| CRIF Informatique | Isère |
| Crisalid S.A.S. | Moselle |
| Crisp IM S.A.R.L. | Loire-Atlantique |
| Cristal Concept S.A. | Haute-Savoie |
| Cristallin | Aube |
| CRM & DATA S.A.R.L. | Hauts-de-Seine |
| CRM360 | Nord |
| Croc pop up + | Loire-Atlantique |
| Croll | Paris |
| Crossject | |
| CrowdSec | |
| CRT Informatique | Maine-et-Loire |
| Crumble Création | Loire-Atlantique |
| Cruxpool | |
| Cryptio | |
| CryptoNext S.A.S. | |
| CryptPad | Paris |
| Cryptr | |
| CS Informatique | Mayenne |
| CS Programme | Haute-Savoie |
| Cs2i Bourgogne | Nièvre |
| CsetID | Haute-Savoie |
| CTIBiotech | |
| CTO Partners Group S.A.S. | |
| CTR Télécom | Isère |
| Cubde | Loire-Atlantique |
| Cube S.A.R.L. | Vendée |
| Cube43 | |
| Cubedesigners | Paris |
| Cubinfo | Haute-Saône |
| Cubyn | Paris |
| Cuers-Informatique | Gironde |
| Curadigm | |
| Curecall | |
| Curium Pharma | |
| Curseur | |
| CVasThera | Tarn |
| CVasThera | |
| CVFM Webmarketing | Paris |
| CVMH Solutions | Eure-et-Loir |
| CVprofessionnel | |
| CX Informatique | |
| CXR | Eure-et-Loir |
| CybelAngel | |
| Cyber07.com | Ardèche |
| Cyberbrain | Ille-et-Vilaine |
| CyberCité | Métropole de Lyon |
| CyberComm | Alpes-Maritimes |
| Cyberiance | Doubs |
| Cyberjobs | |