| Sveon България | Sofia |
| Svetlin Nakov | Sofia |
| Swipe.bg | Sofia |
| Synergyc | Sofia |
| Sysco Set Electronics Ltd | Sofia |
| Systech Ltd | Sofia |
| Take.bg | Sofia |
| Tangra Technology Group Ltd | Sofia |
| tbi bank | Sofia |
| TBI Info | Sofia |
| TBS Ltd | Sofia |
| Team Vision | Sofia |
| Tech Talks | Sofia |
| Tech4Kids | Sofia |
| TechNews.bg | Sofia |
| Technical University of Gabrovo | Gabrovo |
| Technofy Ltd | Sofia |
| TechnoLogica | |
| Technology 4 Business | Sofia |
| Technology School Electronic Systems | Sofia |
| TechnoMarket | Sofia |
| Technopolis | Sofia |
| Technopro | Sofia |
| TechWork | Sofia |
| Telecom Service Bulgaria | Sofia |
| Telecoms | Sofia |
| Telelink | |
| Telelink Bulgaria EAD | Sofia |
| Telelink Business Services | Sofia |
| Telenor | Sofia |
| Telerik | Sofia |
| Telerik Academy | |
| Telnet.bg | Sofia |
| Tendrik | Plovdiv |
| TETRACOM Interactive Solutions Ltd | Sofia |
| Texim Bank | Sofia |
| The Business Institute | |
| The Mags | Sofia |
| The Recursive | Sofia |
| ThinkWeb | Sofia |
| Tickey | Sofia |
| Tiger Technology | Sofia |
| Timag Group Ltd | Plovdiv |
| Tixi | Sofia |
| ToIvEl Ltd | Sofia |
| Toner.BG | Sofia |
| Tonerdirect | Sofia |
| Topweb | Sofia |
| TORIN Company Ltd | Sofia |
| Transmetrics | Sofia |