| B & N Minerals Ltd | Manufacturing | 2025 |
| B & Sons Property Ltd | Real estate | 2022 |
| B and S Housing Solutions Ltd | Real estate | 2024 |
| B Crystal Limited | Transport & logistics | 2013 |
| B Emerald Limited | Transport & logistics | 2013 |
| B K Plumbing (London) Ltd | Construction | 2021 |
| B K Rabadiya Construction Ltd | Construction | 2005 |
| B M Management Services Ltd | Professional & scientific | 2023 |
| B R Patel Holdings Limited | Real estate | 2018 |
| B&M Bags Ltd | Wholesale & retail | 2025 |
| B&M Capital Investment Ltd. | Professional & scientific | 2015 |
| B'N'H Accounting Solutions Limited | Professional & scientific | 2006 |
| B-Floconsultancy Limited | Administrative & support | 2016 |
| B.A.Z. Management Limited | Wholesale & retail | 2010 |
| B.L. Joshi UK Limited | Wholesale & retail | 1983 |
| B.P.Hughes Limited | Professional & scientific | 1985 |
| B12 Group Ltd | Administrative & support | 2025 |
| BA INT Ltd | Transport & logistics | 2008 |
| Baara Masale Limited | Wholesale & retail | 2025 |
| Baba Auto Centre Ltd | Wholesale & retail | 2017 |
| Baba Autos & MOT Ltd | Wholesale & retail | 2024 |
| Baba Peer Ltd | Wholesale & retail | 2025 |
| Babber and Johnson Private Medical Services Ltd | Health & social care | 2026 |
| Bablas Limited | Wholesale & retail | 2008 |
| Babulal Paanwala Ltd | Wholesale & retail | 2025 |
| Baby Face Ltd | Other services | 2024 |
| Babylon Bakery Limited | Manufacturing | 2012 |
| Babylon Bar & Restaurant Ltd | Hospitality | 2024 |
| Babylon Car Limited | Wholesale & retail | 2025 |
| Babylon Emporium Ltd | Wholesale & retail | 2019 |
| Babylon Estate Limited | Real estate | 2019 |
| Babylon Investment & General Contracting and Trading UK Ltd | Construction | 2024 |
| Babz Tutors Ltd | Education | 2025 |
| Back 4 Health Ltd | Health & social care | 2023 |
| Back to Balance (UK) Limited | Health & social care | 2004 |
| Bada Business Limited | Wholesale & retail | 2019 |
| Baddar Ahmed Ltd | Transport & logistics | 2026 |
| Bademah Developments Ltd | Construction | 2025 |
| Badi Trading Limited | Administrative & support | 2012 |
| Badshah Korner Ltd | Wholesale & retail | 2023 |
| BAE Education Ltd | Education | 2023 |
| Baffoe Galaxy Limited | Wholesale & retail | 2025 |
| Baga Ethnik Living UK Ltd | Wholesale & retail | 2025 |
| Bagshot Shipping Limited | Transport & logistics | 2023 |
| Bagwan Limited | Manufacturing | 2025 |
| Baharistan Ice Cream Ltd | Manufacturing | 2024 |
| Bahta Ltd | Administrative & support | 2016 |
| Bahu Medics Ltd | Health & social care | 2022 |
| Bahuchar Importers Limited | Hospitality | 2025 |
| Baike Ltd | Wholesale & retail | 2023 |
| Baked Art Ltd | Manufacturing | 2014 |
| Baker Street Stall Ltd | Wholesale & retail | 2022 |
| Bala Lettings Ltd | Real estate | 2013 |
| Bala Meat Market Ltd | Wholesale & retail | 2020 |
| Balajee Enterprises Ltd | Transport & logistics | 2012 |
| Balaji Gallery Dental Practice Limited | Health & social care | 2022 |
| Balaji Gallery Property Limited | Health & social care | 2022 |
| Balaji Holdings Ltd | Health & social care | 2022 |
| Balaji IT Consultants Limited | Information & communication | 2010 |
| Balan ADO Building Limited | Construction | 2017 |
| Balanced Accounts Ltd | Professional & scientific | 2022 |
| Balash Inc Ltd | Wholesale & retail | 2024 |
| Baldeo Group Ltd | Real estate | 2023 |
| Baldini SRL (Italy) Ltd | Wholesale & retail | 2026 |
| Baldock Operations Ltd | Construction | 2024 |
| Baldomero Ltd | Financial services | 2024 |
| Balham Shipping Limited | Transport & logistics | 2025 |
| Ball OUT the Box Ltd | Arts & recreation | 2021 |
| Balloons and YOU Ltd | Hospitality | 2023 |
| Balustrad Ltd | Construction | 2018 |
| Balysse Limited | Transport & logistics | 2018 |
| Bamford Anaesthetic Services Limited | Health & social care | 2011 |
| Bamford Homes UK Ltd | Health & social care | 2009 |
| Bana Caterers Ltd | Hospitality | 2008 |
| Banamali Dash UK Ltd | Real estate | 2017 |
| Banday Limited | Professional & scientific | 2010 |
| Bandb Assets Limited | Real estate | 2021 |
| Banein Limited | Real estate | 2019 |
| BANG1N Ltd | Hospitality | 2018 |
| Bangalore Dosa Corner Limited | Hospitality | 2026 |
| Bangla Bazaar (2009) Limited | Other services | 2009 |
| Bank House Lockers Limited | Administrative & support | 1992 |
| Bansal & Sons Ltd | Real estate | 2021 |
| Bansal Aviation Ltd | Real estate | 2020 |
| Banty Properties Limited | Real estate | 2016 |
| Bapm Norbury Foods Ltd | Wholesale & retail | 2016 |
| Bara Masale Ltd | Hospitality | 2024 |
| Barakah Fitness Ltd | Arts & recreation | 2023 |
| Baran Commercial Furniture Ltd | Manufacturing | 2025 |
| Barbosa & SON Limited | Real estate | 2026 |
| Bare Ice London Ltd | Manufacturing | 2019 |
| Bareflights Limited | Professional & scientific | 2024 |
| Barg Engineering Ltd | Wholesale & retail | 2011 |
| Barg Japan Ltd | Wholesale & retail | 2025 |
| Barg Motors Ltd | Wholesale & retail | 2019 |
| Barn Hill Accounting Ltd | Professional & scientific | 2011 |
| Barn Hill Estates Limited | Real estate | 2025 |
| Barrel Chase Estate Agents Ltd | Real estate | 2019 |
| Barrenny Tenants Company Limited | Real estate | 1960 |
| Barrington Care Group Limited | Health & social care | 2020 |