| EDP Web Design | Flemish Brabant |
| Edpnet | East Flanders |
| EDS Truck & Trailer Consulting | East Flanders |
| EDT Engineering | Hainaut |
| Edwin2Win S.P.R.L.U. | Hainaut |
| eeNews Europe | Walloon Brabant |
| Efficy S.A./N.V. | Brussels-Capital |
| Effitrax | |
| Effortel | |
| EIT Digital | Brussels-Capital |
| EIT Food | |
| Elia System Operator S.A./N.V. | Brussels-Capital |
| Elipse | Antwerp |
| Elium | Walloon Brabant |
| Ello Mobile | |
| Elmos | Antwerp |
| ELSI Solutions B.V.B.A. | |
| Elsyca N.V. | Flemish Brabant |
| Elyps S.A. | |
| Emakina Group | Brussels-Capital |
| Emmanuel Finkels | Walloon Brabant |
| Emweb | Flemish Brabant |
| Encima B.V. | Antwerp |
| Encon | |
| End-2-End S.P.R.L. | Liège |
| EnergyVision | |
| Enetricity B.V.B.A. | West Flanders |
| Enfocus | East Flanders |
| Entelec Control Systems B.V.B.A. | Limburg |
| EOS B.V. | |
| EpiGaN N.V. | Limburg |
| Epitopoietic Research Corporation | |
| epowerhr | Antwerp |
| Epson België | Flemish Brabant |
| ERTICO - ITS Europe | Brussels-Capital |
| ESC B.V. | East Flanders |
| Escent | Brussels-Capital |
| Esdaco | Antwerp |
| ESI Informatique | Liège |
| ET-Consulting | |
| Eteamsys | Liège |
| Ethera | Flemish Brabant |
| eTheRNA | |
| ETIS | Brussels-Capital |
| ETS Informatics | |
| Euregio.Net AG | Liège |
| EUREKA Secretariat AISBL | Brussels-Capital |
| Eureka Solutions | |
| Euresys S.A. | Liège |
| EURid | Brussels-Capital |