| OsOffice | Groningen |
| Osteo-Pharma B.V. | |
| Osudio | North Holland |
| OTB Ventures | |
| Otec Finance | South Holland |
| OTIV B.V. | |
| Otoconsult B.V. | |
| Otomi | |
| Otwee B.V. | North Holland |
| OTYS | Utrecht |
| Out of Site | North Brabant |
| OVAS Solutions B.V. | Flevoland |
| Overhoff Telecommunicatie B.V. | Gelderland |
| Override | Flevoland |
| Overstappen.nl B.V. | |
| Overstory | North Holland |
| OVSoftware B.V. | South Holland |
| Owlin | North Holland |
| Owlin B.V. | North Holland |
| OwnIT | Gelderland |
| Oxilion | Overijssel |
| OXO Ventures | |
| P-mex Webdesign | North Holland |
| Packaly B.V. | |
| Packard Bell | Gelderland |
| Pacmed | |
| PACT Care B.V. | |
| Pactechno | Utrecht |
| Pakweg.nl | Utrecht |
| Paladin Studios | South Holland |
| Paleo B.V. | |
| PamGene | North Brabant |
| Pan Cancer T | South Holland |
| Pangaea Digital Agency | South Holland |
| Panorama Laboratories | |
| Panoversal | Utrecht |
| Pantarhei Bioscience B.V. | |
| Pantheon Automatisering | Friesland |
| Pantheon B.V. | North Holland |
| Panthera B.V. | Utrecht |
| Pappenheimers | Gelderland |
| Papyrs | North Brabant |
| Paralax | Utrecht |
| Paramana | North Holland |
| Parc-Ink | South Holland |
| Parcom | |
| ParkBee B.V. | |
| Partners in Technology | Gelderland |
| Partout digital native agency | North Brabant |
| Parx Materials N.V. | |