| ASG Canada | Montréal | Information Technologies (IT) |
| Ashley's Little Gift Shop | Lachine | Candles |
| ASI Computer Technologies (Canada) Corp | Montréal | Information Technologies (IT) |
| Asplundh Canada | Terrebonne | Life Sciences and Health Technologies (LSHT) |
| Assima Canada / Wizart Canada | Montréal | Information Technologies (IT) |
| Association des scouts du Canada | Villeray | Tout Arts et divertissement, Tout Communautés et société |
| Association des Techniciens en Sant... | Lachine | Tout Entreprises et services |
| Association Sociale Inca Canada | Montréal | Associations |
| Assurance123.ca | Lachine | Tout Entreprises et services |
| ASSYSTEM PRODUCT ENGINEERING CANADA | Montréal | Aerospace |
Publicité (Desktop) Publicité (Mobile) |
| AstraZeneca Canada | Longueuil | Life Sciences and Health Technologies (LSHT) |
| AT&T Canada | Centre-Ville | Tout Entreprises et services |
| ATCO Distributions | Laval | Compressors |
| ATD DESIGN SERVICES (4071468 CANADA INC.) | Sainte-Geneviève | Aerospace |
| Atek Canada | Montréal | Tout Informatique et internet |
| Atelier De Daria Centro Canada | Montréal | Furniture Stores |
| ATEM Canada Inc | Montréal | Information Technologies (IT) |
| AtGen Canada | Laval | Life Sciences and Health Technologies (LSHT) |
| Atlas Copco Compressors Canada | Dollard Des Ormeaux | Life Sciences and Health Technologies (LSHT), Compressors |
| Aurora Importation & Distribution I... | Anjou | Tout Entreprises et services |
Publicité (Desktop) Publicité (Mobile) |
| Aurora Importation et distribution | Montréal | Agri-food |
| Aust & Hachmann (Canada) Ltd | Pointe-Claire | Agri-food |
| Auticonsult Canada | Étage | Information Technologies (IT) |
| Auto Camping | Lachine | Auto Part Manufacturers & Wholesalers |
| Auto Diesel 119483 Canada Inc | Laval | Auto Part Manufacturers & Wholesalers |
| Auto Hall Canada | Montréal | Car Repair |
| Auto Hall Canada Pie IX Inc | Montréal | Automobiles, car Dealers |
| Auto Kool | Lachine | Auto Part Manufacturers & Wholesalers |
| Auto Laser Canada | Montréal | Automobiles, car Dealers |
| Auto Rental Canada | Montréal | Auto Services |
Publicité (Desktop) Publicité (Mobile) |
| Auto Shaltas Garage Inc | Lachine | Auto Body Shop |
| Autobus Montroyal Inc | Lachine | Chauffeur Services |
| Automat Technologies | Montréal | Information Technologies (IT) |
| Automaticash | Lachine | Automated Teller Manufacturers & Wholesalers |
| Automic Canada Logiciels | Montréal | Information Technologies (IT) |
| Automont Distributions Inc | Longueuil | Auto Part Manufacturers & Wholesalers |
| Autos Internationales Lachine | Lachine | Tout Commerces au détail |
| Avaya Canada Corp | Montréal | Information Technologies (IT) |
| Avenant SST Inc | Lachine | Health Services |
| Avery Dennison Fasson Canada Inc. | Vaudreuil-Dorion | Tout Entreprises et services |
Publicité (Desktop) Publicité (Mobile) |
| Avery Weigh-Tronix Canada | Pointe-Claire | Tout Entreprises et services |
| AVI-SPL Canada Ltd | Montréal | Information Technologies (IT) |
| AVIALL CANADA LIMITED | Boisbriand | Aerospace |
| Aviall Canada Ltd | Boisbriand | Aircraft Parts, Engines & Avionics |
| Avison Young Canada | Centre-Ville | Tout Entreprises et services |
| Aviva Canada | Montréal | Car Insurance |
| Avnet Canada Inc. | Montréal | Tout Entreprises et services |
| Avnet International (Canada) Ltd | Montréal | Information Technologies (IT) |
| Avon Canada Inc. | Pointe-Claire | Tout Commerces au détail |
| Azelis canada | Boucherville | Chemicals |
