| Global Diagnostic Imaging, Healthcare IT & Radiation Therapy Trade Association | Brussels-Capital |
| Global Wind Energy Council | |
| GlobalTT | Walloon Brabant |
| Globule Bleu | Liège |
| Glucône S.P.R.L. | Brussels-Capital |
| Gorilla | |
| Govaerts N.V. | Antwerp |
| Grab IT | |
| Graphicomp N.V. | East Flanders |
| Greenomy S.R.L. | |
| Greenomy SRL | |
| GreenPulse | |
| GSP Partner | Walloon Brabant |
| Guardsquare N.V. | Flemish Brabant |
| H&H Informatique | |
| Hack Belgium Labs | |
| HALFIN S.A. | Brussels-Capital |
| Halos Websites | Antwerp |
| HandSoft Computer Solutions N.V. | |
| Handsom webdesign | East Flanders |
| Hanna Solutions | |
| Happy Volcano | |
| Harras Network C.V.B.A. | Antwerp |
| Hasselt University - Databases and Theoretical Computer Science Research Group | Limburg |
| Haute école Francisco Ferrer | |
| Haute École Léonard de Vinci | |
| Haute École Libre Mosane | |
| Hawkfield | East Flanders |
| Hebergeur.be | Hainaut |
| Heens | Brussels-Capital |
| Heens IT Consultancy | |
| Hello Customer | |
| HEMMIS N.V. | West Flanders |
| HERMES ECS S.A. | Walloon Brabant |
| Hestia IT | |
| Hex-Rays S.A./N.V. | Liège |
| HFInformatique S.P.R.L. | Liège |
| Hitechpc | Liège |
| Hogeschool VIVES | |
| Honeycomb | |
| Houff@-info S.P.R.L. | Luxembourg |
| House of HR | |
| House of Talents | |
| hsbcad | East Flanders |
| HSC Computers B.V. | Antwerp |
| HT-Solutions | |
| hub.brussels | |
| Humgy | |
| Hybrid Software | |
| Hyloris Pharmaceuticals S.A. | |