| ComputerSweden | Stockholm |
| Comsys AB | |
| Comtax AB | Skåne |
| Conapto | |
| Consafe Logistics AB | Skåne |
| Consenz | |
| Consid | |
| Consultera.Net | |
| Consupedia | |
| Contenta RAW Converter | Västerbotten |
| ContextVision AB | Stockholm |
| Cooach AB | |
| Cord Koncept | |
| Corelatus AB | Stockholm |
| Corline Biomedical AB | |
| Corona Software AB | Stockholm |
| Corpia | |
| CorPower Ocean | |
| Corsmed | |
| COS Systems AB | |
| Countagen AB | |
| Coupon Carrier AB | |
| Covr Security AB | |
| Crafoord Prize | |
| Creandum | Stockholm |
| Creative Brackets | |
| CredPoint Sweden AB | |
| Creed Media Group AB | |
| Cresponix | |
| Crisp | |
| CRM Treasury Systems | |
| Crobasoft Interactive | Stockholm |
| Crossbreed | |
| Crosser Technologies | |
| Crossnet AB | Stockholm |
| Crystone AB | Västmanland |
| CuraCell | |
| Curest AB | |
| Curity AB | |
| Curoflow | |
| Curovir AB | |
| Cursio AB | |
| Cybercom Group AB | Stockholm |
| Cybix AB | Uppsala |
| Cygate | Stockholm |
| Cygate AB | Värmland |
| Cykelbolaget Stockholm AB | |
| Cyxone AB | |
| Dagens industri | |
| Dalarna Digital | |