| Complea | North Jutland Region |
| ComplyCloud | |
| CompuSoft A/S | |
| Computer 112 | Capital Region of Denmark |
| Computer Huset ApS | |
| Computer Mester | Central Denmark Region |
| ComputerCamp A/S | |
| Computerworld A/S | Capital Region of Denmark |
| Computerworld it-jobban | |
| Computopic | Capital Region of Denmark |
| ComSystem A/S | |
| Concept Data A/S | Central Denmark Region |
| Conceptware | Capital Region of Denmark |
| Condes | Central Denmark Region |
| Conecto A/S | Capital Region of Denmark |
| Configit A/S | |
| Connect Media | |
| Conscensia | North Jutland Region |
| Conscia A/S | Capital Region of Denmark |
| Conscius | North Jutland Region |
| Contera Pharma A/S | |
| Contest A/S | Capital Region of Denmark |
| Contex A/S | Capital Region of Denmark |
| Contractbook | Capital Region of Denmark |
| Contractpedia ApS | |
| Convena Distribution A/S | Capital Region of Denmark |
| Conviator ApS | Region of Southern Denmark |
| Conzoom | |
| Cookie Information A/S | |
| Cookiebot | Capital Region of Denmark |
| Cooley Digital | |
| CopenData IVS | Capital Region of Denmark |
| Copenhagen Business School | |
| Copenhagen Fintech | |
| Copenhagen Infrastructure Partners P/S | |
| Copenhagen Rig | |
| Copenhagen Suborbitals | Capital Region of Denmark |
| Cordulus | |
| CoreSearch Vision A/S | |
| Cornator A/S | Central Denmark Region |
| Corti | |
| Cortrium | |
| CP Robotics | |
| CPH Cloud Company A/S | Capital Region of Denmark |
| Cphbusiness | |
| Creat it REAL ApS | North Jutland Region |
| Creative Oak ApS | |
| Crediwire ApS | |
| Criipto ApS | |
| Crown Tech | |