| Data Equipment | Oslo |
| Data Respons Norge AS | Akershus |
| Data.norge.no | Oslo |
| Databutton AS | |
| Datakvalitet | Troms |
| Datamatik AS | Oslo |
| Datatilsynet | |
| Deal.no | Oslo |
| Decisions AS | |
| Defero | |
| Defigo | |
| Deltager.no | |
| Desuvit | |
| Det Norske Videnskaps-Akademi | |
| Differ.Chat | Oslo |
| Digi.no | Oslo |
| Digimaker AS | Vest-Agder |
| DigiSpace AS | Vestfold |
| Digital Creations AS | Hordaland |
| Digital Impuls Oslo AS | Oslo |
| Digital Master | |
| Digitroll | Hordaland |
| DIGSTRA | |
| DIMEQ | |
| Dintero AS | |
| Direkte Data AS | Trøndelag |
| Disruptive Technologies | |
| Ditio AS | |
| DNB | |
| DNO ASA | |
| DNV | |
| Documaster AS | Oslo |
| Documents4j | |
| Dogu SalesScreen AS | |
| Dojob | |
| Dolphin ICS | Oslo |
| Dolphitech | |
| Domenia | Oslo |
| Domenshop | Oslo |
| DoMore Diagnostics AS | |
| Domos | |
| DroneMask | |
| Drupal Norge | Oslo |
| Dualog | |
| Dualog AS | Troms |
| Ducky | |
| Dune | |
| Dune | |
| Dynaspace | |
| Earth Science Analytics | |