| WiFi.PRO | Málaga |
| WifiRed, S.L. | Almería |
| Wifisafe Spain, S.L. | Barcelona |
| Wild Wild Web Digital, S.L. | Madrid |
| Windar Renovables, S.A.U. | |
| Windtechnics | |
| Winhotel Solutions | Balearic Islands |
| WinOmega.com | Barcelona |
| WinPYME | Asturias |
| Winworld | Barcelona |
| Wireless Galicia | Pontevedra |
| Wireless Mundi, S.L. | Madrid |
| Wirum Tech | Madrid |
| Wise Athena | Madrid |
| Wiserentr Digital, S.L. | Madrid |
| WITRAC | Valencia |
| Wiyo | Madrid |
| Woffu Job Organizer, S.L. | Barcelona |
| Woffu Job Organizer, S.L. | Barcelona |
| Woinemer Technology, S.L. | Madrid |
| Wolters Kluwer España, S.A. | Madrid |
| WonderBits | Valencia |
| Woom | Barcelona |
| Woonivers | Madrid |
| Wooptix, S.L. | Madrid |
| Worksible, S.L. | Valencia |
| World Wide Mobility | Madrid |
| Worldcoo | |
| Worldsensing | Barcelona |
| Wsoko | Barcelona |
| Wulia | Barcelona |
| Wurth, S.L. | A Coruña |
| wwwarcelona | Barcelona |
| Wyred Web | Madrid |
| WYSIWYG | Barcelona |
| X.25 Informática | Madrid |
| X1Wind | Barcelona |
| Xacom Comunicaciones, S.L. | Madrid |
| Xailer | Madrid |
| XaolServer | Valencia |
| Xarxa Consultoria Informàtica, S.L. | Barcelona |
| Xarxa Control, S.L. | Girona |
| Xatcom | Barcelona |
| Xatinet Solucions Informàtiques, S.L. | Valencia |
| Xave World | Barcelona |
| XenonFactory | Zamora |
| Xepient Solutions | Murcia |
| Xeridia | León |
| Xerintel Internet Technologies, S.L. | Cádiz |
| Xicons Studio | Barcelona |