| ACDEV Software | Ontario |
| ACDL Computers, Inc. | Ontario |
| ACE Networks & Computer Systems, Inc. | Ontario |
| ACE POS Solutions Ltd | Ontario |
| Ace SEO Consultant | Alberta |
| Ace Technology, Inc. | Quebec |
| Ace Web Services | |
| Acela-Services | |
| Acentury, Inc. | |
| Aceon Data Recovery | British Columbia |
| AceProject | Quebec |
| Acerta Analytics Solutions, Inc. | |
| Acesoft | |
| ACET | Quebec |
| ACET Quantum | |
| Acetech Leadership | |
| AceTools.net | Ontario |
| Acetronic Industrial Controls, Inc. | Ontario |
| AChen Enterprises, Inc. | Ontario |
| Achieve IT | |
| Achieve Online | Alberta |
| Achievers Corporation | Ontario |
| Achiga | Ontario |
| Achilles Software | British Columbia |
| ACIAGA, Inc. | |
| Acies AI Ltd | |
| ACIS Consulting | Ontario |
| ACLAB | |
| ACM Automation, Inc. | Alberta |
| ACM Symposium on Document Engineering | Nova Scotia |
| ACME Communication, Inc. | Quebec |
| Acme Telephone Company | Ontario |
| Acme Works | |
| ACO Services | Ontario |
| Acolyte | |
| Acolyte communication | Quebec |
| Acolyte Technologies | Ontario |
| Acomba | Quebec |
| Acorn | |
| Acorn Biolabs, Inc. | |
| Acorn Interactive, Inc. | |
| ACORN Nova Scotia | |
| ACP Communications Technologies, Inc. | Ontario |
| ACP Computer Accessories | British Columbia |
| Acquaintance Media | |
| Acquired Notions | Ontario |
| Acquisio | Quebec |
| Acquizition.biz | |
| ACR Computers | Ontario |
| Acre Security | |