| Buzz Financial Services Ltd | Basildon | 2020 |
| Buzz IT Services Limited | Bury St. Edmunds | 2025 |
| Buzz Shop Ltd | London | 2024 |
| Buzzacott Audit Services Limited | London | 2022 |
| Buzzcut INK Ltd | Hayes | 2025 |
| Buzzit International Ltd | London | 2019 |
| BV Ltd | Newmarket | 2009 |
| BV Trade Ltd | Truro | 2019 |
| Bvapes Ltd | Stoke-On-Trent | 2024 |
| BVB Black Velvet Boutique Ltd | Oldham | 2025 |
| BVG Ltd | West Sussex | 2023 |
| Bvgmav Ltd | Cambridge | 2019 |
| BVM Moto Limited | Stroud | 2014 |
| BVM Skipton Limited | Harrogate | 2010 |
| BVR Tech Ltd | Isleworth | 2019 |
| Bvrefoot Limited | Sevenoaks | 2025 |
| BVS Store Limited | Coventry | 2019 |
| BW Legal Services Scotland Limited | Glasgow | 2016 |
| BW Ltd | Newmarket | 2022 |
| Bwaraat Group Ltd | Wellingborough | 2021 |
| Bwfc Limited | Warrington | 2019 |
| Bwgy Investments Limited | Bathgate | 2015 |
| BWH Alliance Limited | Selby | 2021 |
| BWK Sport Limited | Hailsham | 2015 |
| BWL (Racing) Invest Limited | High Wycombe | 1983 |
| BWM Business Solutions Limited | Wellingborough | 2019 |
| BWP Consulting Ltd | Maidstone | 2007 |
| BWP Technical Services Limited | Halesowen | 1988 |
| Bwrl Ltd | London | 2024 |
| BWS Office Furniture Limited | Blackpool | 2013 |
| BXI6 Limited | Derby | 2012 |
| Bxmex Limited | Cambridge | 2020 |
| BY Alexandra Aesthetics Ltd | Liverpool | 2023 |
| BY Belovd Ltd | Potters Bar | 2023 |
| BY CHI Limited | London | 2023 |
| BY Choice Estate Agents Limited | Sudbury | 2007 |
| BY Education (Peterborough Schools) Holdings Limited | London | 2006 |
| BY Jamie Ltd | London | 2024 |
| BY Martin Limited | Mildenhall | 2024 |
| BY My Properties Limited | Ilford | 2007 |
| BY Naomi Ltd | London | 2021 |
| BY Rebecca Limited | Southport | 2014 |
| BY the Word Ltd | Bristol | 2014 |
| BY1 Ltd | Blackpool | 2019 |
| Bybrook Properties Limited | Market Harborough | 2010 |
| Bycrundwell Limited | Tunbridge Wells | 1957 |
| BYE by ME Ltd | Leamington Spa | 2013 |
| BYE Investment Management Ltd | Edinburgh | 2010 |
| BYE Management Limited | Edinburgh | 2009 |
| Byen Drosje Limited | London | 2022 |
| Byes Solar UK Limited | Newcastle Upon Tyne | 2014 |
| BYG Import Investment Limited | London | 2021 |
| Bygeorgia Ltd | Nottingham | 2023 |
| Byggfirma Niclas Forsberg Limited | London | 2010 |
| Byggjobbarn Invest Limited | London | 2025 |
| Byggjobbarn Limited | London | 2025 |
| Byggtrade Limited | London | 2011 |
| Bygmastery Limited | London | 2025 |
| Byjove Media Limited | Horsham | 2016 |
| Byline Investigates Holdings CIC | London | 2021 |
| Bylsborough Estate Limited | Chatham Maritime | 1954 |
| Bynt Co., Limited | London | 2025 |
| Bynt Group Ltd | Chesham | 2026 |
| Byoode.Studio Ltd | Stamford | 2024 |
| Byprem Ltd | Cheshire | 2003 |
| Byram Consultancy Services Ltd | Huddersfield | 2010 |
| Byram Contractors Limited | Manchester | 2021 |
| Byrd Property Solutions Ltd | Westbury | 2024 |
| Byrehope 66 Limited | Broxburn | 2014 |
| Byrne & Co. Ltd | Manchester | 2008 |
| Byrne Consultants Ltd | Brighton | 2024 |
| Byrne Developments Ltd | Chatham | 2021 |
| Byrne PMC Limited | Stratford Upon Avon | 2017 |
| Byrom Street Holdings Limited | Manchester | 2011 |
| Byrom Street Property Limited | Manchester | 2011 |
| Byroms Furnishings (Kendal) Limited | Kendal | 2013 |
| Byron 1962 Limited | Bromsgrove | 2014 |
| Byron 1968 Limited | Manchester | 2014 |
| Byron Digital Ltd | Nottingham | 2020 |
| Byron House Limited | Poole | 1997 |
| Byron Sheet Metal Limited | Nottingham | 1983 |
| Byron Smith Consultancy Ltd | Tadworth | 2022 |
| Byrondale Ltd | Salford | 2003 |
| BYS Petcare Ltd | London | 2025 |
| Bystone Properties Limited | Nelson | 2015 |
| Byte Innovation Ltd | London | 2024 |
| Bytefy Technologies Limited | Croydon | 2024 |
| Byteharbour Digital Ltd | Doncaster | 2025 |
| Bytehouse Limited | Welwyn Garden City | 2008 |
| Bytehub Ltd | Fareham | 2019 |
| Bytequotient UK Ltd | Edinburgh | 2024 |
| Bytes Security Partnerships Limited | Leatherhead | 2001 |
| Bytes Technology Group Holdings Limited | Leatherhead | 2000 |
| Bytes Technology Training Limited | Leatherhead | 1992 |
| Bywater Limited | Esher | 2015 |
| Bywood Celtic Limited | Cardigan | 2005 |
| BYZ Yacht and Consulting Services Ltd | Blackpool | 2024 |
| Bzuk Ltd | Great Yarmouth | 2007 |
| Bøko Ltd | London | 2018 |
| Børge Christian Haaland Limited | Kington | 2024 |