| Torben Bues Consulting & Services IT GmbH | |
| Torro-Softworks GmbH | Brandenburg |
| TOSHIBA Europe GmbH | North Rhine-Westphalia |
| Touch Art | Schleswig-Holstein |
| Tourbosoft GmbH | |
| Tourlane GmbH | |
| Touro University Berlin | |
| Tower Electronic Components GmbH | Baden-Württemberg |
| Toyota Deutschland GmbH | |
| Tozero GmbH | |
| tp-net OHG | North Rhine-Westphalia |
| TPS Data GmbH | Baden-Württemberg |
| TPWD AG | |
| TQ-Systems GmbH | Bavaria |
| TR Electronic GmbH | |
| tracdelight GmbH | |
| Traceless Materials GmbH | |
| TraceTronic GmbH | |
| Tracon Wismar Tradin & Consulting GmbH | Hesse |
| TRADE Software-Systeme GmbH | Baden-Württemberg |
| Tradegate AG | |
| TradersWorld GmbH | Baden-Württemberg |
| Tradewind | |
| Trading Company KG | Hesse |
| tradingtwins GmbH | |
| Tradinos | |
| Tradum GmbH | |
| Traffic Data Systems GmbH | |
| traffics Softwaresysteme für den Tourismus GmbH | Berlin |
| Traffitec GmbH | North Rhine-Westphalia |
| Traffix GmbH | Bavaria |
| Trafo2 GmbH | North Rhine-Westphalia |
| Tragant Handels- und Beteiligungs GmbH | Berlin |
| Train & Education | Berlin |
| Trajet GmbH | Lower Saxony |
| Trans-Logo-Tech (TLT) GmbH | |
| Transdata | North Rhine-Westphalia |
| Transfact GmbH | North Rhine-Westphalia |
| Transimmune AG | |
| Transinsight GmbH | Saxony |
| Transloadit-II GmbH | |
| Translumina GmbH | |
| Transporeon GmbH | |
| Transporter Lab GmbH | |
| TransWare AG | Rhineland-Palatinate |
| TrashMail.com | Baden-Württemberg |
| Travian Games GmbH | Bavaria |
| Travis CI | |
| Travis CI GmbH | Berlin |
| Trawa | |