| Bloomsbury Institute London | |
| Bloomstar | Devon |
| Bloss Ltd | |
| Blot Design | Edinburgh |
| Blott.io Ltd | |
| BLS Computers | |
| Blu Frame | |
| Blu Wireless | |
| Blubolt Ltd | Somerset |
| Bludelta Ltd | Greater Manchester |
| Blue Box IT | South Yorkshire |
| Blue Chilli Microsystems Ltd | Kent |
| Blue Chip | Bedfordshire |
| Blue Chip Bridge Ltd | East Sussex |
| Blue Chip Technology Ltd | Cheshire |
| Blue Digital | |
| Blue Earth Diagnostics | |
| Blue Earth Therapeutics Ltd | |
| Blue Electronics Design Solutions Ltd | Swansea |
| Blue Fin Software Solutions | Newry, Mourne and Down |
| Blue Flag Technologies | West Sussex |
| Blue Frontier | Wiltshire |
| Blue Fusion Web | |
| Blue Lake Venture Capital | |
| Blue Lobster IT Ltd | Isle of Anglesey County Council |
| Blue Monkee | |
| Blue Monkey Web | Cambridgeshire |
| Blue Parrot Software Ltd | Channel Islands |
| Blue Pecan Computer Training | |
| Blue Penguins UK Telecom Ltd | Greater Manchester |
| Blue Prism Ltd | |
| Blue Reliance Ltd | |
| Blue Rock Digital | |
| Blue Rock Systems | Hampshire |
| Blue Shark | Tyne and Wear |
| Blue Skies Space | |
| Blue Sky Education | Surrey |
| Blue Sky Hosting Ltd | Greater London |
| Blue Sky Systems | |
| Blue Solutions Ltd | Berkshire |
| Blue Spark Ltd | Kent |
| Blue Sparrow | |
| Blue Square Management | |
| Blue Sword | Glasgow |
| Blue Tahiti Software Ltd | Bristol |
| Blue Water Web Ltd | |
| Blue Whale Media Ltd | |
| Blue Wren Ltd | |
| Blue Yonder Research | |
| Blue-i Event Technology | |