| Yook GmbH | |
| YOOtheme GmbH | Hamburg |
| Yopeso GmbH | |
| You 2 Software | Bavaria |
| You Drive GmbH | |
| YouAtNotes GmbH | Hamburg |
| Youbility Software | Saxony |
| YouCard.de | Hesse |
| Youki GmbH | |
| youmex AG | |
| yoummday GmbH | |
| Young Digitals Consulting GmbH | |
| Young Leaders GmbH | |
| Youngcom GmbH | |
| Your Freedom | Rhineland-Palatinate |
| Your Server Admin | Saxony-Anhalt |
| yourdata GmbH | |
| Yours Truly GmbH | |
| YouTunez UG (haftungsbeschränkt) & Co. KG | |
| Ypsilon.Net AG | |
| Ysura GmbH | |
| Yttrium GmbH | |
| Yucca Technologies GmbH | |
| Yugen GmbH | |
| YUKKA Lab AG | |
| Yumab GmbH | |
| YUNIVERS GmbH | |
| Yunka | |
| Yunus Environment Hub | |
| Yunus Social Business | |
| Yupik - Marketing Public Relations GmbH | North Rhine-Westphalia |
| Yuri GmbH | |
| yWorks | Baden-Württemberg |
| Z-DBackup | Berlin |
| z-el GmbH | Bavaria |
| Z-LASER Optoelektronik GmbH | Baden-Württemberg |
| Z-Software GmbH | |
| z-weitsicht Fabian Sattler und Tobias Pfannschmidt GbR | Bremen |
| z3networks GmbH | Lower Saxony |
| za-internet GmbH | |
| ZaaK Technologies GmbH | |
| ZAB-Druck- & Webdesign | North Rhine-Westphalia |
| Zabel Technik GmbH | North Rhine-Westphalia |
| Zacharias GbR | North Rhine-Westphalia |
| Zahner Net GmbH | |
| Zammad GmbH | |
| Zana Technologies GmbH | Baden-Württemberg |
| Zander & Mielke GmbH | Hamburg |
| Zapf Systemhaus GmbH | Lower Saxony |
| ZAPware IT-Service eG | Baden-Württemberg |