| Chemaxon Ltd | |
| ChemPass Ltd | |
| Chipland Számítástechnikai Kft. | Borsod-Abaúj-Zemplén |
| Ciaran Foley | Budapest |
| CIB Bank | Budapest |
| Clarity Consulting Kft. | Budapest |
| Cleware Informatika Kft. | Pest |
| Cloud Labs Kft. | |
| Cloudstorm | |
| Cobra Computer Kft. | Budapest |
| CodeBerry School Kft. | |
| Codebuild Kft. | |
| CodeCluster | |
| CodeCluster | |
| CodeLinks Kft. | |
| CodersRank Ltd | |
| CodeVision | |
| CodeYard Kft. | |
| Colabs Startup Center Zrt. | Budapest |
| Com5 Kft. | Budapest |
| Combit Számítástechnikai Zrt. | Budapest |
| Comet Kft. | |
| ComParts Line Kft. | Budapest |
| Compete Digital | Budapest |
| Compocity | |
| Component Soft | |
| Component Soft Kft. | Budapest |
| Compure Kft. | Budapest |
| Computer Emporium | |
| Computer Imperium Kft. | Budapest |
| Computerworld.hu | Budapest |
| CompuTREND Zrt. | |
| Compuworx Informatikai Zrt. | Budapest |
| Comtech | |
| Conet Számítógép és Hálózatfejlesztő Kft. | Budapest |
| ConfigCat | |
| ConorFund | |
| Consulting Hungary | |
| Control X-Medical Ltd | |
| CONTROLLTraining Kft. | Budapest |
| Cordines Computer Kft. | Budapest |
| Cosmo Consult Kft. | Budapest |
| CoWo Budapest | |
| Craftbot | |
| cre-art stúdió | Zala |
| Creatic Online Kft. | |
| Creative Accelerator | |
| Crome Communication Kft. | |
| CrySyS Lab | |
| CSB IT Hosting & Consulting Bt. | |