| Bdfive Ltd | Real estate | 2024 |
| BDN Vehicle Services Ltd | Transport & logistics | 2014 |
| BE YOU Build Ltd | Construction | 2026 |
| Beak & Mane Ltd | Real estate | 2024 |
| Beaman Glass (London) Limited | Wholesale & retail | 1993 |
| Bean Gone Limited | Hospitality | 2025 |
| Beatbuzz Ltd | Administrative & support | 2015 |
| Beatbuzz Records Ltd | Arts & recreation | 2018 |
| Beauty Space London Ltd | Other services | 2026 |
| Beautyme Media Limited | Professional & scientific | 2016 |
| Bebbington Property Management Limited | Households | 2013 |
| Beck Wealth Management Ltd | Financial services | 2016 |
| BEE Harmony Ltd | Transport & logistics | 2023 |
| BEE Mobile Limited | Wholesale & retail | 2005 |
| Beef'D Ltd | Hospitality | 2022 |
| Bekka Talents Ltd | Administrative & support | 2025 |
| Belgravia Secretarial Services Limited | Administrative & support | 1997 |
| Bella Rose Beauty Ltd | Other services | 2019 |
| Bellasmgt Ltd | Professional & scientific | 2025 |
| Bellenie Investments Ltd | Real estate | 2021 |
| Belo Interiors Ltd | Construction | 2023 |
| BEN Holmes Consultancy Ltd | Professional & scientific | 2024 |
| Benchmark Fitness & Nutrition Ltd | Other services | 2016 |
| Benchmark Property Investments Ltd | Real estate | 2021 |
| Bendrum Solutions Limited | Information & communication | 2015 |
| Benfleet Accounts Ltd | Professional & scientific | 2019 |
| Benfleet Bookkeepers Ltd | Professional & scientific | 2023 |
| Benfleet Building and Garden Supplies Ltd | Extraterritorial | 2014 |
| Benfleet Building Services Ltd | Construction | 2020 |
| Benfleet Building Supplies Ltd | Extraterritorial | 2011 |
| Benfleet Counselling and Psychotherapy Ltd | Health & social care | 2020 |
| Benfleet Fashion Ltd | Wholesale & retail | 2024 |
| Benfleet Garden Centre Ltd | Extraterritorial | 2011 |
| Benfleet Glass Co Limited | Construction | 1964 |
| Benfleet Meat & VEG Limited | Wholesale & retail | 2024 |
| Benfleet Property Services Limited | Real estate | 2023 |
| Benfleet Reclaim and Garden Centre Limited | Extraterritorial | 2014 |
| Benfleet Reclaim Ltd | Extraterritorial | 2011 |
| Benfleet Reclamation Ltd | Extraterritorial | 2011 |
| Benfleet Skips Limited | Extraterritorial | 2012 |
| Benfleet Technical Services Limited | Construction | 1999 |
| Benfleet Timber Supplies Ltd | Extraterritorial | 2017 |
| Benfleetvets Ltd | Professional & scientific | 2015 |
| Bennett Property Investments Ltd | Real estate | 2018 |
| Bentley Fire Protection Ltd | Public administration | 2023 |
| Bentley Padel Club Limited | Arts & recreation | 2026 |
| Bentrans 247 Limited | Transport & logistics | 2017 |
| Ben’S Bugs Pest Control Ltd | Administrative & support | 2021 |
| Besni 02 Ltd | Hospitality | 2025 |
| Bespoke by Tobias Limited | Construction | 2024 |
| Bespoke Cabinets Ltd | Manufacturing | 2023 |
| Best & Co Properties Limited | Real estate | 2018 |
| Best Cars 4U Ltd | Wholesale & retail | 2026 |
| Best Day Ever Company Limited | Wholesale & retail | 2016 |
| Best Deals Trading Ltd | Wholesale & retail | 2020 |
| Better Bodies Personal Training Limited | Arts & recreation | 2014 |
| Betterbuild South West Limited | Construction | 2021 |
| Bevel Homes Ltd | Real estate | 2019 |
| Bewley Contracts (UK) Ltd | Construction | 2012 |
| Beyoutifful Homes Ltd | Real estate | 2020 |
| Beyoutifful Ltd | Other services | 2018 |
| BFW Consulting Limited | Information & communication | 2021 |
| BG Independent Social Work Services Ltd | Health & social care | 2023 |
| BG Therapy Group Limited | Health & social care | 2025 |
| BH Property Portfolio Limited | Hospitality | 2026 |
| BHC Accounting Limited | Professional & scientific | 2019 |
| Bickford Builders Ltd | Construction | 2021 |
| Big D Self Storage Limited | Other services | 2014 |
| Big Field Investments Ltd | Real estate | 2023 |
| Big Love Foundation | Health & social care | 2015 |
| Big Reach Media UK Ltd | Professional & scientific | 2025 |
| Bighills Ltd | Real estate | 2023 |
| Bigrick Properties Ltd | Real estate | 2025 |
| Bilk Nutrition Limited | Wholesale & retail | 2025 |
| Billericay Tyres Ltd | Wholesale & retail | 2011 |
| Binary PR and Marketing Ltd | Professional & scientific | 2025 |
| Bingham Precision Engineers Limited | Professional & scientific | 2003 |
| Biosphere Technology Limited | Professional & scientific | 2014 |
| Birmingham Bailiff Services Ltd | Other services | 2021 |
| Biznas Ltd | Administrative & support | 2020 |
| BJB Leicester Ltd | Hospitality | 2025 |
| BJH Buildings Ltd | Construction | 2024 |
| BK James Limited | Construction | 2009 |
| BKR (Thames Gateway) Properties Ltd | Real estate | 2009 |
| Black Lion Films Limited | Information & communication | 2008 |
| Blackmore Tea Rooms Limited | Hospitality | 2023 |
| Blank Canvas Lasers Limited | Other services | 2014 |
| Blend Development Consultancy Ltd | Professional & scientific | 2020 |
| Blended Investments Ltd | Real estate | 2022 |
| Blended Properties Ltd | Real estate | 2021 |
| Blessed GEN Cleaning Service Ltd | Administrative & support | 2023 |
| Bleu Delta Investments Limited | Real estate | 2022 |
| Blonde DYE Bleach Limited | Other services | 1997 |
| Bloom in Doom Ltd | Information & communication | 2020 |
| Bloomdisplay Limited | Professional & scientific | 2002 |
| BLS Flooring Limited | Construction | 2023 |
| BLU Genie Records Ltd | Arts & recreation | 2020 |
| BLU Nuvo Limited | Other services | 2015 |
| Blue Beau Prom and Bridal Limited | Wholesale & retail | 2016 |
| Blue Circle Corporation Ltd | Financial services | 2026 |