| Delta Source | Antwerp |
| DeltaBlue Cloud Platform | |
| DentAdmin | East Flanders |
| DentaSoft | |
| Design Express | Antwerp |
| Despec Solutions B.V.B.A. | East Flanders |
| DESTIN-Informatique | Walloon Brabant |
| Destiny | Flemish Brabant |
| Destiny N.V. | East Flanders |
| DeuterOncology N.V. | |
| DevAtWork | Brussels-Capital |
| Develop-it | |
| Devolder | East Flanders |
| Devoxx Belgium | West Flanders |
| DevTech S.P.R.L. | Liège |
| Dgenious | |
| Diagenode | |
| Diamond Software | Antwerp |
| Digi-work | Brussels-Capital |
| Digibel | Limburg |
| Digicious | Brussels-Capital |
| Digicor B.V.B.A./S.P.R.L. | Flemish Brabant |
| Digimedia.be | Brussels-Capital |
| DigiNet N.V. | Flemish Brabant |
| Digipolis Antwerpen | |
| Digita B.V. | Brussels-Capital |
| Digital Attraxion | |
| Digital Impulse | Walloon Brabant |
| Digital Ninja B.V.B.A. | |
| Digital Printing Company B.V. | |
| Digital Wallonia | |
| DIGITALEUROPE | Brussels-Capital |
| DigitalMarketing.Brussels | Brussels-Capital |
| DigitalMind B.V. | |
| Digiteal S.A. | |
| Digitec Solution | Walloon Brabant |
| Digiti | |
| DigitOffice | |
| Digitown Webdesign Gent | West Flanders |
| DigiVision | |
| Digon | Antwerp |
| Dime Software | |
| Dinec International S.A. | Walloon Brabant |
| Diogenius | Walloon Brabant |
| Diomedia | West Flanders |
| Dionamic | Antwerp |
| DISA | Brussels-Capital |
| Discai | |
| Diskldee | Brussels-Capital |
| DMNET-APFF A.S.B.L. | Brussels-Capital |