| Wezy Design & Programming | Flemish Brabant |
| Whale | |
| Whitewater GCV | Antwerp |
| Whizu | Brussels-Capital |
| Wikiwi S.R.L. | Luxembourg |
| Willems Soft | Brussels-Capital |
| Wimi Games | East Flanders |
| Wims BIOS | Flemish Brabant |
| Win | Namur |
| Winamp | |
| WinAuditor S.P.R.L. | Walloon Brabant |
| Winbooks | Walloon Brabant |
| Winfakt | Antwerp |
| WinGames B.V.B.A. | Antwerp |
| WinGest | Flemish Brabant |
| Wings Software | Antwerp |
| Winking | West Flanders |
| WinPCWeb | Liège |
| Wireless Technology Labs | Flemish Brabant |
| Wisa B.V.B.A. | Flemish Brabant |
| Wisemen | |
| Wiver B.V.B.A. | Antwerp |
| WiverSoft | Antwerp |
| Wooclap | |
| Woodstone B.V.B.A. | Flemish Brabant |
| WooRank | Brussels-Capital |
| Workero | |
| WorldCall | Brussels-Capital |
| WS Computers | East Flanders |
| X-FAB Silicon Foundries SE | Limburg |
| X4C | |
| XatraX | East Flanders |
| XC Lab S.P.R.L. | Liège |
| Xcommerce | Flemish Brabant |
| Xdroid | |
| Xenics N.V. | Flemish Brabant |
| XenomatiX | |
| XEROX (Belgique) S.A. | Flemish Brabant |
| Xperthis | Brussels-Capital |
| Xplore N.V. | Flemish Brabant |
| Xpress Biologics | |
| XRintelligence S.R.L. | |
| XsolveIT | Limburg |
| Xtreme Internet Solutions B.V.B.A. | Limburg |
| Xylos | Antwerp |
| Xyzt.ai | |
| Yell-O-Snow | Brussels-Capital |
| Yellowshape | Antwerp |
| Yitch | |
| Your Mailing List Provider | West Flanders |