| Dotline Web, Inc. | |
| dotmobile | |
| Dotnoc dot com | British Columbia |
| Dots & Coms | Ontario |
| Dotscape | |
| Dotster | British Columbia |
| Dott Brown, Inc. | Ontario |
| Double "T" Computer Services | Saskatchewan |
| Double Digit Designs | Ontario |
| Double Stalion Games | Quebec |
| Double-echo Creation, Inc. | Quebec |
| Doucet Technologies | |
| Dougan Consulting Group | British Columbia |
| Douglas College | British Columbia |
| Douglas College - Computing Science | British Columbia |
| Douglas Information Systems Corporation | |
| Douglas Marketing Group | Ontario |
| Dovico | New Brunswick |
| Dovico Software, Inc. | |
| DOWCO Consultants Ltd | British Columbia |
| Dowdel, Inc. | |
| Downtown Computer Centre | British Columbia |
| Downtown Digital | Nova Scotia |
| Downtown.AI | British Columbia |
| Doxa Design | Quebec |
| DoxCity | Ontario |
| Doxim | |
| DPA Communications Corporation | Ontario |
| DPD Software Ltd | Manitoba |
| DPG Associates | British Columbia |
| DPG Communication | |
| DPI Digital People, Inc. | British Columbia |
| DPL Wireless | New Brunswick |
| DPT Security | Prince Edward Island |
| Dpt. | Quebec |
| Dr Ordi PC Dr | New Brunswick |
| Dr Robot, Inc. | Ontario |
| DR Systems, Inc. | |
| DR Technologies Ltd | Alberta |
| DR-Unlimited | Ontario |
| Dr. Computer Logick | Ontario |
| Dr. Craig S. Bruce | New Brunswick |
| Dr. David Kumka | British Columbia |
| Dr. Geek | Alberta |
| Dr. Phone Fix | |
| Dr. Stephen Makonin | British Columbia |
| Dr.Bill | |
| Dracal | |
| Draft | |
| Drafter.com | Quebec |