| CodeCreator ApS | |
| CodeDroids | Region of Southern Denmark |
| Codesealer ApS | |
| Cofero Cables A/S | Capital Region of Denmark |
| Cogo ApS | |
| Coherence ApS | |
| Coinify | |
| Colibo | |
| CollecTech ApS | |
| Collectia A/S | |
| Columbus | Capital Region of Denmark |
| Comadan A/S | Central Denmark Region |
| Comapping.com | Region Zealand |
| CoMaSys ApS | Region of Southern Denmark |
| COMAsystem ApS | |
| ComboTope Therapeutics ApS | |
| Comcores ApS | |
| COMM2IG | Capital Region of Denmark |
| 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 |
| Cookie Information A/S | |
| Cookiebot | Capital Region of Denmark |
| Cooley Digital | |
| Coop Bank | Capital Region of Denmark |
| CopenData IVS | Capital Region of Denmark |