| Abipa International | |
| Abivia Web Hosting | Ontario |
| ABK Biomedical, Inc. | Nova Scotia |
| ABKA Enterprises, Inc. | Alberta |
| Able Automation | Alberta |
| Able Innovations | |
| Able One | Ontario |
| AbleWebs | British Columbia |
| ABM Integrated Solutions | Ontario |
| ABnet | |
| Abora Web | Quebec |
| ABORG Computing, Inc. | Ontario |
| Aboriginal Computer Solutions Ltd | British Columbia |
| About Alberta Tech | |
| Above the Fold | |
| Above-The-Cloud.com | Ontario |
| ABRA Electronics Corporation | Quebec |
| Abrafo Négajoule | Quebec |
| ABS Information Systems, INc. | Ontario |
| ABS Point of Sale, Inc. | Ontario |
| Absolu | Quebec |
| Absolunet | Quebec |
| Absolute Computer Service, Inc. | Alberta |
| Absolute Computer Services | Saskatchewan |
| Absolute Computer Solutions Ltd | New Brunswick |
| Absolute Destruction | |
| Absolute Genius | Ontario |
| Absolute Imaging, Inc. | |
| Absolute Software Corporation | British Columbia |
| Absolute Toner Cartridge | Ontario |
| Absolutecreative | British Columbia |
| ABSOPULSE Electronics Ltd | Ontario |
| Abstract Fonts | |
| Abstractive Technology Consulting, Inc. | |
| ABWEB.ca | Alberta |
| AC Host Canada | Alberta |
| ACA Control Systems Ltd | Ontario |
| ACA Group of Companies | Ontario |
| ACA TMetrix, Inc. | Ontario |
| Académie de l'Entrepreneurship | |
| Académie Esports de Montréal | Quebec |
| Academos | |
| Academy of Applied Pharmaceutical Sciences | |
| Academy of Learning College PEI | |
| Acadia University | Nova Scotia |
| Acadia University - Acadia Institute for Data Analytics | Nova Scotia |
| Acadia University - Department of Mathematics & Statistics | Nova Scotia |
| Acadia University - Jodrey School of Computer Science | Nova Scotia |
| Acadian Computer Service | Ontario |
| Acadium, Inc. | Ontario |