| OneVisage S.A. | |
| Oniko AG | Aargau |
| Onlime GmbH | Zurich |
| Online Consulting AG | St. Gallen |
| Online Marketing AG | Zug |
| Online PC | Zurich |
| OnlineDoctor AG | |
| OnSpirix Ltd | Zug |
| OOIT.com AG | Zurich |
| Opacc Software AG | Lucerne |
| Open Net S.à.r.l. | Vaud |
| Open Systems AG | Zurich |
| Openconcept AG | Bern |
| Opendata.ch | |
| OpenLimit SignCubes AG | Zug |
| Openline GmbH | Basel-Stadt |
| Oper | |
| Opna Bio S.A. | |
| Optimanet Schweiz AG | Zurich |
| Optimatik AG | Appenzell Ausserrhoden |
| Optimex IT-Services | Lucerne |
| Optimiso Group S.A. | Geneva |
| Optimo Medical AG | |
| Option-Web.ch | Valais |
| Optiprint AG | St. Gallen |
| Optive AG | Thurgau |
| OQTACORE S.à.r.l. | |
| ORamaVR S.A. | |
| Orbitare AG | |
| Orc Webhosting | Zurich |
| ORCA Systems | Zurich |
| OrdiCom S.A. | Vaud |
| Oriented.net | Basel-Stadt |
| OriginStamp AG | |
| Ortic Solutions | Obwalden |
| Osa Informatica S.A. | Ticino |
| Ostschweizer Fachhochschule | |
| Ovomind.com | |
| OWN Vernetzer GmbH | Valais |
| Oxegena S.à.r.l. | Vaud |
| P&P Software GmbH | Thurgau |
| Pabio | Bern |
| Pablo Niklas & Fils S.A. | Vaud |
| Pädagogische Hochschule Schaffhausen | Schaffhausen |
| Pädagogische Hochschule Zürich | Zurich |
| Padrone | Zug |
| PageFormance | Zurich |
| PageUp AG | Bern |
| Pallon Ltd | |
| pan-x | Zurich |