| BiologIC Technologies Ltd | |
| Biomathematics and Statistics Scotland | |
| BioMed Central Ltd | |
| Biometrics Ltd | Newport |
| Biomodal | |
| BioMoti | |
| Bionical Emas | |
| Bioniq | |
| BioPartner UK | |
| Biopharm Services Ltd | |
| Biopharma Group | |
| Biopharma Process Systems Ltd | |
| BioPharmaSpec Ltd | |
| Biorelate Ltd | |
| BIOS Health Ltd | |
| Biosceptre International Ltd | |
| Biosynth Ltd | |
| Biotangents Ltd | |
| Biotechflow | |
| Biotecnol Ltd | |
| Biotherapy Services Ltd | |
| BioToolomics | |
| BipTap | |
| Birak IT | |
| Birch Hosting Ltd | Staffordshire |
| Bird & Bird, LLP | |
| Bird Marketing Ltd | |
| Birdie Care Services Ltd | |
| Biringham Research Park | |
| Birkbeck, University of London | Greater London |
| Birkbeck, University of London - Department of Computer Science and Information Systems | Greater London |
| Birkbeck, University of London - Department of Economics, Mathematics and Statistics | Greater London |
| Birmingham City University | West Midlands |
| Birmingham Computer Repair | |
| Birmingham Data Recovery | West Midlands |
| Birmingham Newman University | |
| Birmingham Ormiston Academy | West Midlands |
| Birmingham PC Repair | |
| Birmingham Tech | |
| Bismuth Digital Solutions Ltd | West Midlands |
| Bison Grid Ltd | |
| Bisplex | |
| Bistech plc | |
| Bit Wave Solutions Ltd | Berkshire |
| bit.bio | |
| BitBazar | |
| Bitbot Studios | |
| BitBox Ltd | Hampshire |
| BitChute | |
| bitConcat Ltd | |