| BCL Property Services Ltd | Real estate | 2023 |
| BCM Baylands Construction Management Limited | Construction | 2017 |
| BCP Developers Limited | Construction | 2022 |
| BCX Limited | Health & social care | 2025 |
| BD Homes Limited | Real estate | 2013 |
| BDS Architecture & Interior Design Limited | Extraterritorial | 2004 |
| BDS Architecture Limited | Professional & scientific | 2013 |
| BDS Imports and Exports Limited | Wholesale & retail | 2008 |
| BDS Vending Solutions Ltd | Wholesale & retail | 2023 |
| Bdul Ltd | Administrative & support | 2025 |
| BE Curious Group Ltd | Financial services | 2026 |
| BE Elite Group Limited | Arts & recreation | 2017 |
| BE Magna Ltd | Extraterritorial | 2025 |
| BE the Lotus Flower Ltd | Agriculture & fishing | 2023 |
| BE Travel Wise Limited | Administrative & support | 2015 |
| Beacon 7 Limited | Other services | 2016 |
| Beadcaresolution Limited | Health & social care | 2023 |
| Beale Close Chippenham Management Company Limited | Households | 1986 |
| Beam Brands Ltd | Manufacturing | 2026 |
| Beamred Limited | Households | 1986 |
| Bearing HIS Image Ltd | Manufacturing | 2025 |
| Beate Uhse Limited | Wholesale & retail | 2002 |
| Beatrice Court (Lichfield) Management Ltd | Households | 2017 |
| Beatrice Property Services Ltd | Real estate | 2020 |
| Beats & Eats CIC | Administrative & support | 2015 |
| Beaufort Flats RES. Assoc. (Twickenham) Limited | Households | 1994 |
| Beaufort Street 129 Limited | Households | 2005 |
| Beaulieu House Limited | Households | 2004 |
| Beaulieu Park T (Chelmsford) Management Limited | Households | 2024 |
| Beaumont Holdings (Sussex) Ltd | Financial services | 2022 |
| Beautech Supplies Ltd | Wholesale & retail | 2025 |
| Beautiful Connections LLP | | 2021 |
| Beautiful Foods Limited | Manufacturing | 2001 |
| Beauty Boost LAB Ltd | Wholesale & retail | 2025 |
| Beauty Bunch Limited | Other services | 2015 |
| Beauty by Patti Ltd | Other services | 2019 |
| Beauty EVO CIC | Administrative & support | 2024 |
| Beauty in Evolution (Beaut.I.E) Limited | Wholesale & retail | 2024 |
| Beauty London Limited | Other services | 2022 |
| Beauty Solutions U.K Ltd | Wholesale & retail | 2023 |
| Beauty World (Croydon) Ltd | Wholesale & retail | 2024 |
| Beaver Architectural Ironmongery Limited | Wholesale & retail | 1999 |
| Beaverglen Limited | Construction | 1972 |
| Beazza Ltd | Wholesale & retail | 2025 |
| Beck Lane, Sutton-In-Ashfield (the Hawthorns) Management Company Limited | Households | 2023 |
| Beckenham Blinds Limited | Wholesale & retail | 2023 |
| Beckenham Junction Limited | Hospitality | 2013 |
| Beckenham Property Management Limited | Real estate | 2021 |
| Beckford Court (Bath) Residents Company Limited | Households | 1994 |
| BED Mattress Furniture Warehouse Ltd | Wholesale & retail | 2020 |
| Beddington Estates Limited | Real estate | 2016 |
| Beddington Land Properties Limited | Real estate | 1987 |
| Bede Group Holdings Limited | Financial services | 2024 |
| Bedford Court Bath Management Company Limited | Households | 1984 |
| Bedir & Co Limited | Professional & scientific | 2016 |
| Bedir Real Estates Limited | Real estate | 2011 |
| Bednia Limited | Wholesale & retail | 2023 |
| BEDS4U Express Limited | Wholesale & retail | 2013 |
| BEDS4ULONDON Ltd | Manufacturing | 2020 |
| BEE Invisible Builders Ltd | Construction | 2018 |
| BEE Invisible ENT Limited | Hospitality | 2014 |
| BEE Quality Cleaning Services UK Limited | Administrative & support | 2025 |
| Beech Court (SE23) Limited | Households | 2011 |
| Beech Court Management (Leytonstone) Limited | Households | 2004 |
| Beechams Mews Management Company Limited | Households | 1992 |
| Beechcroft (Epsom) Freehold Limited | Households | 2007 |
| Beechcroft Place Limited | Households | 2009 |
| Beeches Electrical Limited | Construction | 2022 |
| Beeches Park (Tadworth) Management Company Limited | Households | 2015 |
| Beechwood Farm Management Company Limited | Households | 1984 |
| Beechwood Road Management Limited | Construction | 2014 |
| Beekitchen Consultancy Services Ltd | Administrative & support | 2018 |
| Beersheba 3J'S Ltd | Professional & scientific | 2023 |
| Beesley & Mclean Property Development Ltd | Construction | 2017 |
| Beestars Sports Ltd | Administrative & support | 2025 |
| BEG Management Limited | Construction | 2026 |
| Begley Media Ltd | Information & communication | 2015 |
| Beier Consulting Ltd | Construction | 2025 |
| Bejasata Ltd | Health & social care | 2019 |
| BEL Horizon Ltd | Transport & logistics | 2024 |
| Belair Houses Limited | Hospitality | 2022 |
| Belair Mansion Limited | Hospitality | 2017 |
| Belfield House (Management) Limited | Households | 1964 |
| Belfin Media Limited | Information & communication | 2015 |
| Belgium Rosier Fertilizer Ltd | Administrative & support | 2024 |
| Belgravia Asset Management Limited | Professional & scientific | 2023 |
| Belgravia Court (Horley) Management Company Limited | Households | 1984 |
| Belgravia Village Mart Ltd | Wholesale & retail | 2023 |
| Belhamwood Limited | Real estate | 2002 |
| Belief Global Limited | Professional & scientific | 2006 |
| Bell a Move Ltd | Transport & logistics | 2016 |
| Bell Health Centre Limited | Health & social care | 2020 |
| Bell Hill Close (Billericay) Management Company Ltd | Households | 2012 |
| Bella Italia Horeca Ltd | Hospitality | 2013 |
| Bella Monaire Ltd | Manufacturing | 2025 |
| Bella Park Restaurant Ltd | Hospitality | 2019 |
| Bella Pizza & Kebab Ltd | Hospitality | 2025 |
| Bella Roma (Lewisham) Limited | Hospitality | 2018 |
| Bella Roma Beckenham Limited | Hospitality | 2023 |
| Belle VUE L'Esterre Properties Ltd | Real estate | 2020 |