| Company | Industry | City |
| A Train Media Inc. | Toronto | |
| A51 Integrated | Toronto | |
| Achilles Media | Professional Services | Toronto |
| ACTRA | Toronto | |
| ACTRA | Toronto | |
| Ad Lounge | Toronto | |
| Adeo Communications Corporation | Toronto | |
| Advanced Recruitment Consultants Inc. | Toronto | |
| Adverdea Inc. | Burlington | |
| Aesthetec | Social, Cultural and Arts | Toronto |
| Affinity Productions | Ottawa | |
| Affirmative Communications Inc. | Burlington | |
| Affirmative Insight Inc. | Woodbridge | |
| AirTime Media | Toronto | |
| AJE Productions Inc. | Toronto | |
| Algoma Games for Health | Sault Ste. Marie | |
| Algoma University College | Schools and Training | Sault Ste. Marie |
| AlignMark | Markham | |
| Alliance Atlantis Communications | Toronto | |
| Alliance for Children and Television (ACT) | ||
| ALT Software Inc. | Toronto | |
| Ambit Perspectives | Toronto | |
| Amiware Inc. | Aurora | |
| Analogue | Ottawa | |
| Andrew Tolomizenko Law Offices | Toronto | |
| Antradar Software | Thornhill | |
| Aporia Records Inc | Toronto | |
| Apption Software | Ottawa | |
| Aquent Creative & Marketing Staffing | Toronto | |
| Arcadia Production | Montreal | |
| Archives & Museum Informatics | Toronto | |
| Armantus | Toronto | |
| Armstrong Partnership Ltd. | Toronto | |
| Arnica Software Corporation | Toronto | |
| Artech Studios | Ottawa | |
| Artez Interactive | Toronto | |
| Association of Universities and Colleges of Canada | Ottawa | |
| Ast Networks | Toronto | |
| Astral Media | Toronto | |
| ATI Technologies Inc. | Markham |