| TiMe Networks IT-Systemhaus GbR | Bavaria |
| time:matters GmbH | |
| timeghost GmbH | |
| Timeless | |
| Timemaster | Lower Saxony |
| TimePanic | Bavaria |
| Timespin Digital Communication GmbH | Thuringia |
| Timesys AG | North Rhine-Westphalia |
| TIMETOACT Software & Consulting GmbH | North Rhine-Westphalia |
| TIMIFY | |
| Timing Software GmbH | |
| Timm Richter - Internet Consulting | Saarland |
| Timme Hosting GmbH & Co. KG | |
| timmersive UG (haftungsbeschränkt) | Berlin |
| Timo Nause tnwebconsulting | |
| TimO-Time Management Office GmbH | Hesse |
| Timon Paulsteiner IT- & Websolutions | |
| Tinloof | |
| Tintenklex Legasthenie Software | Schleswig-Holstein |
| Tintenmarkt | Rhineland-Palatinate |
| tintX-Shop | Thuringia |
| TinyWebGallery | Bavaria |
| TiProNet | Saxony |
| Tiptap | |
| TiPTO Internetagentur | North Rhine-Westphalia |
| TIQ Solutions GmbH | Saxony |
| Tiracon GbR | Saxony |
| Tirastel GmbH | |
| Tiron Service GmbH & Co. KG | North Rhine-Westphalia |
| TIS Consulting & Logistics GmbH | |
| TIS Technische Informationssysteme GmbH | North Rhine-Westphalia |
| TissUse GmbH | |
| Titan Networks Internet & Telecommunications Service Providing GmbH | |
| Tivola Publishing GmbH | Hamburg |
| TJ Labs | |
| Tk telefoncall GmbH | Baden-Württemberg |
| TK-Schulsoftware GmbH & Co. KG | |
| TK-Soft | Baden-Württemberg |
| TK-Vertrieb | Brandenburg |
| TKM Telekommunikation und Elektronik GmbH | North Rhine-Westphalia |
| TKR GmbH & Co. KG | Schleswig-Holstein |
| TL Electronic GmbH | Bavaria |
| tl;dv | |
| TLDR | |
| TLGG Agency GmbH | |
| TM-SOFT | Baden-Württemberg |
| tm-webentwicklung GmbH | North Rhine-Westphalia |
| TME Pharma AG | |
| TMI-Webdesign, Roeder & Dahl GbR | Brandenburg |
| TMKIS Internet Services | Hesse |