| Connect 2 Communications GmbH | Lucerne |
| Connect-i S.à.r.l. | Vaud |
| Connect44 | Lucerne |
| Connectcom Networks S.A. | Vaud |
| Conrad Electronic S.A. | Schwyz |
| Conrad Engineering | Aargau |
| Conseils et Développements Informatiques S.A. | Fribourg |
| Consensus Informatik AG | Basel-Landschaft |
| conseo | |
| Consultinform AG | Zurich |
| Container Registry | |
| Contao | |
| Contaxe AG | Schaffhausen |
| Contech Electronic AG | Zurich |
| Contentserv Swiss GmbH | |
| Contovista AG | |
| Contreforme S.à.r.l. | Neuchâtel |
| Contrinex AG | Fribourg |
| Coople | |
| COP Informatik AG | St. Gallen |
| Coppelia Robotics AG | |
| Copper | |
| Copresence AG | |
| CORE Association | Geneva |
| Coresystems AG | Aargau |
| CorFlow | |
| Corintis | |
| Corintis | |
| Corix AG | Solothurn |
| Cosapien GmbH | |
| Cotecna | |
| Couniq Consulting AG | Bern |
| Coworking Bottighofen | |
| Coworking Frauenfeld GmbH | |
| Coworking Lounge Tessinerplatz | |
| Coworking Switzerland | |
| CPAutomation S.A. | Fribourg |
| Cradle Switzerland AG | |
| Creaholic S.A. | |
| Creaitor AI | |
| CREAL S.A. | |
| CREAL3D S.A. | Vaud |
| Crealogix AG | |
| Creanet Internet Services AG | Lucerne |
| Créateur de Site | Vaud |
| Creative Acts GmbH | Basel-Stadt |
| Creative Web Studio GmbH | Lucerne |
| CreativeSpace AG | |
| Credema AG | |
| Credit Suisse Group AG | |