| Digitie Marketing | |
| Digitrillion | |
| DigiVie Communications, Inc. | Ontario |
| Digiwork Instruments | Ontario |
| Diguno | British Columbia |
| Dijitle | Alberta |
| Diligen | |
| Diligens, Inc. | Ontario |
| Diligent Communications, Inc. | Ontario |
| Dillon Consulting Ltd | Alberta |
| Dilypse | |
| Dimensional Business Solutions | Alberta |
| Dimensional Strategies, Inc. | Ontario |
| DineAmix, Inc. | Ontario |
| Dingo Games | British Columbia |
| Dingus & Zazzy | |
| Diobri | Quebec |
| Dion Gauthier, Inc. | |
| Dion Rodrigues | Ontario |
| Dionamix Scientific | |
| Dipmicro Electronics | Ontario |
| Dipôle Solutions | |
| Direct Access Radio Comm. | Ontario |
| Direct Data | Manitoba |
| Direct Impact Solutions | Quebec |
| Direct IT Corporation | Ontario |
| Direct Objective Consulting | Quebec |
| Direct Tec, Inc. | Alberta |
| Direct Updates | British Columbia |
| Direct Web Solutions | |
| DirectAdmin | Alberta |
| DirectDial.com | Ontario |
| Direction Informatique | Quebec |
| Directive Communication Systems, Inc. | |
| DirectNet | British Columbia |
| Directory Niagara | Ontario |
| Directory of Games | Ontario |
| Dirks Software | Ontario |
| Diros Technology, Inc. | |
| DIS Ltd | Ontario |
| Discerning Systems, Inc. | British Columbia |
| Disco | Ontario |
| Disco, Inc. | |
| Discover Coding | |
| Discover Media House, Inc. | |
| Discovery Centre | |
| Discovery Computers St. Albert AB | Alberta |
| Discovery Parks | British Columbia |
| Discovery Solutions International, Inc. | Alberta |
| Discoverygarden, Inc. | Prince Edward Island |