| Company | Industry | City |
| Off Road Productions | Sudbury | |
| OmniG Software Inc. | Oakville | |
| Online-Learning.com | Ottawa | |
| Ontario Government, Cabinet Office | Toronto | |
| Onyx Consol | Oakville | |
| Operitel Corporation | Peterborough | |
| Organic | Toronto | |
| OTI Multimedia | Guelph | |
| Ovation Star Inc. | Toronto |