal suburbs.

• Exo L'Assomption and Terrebonne - Mascouche sector
• Exo Laurentides sector

• Exo Chambly-Richelieu-Carignan sector
• Exo du Haut-Saint-Laurent sector
• Exo Le Richelain sector
• Exo Roussillon sector
• Exo Sainte-Julie sector
• Exo Sorel-Varennes sector
• Exo Sud-Ouest sector
• Exo de la Vallée du Richelieu sector
• Express Chevrier 90/Express Terminus Centre-Ville 90
  links Brossard-Chevrier Park and Ride to the Montreal
  Terminus Centre-Ville using Van Hool AG300 buses.
  It is run by the Réseau de transport de Longueuil
  which is not part of Exo.
• La Presqu'Île sector

• Autorité régionale de transport métropolitain
• Saint-Jean-sur-Richelieu public transit

• (in French) Réseau de transport métropolitain buses^{[permanent dead link]}
• (in English) Réseau de transport métropolitain buses (EN)