| Banfra Ltd | Health & social care | 2017 |
| Banga Medical Services Ltd | Health & social care | 2019 |
| Banks Consulting Ltd | Professional & scientific | 2015 |
| Banner Films Ltd | Information & communication | 2017 |
| Banu 86 Ltd | Transport & logistics | 2017 |
| Banyan Fernhurst Limited | Hospitality | 2013 |
| BAP Supplies Ltd | Wholesale & retail | 2019 |
| Barana Events Ltd | Hospitality | 2023 |
| Barana Travel Ltd | Professional & scientific | 2024 |
| Barazi Antiques Ltd | Wholesale & retail | 2026 |
| Barber and Clarke Limited | Manufacturing | 1998 |
| Barbershop Events Ltd | Other services | 2019 |
| Bardot Films Limited | Other services | 1994 |
| Barileva Trading Ltd | Administrative & support | 2026 |
| Barings Acceptance Limited | Administrative & support | 2010 |
| Barkjump Ltd | Other services | 2025 |
| Barlu-Cons Limited | Construction | 2025 |
| Barn Owls After School Club Ltd | Education | 2004 |
| Barnaby Edward Estates Limited | Professional & scientific | 2018 |
| Barnes Court Residents Company Limited | Real estate | 1967 |
| Baron Bird Holdings Limited | Real estate | 2021 |
| Baron Sauvage Ltd | Information & communication | 2020 |
| Barracuda Restaurant Ltd | Hospitality | 2025 |
| Barrett Productions Limited | Information & communication | 2016 |
| Barros Limited | Wholesale & retail | 2000 |
| Barryanalytics Limited | Information & communication | 2009 |
| Barrys Discount Ltd. | Real estate | 2010 |
| Bars and Melody Limited | Arts & recreation | 2014 |
| Base AI Limited | Information & communication | 2026 |
| Base Beauty Ltd | Health & social care | 2012 |
| Basicidea Group Ltd | Wholesale & retail | 2017 |
| Baskefy Ltd | Professional & scientific | 2022 |
| Bath House Isle of Wight Ltd | Hospitality | 2026 |
| Bathini Construction Limited | Construction | 2025 |
| Batreece Limited | Health & social care | 2016 |
| Baumuster Agencies Ltd | Wholesale & retail | 2012 |
| Bawnogues Rentals (Nine Elms) Limited | Real estate | 2023 |
| Bawnogues Rentals (Putney) Limited | Real estate | 2015 |
| Baxenden Developments Ltd | Construction | 2014 |
| Bay Tree Services Ltd | Health & social care | 2024 |
| Baymire Limited | Health & social care | 2018 |
| Bayt Holding Ltd | Real estate | 2019 |
| Baytracks Limited | Manufacturing | 2011 |
| Baywood Construction Limited | Construction | 2025 |
| Bazar Money Transfer Ltd | Financial services | 2020 |
| Bazi Trans Limited | Wholesale & retail | 2016 |
| BB Licencing UK Ltd | Other services | 2014 |
| BB TRI Office Holdco Limited | Real estate | 2024 |
| Bbgh Limited | Wholesale & retail | 2019 |
| Bbsolutions Ltd | Administrative & support | 2025 |
| BC Security Solutions Ltd | Administrative & support | 2018 |
| BCB Sales Consultancy Limited | Information & communication | 2026 |
| Bcdsocial Ltd | Hospitality | 2022 |
| Bcsupplygroup Ltd | Wholesale & retail | 2026 |
| BDC (69 Mount Park) Limited | Construction | 2024 |
| BDG Client Services Ltd | Other services | 2013 |
| Bdgr Limited | Administrative & support | 2024 |
| BDU Partners LLP | | 2024 |
| Beaconsfield Clinical Services Limited | Health & social care | 2026 |
| Beanward Properties Ltd | Real estate | 2023 |
| Bearic Limited | Real estate | 2022 |
| Bearly Managing Limited | Professional & scientific | 2017 |
| Bears Ambulance Service Limited | Administrative & support | 2009 |
| Bears Property Limited | Real estate | 2019 |
| Beat Play Live Ltd | Arts & recreation | 2024 |
| Beau DEV Limited | Real estate | 2016 |
| Beau Estates Limited | Real estate | 2019 |
| Beauchamp Place (Borehamwood) Management Co Limited | Real estate | 1999 |
| Beaufort House Management Company (RTM) Limited | Professional & scientific | 2004 |
| Beaufort Writing Limited | Arts & recreation | 2002 |
| Beautiful Faces Studio Limited | Other services | 2025 |
| Beautiful Times Ltd | Hospitality | 2019 |
| Beauty Beast Emporium Ltd | Other services | 2023 |
| Beauty by Refresh Ltd | Health & social care | 2024 |
| Beauty Edit Mayfair Limited | Administrative & support | 2017 |
| Beauty Innovations Ltd | Wholesale & retail | 2024 |
| Beauty Wholesale Limited | Wholesale & retail | 1999 |
| Beck Logistics LLP | | 2016 |
| Becketts Developments Limited | Administrative & support | 2018 |
| Bede Services Ltd | Construction | 2016 |
| Bedford House Management Company (RTM) Limited | Professional & scientific | 2004 |
| Bedford Investment Company 2 Limited | Real estate | 2014 |
| Bedford Noodle Bar Ltd | Hospitality | 2023 |
| Bedford Roofing Limited | Construction | 2024 |
| Bedrock 530 Fifth Ltd | Financial services | 2021 |
| BEE Original Studios Ltd | Administrative & support | 2016 |
| Bee's Knees Interiors Limited | Other services | 2016 |
| Beebeezee Limited | Information & communication | 2011 |
| Beeches Carpentry Ltd | Manufacturing | 2010 |
| Beeches Freehold Ltd | Real estate | 2006 |
| Beehix Asset Ltd. | Administrative & support | 2010 |
| Beeplar Holdings (UK) Limited | Financial services | 2024 |
| Beewood Services Limited | Information & communication | 2021 |
| Begu Construction Ltd | Construction | 2020 |
| Behindthecurtainuk Ltd | Other services | 2021 |
| Bejojo Ltd | Health & social care | 2014 |
| Bela Contractors Ltd | Construction | 2024 |
| Belfon Ltd | Wholesale & retail | 2021 |
| Belgrave Superstore Ltd | Wholesale & retail | 2019 |
| Belgravia 1 Limited | Extraterritorial | 2020 |