| Timag Group Ltd | Plovdiv |
| Tixi | Sofia |
| ToIvEl Ltd | Sofia |
| TokWise | |
| Toner.BG | Sofia |
| Tonerdirect | Sofia |
| Topvine Consulting OOD | |
| Topweb | Sofia |
| TORIN Company Ltd | Sofia |
| Tradeon.bg | |
| Transmetrics | Sofia |
| Trierra Soft | Plovdiv |
| Trixir | Sofia |
| Truesight Technologies | |
| TSD Group Ltd | |
| Tumba Solutions | Sofia |
| TVM Engineering Services Ltd | |
| Tweerous OOD | Sofia |
| Ubitrack | Sofia |
| UltraNet | Sofia |
| UltraPlay | Sofia |
| UltraServer | Plovdiv |
| UMD-Studio | Plovdiv |
| Umni Ltd | Sofia |
| Unacs | Sofia |
| Unax | |
| Underline | Varna |
| Unicom Services Ltd | Sofia |
| Unicoms | Varna |
| Unicontsoft | Sofia |
| Unisis Ltd | Sofia |
| Unisoftware | Sofia |
| United Partners | Sofia |
| University of Economics - Varna | Varna |
| University of Food Technologies in Plovdiv | Plovdiv |
| University of Library Studies and Information Technologies | Sofia |
| University of National and World Economy | Sofia |
| University of Sofia "St. Kliment Ohridski" - Faculty of Mathematics and Informatics | Sofia |
| University of Sofia - Department of Information Technologies | Sofia |
| University of Telecommunications and Posts | Sofia |
| University of Veliko Tarnovo | Veliko Tarnovo |
| UnrealSoft Ltd | Sofia |
| Update.bg | |
| Upnetix | Sofia |
| UXP | Sofia |
| Valbo Net | Sofia |
| Valentin Petroff | Sofia |
| Vali Computers | Sofia |
| VanboDevelops | |
| Vario | Sofia |