| XL Soft | Loire-Atlantique |
| XLEARN | |
| XLIM | Haute-Vienne |
| XLSTAT | Paris |
| XMCO | |
| XML C parser and toolkit of Gnome | Isère |
| XMLmind | Yvelines |
| Xmloperator | Hauts-de-Seine |
| Xname | Hauts-de-Seine |
| XnView | Marne |
| xo7 | |
| Xooit S.A.R.L. | Paris |
| XOOPS France | Loir-et-Cher |
| XPERTEAM | Hauts-de-Seine |
| XQual | Alpes-Maritimes |
| XR+ | |
| Xsalto | Isère |
| XSun | |
| XTR4L1F3 | |
| XtreemOS | Ille-et-Vilaine |
| XWiki | Paris |
| XXII Group | |
| Y SCHOOLS | |
| Y-Proximité | Paris |
| Yaal Coop | |
| Yacast | Paris |
| Yalty | |
| Yamgaille | Paris |
| Yann Esposito | |
| Yateo | Paris |
| Yatoo | Hérault |
| YaZiba.net | Indre-et-Loire |
| YBDesign | Alpes-de-Haute-Provence |
| YCE Partners | |
| Yeddir | |
| Yélé | |
| Yellowsys | |
| Yeman | Yvelines |
| YesGo | |
| Yesouiapp | Hérault |
| Yespark | |
| YesWeHack | Paris |
| YesWeHack S.A.S. | Paris |
| Yewth | |
| Yieldy | |
| Ylly | |
| YMAG | Côte-d'Or |
| Ymsoft | Alpes-Maritimes |
| Ynoveo | |
| Ynsect | |