| Name | Region |
|---|---|
| Big Screen Ltd | Norfolk |
| Big Society Capital | |
| Big Surf Digital | Glasgow |
| Big Toe Web Design | |
| Big Toner UK | West Midlands |
| Big Wet Fish | Mid and East Antrim |
| BigBlast Design | Hertfordshire |
| BigChange | |
| Bigespas Ltd | |
| Bigfoot Digital Ltd | |
| Bigfork Ltd | Norfolk |
| Bigg Ltd | Bristol |
| Bigger Picture | Hampshire |
| BigHand | |
| BigHat Digital Ltd | |
| BigLemon | |
| Bignames | Glasgow |
| BigSoft Ltd | Berkshire |
| Bigupdata | |
| Bilderlings Pay Ltd | |
| Billdu Ltd | |
| Billian IT Solutions | Lancashire |
| Billsby | |
| BIM.Technologies | |
| Bimotech Solutions Ltd | |
| Binary Charm Ltd | |
| Binary Delights | Lisburn and Castlereagh |
| Binary Forge Solutions | |
| Binary Integration | Devon |
| Binary Reality | Greater Manchester |
| Binary Systems | |
| Binary Technologies Ltd | Glasgow |
| Binary-Studio | |
| BinaryWebs | |
| Bindoff Media | West Yorkshire |
| Bio-AMD | |
| Bio-Diagnostics Ltd | |
| Bioapp Solutions | |
| BioAscent | |
| BioBeats | |
| BioCaptiva Ltd | |
| Biocentris | |
| Biochromex | |
| Biocomposites | |
| BioCorteX Ltd | |
| Biodexa Pharmaceuticals plc | |
| Biofortuna Ltd | |
| Bioinduction Ltd | |
| Bioinformatics Organization | Greater Manchester |
| Bioinsights Publishing Ltd |