| Blue Valley Estates Ltd | Real estate | 2017 |
| Bluebell Data Ltd | Information & communication | 2020 |
| Bluebell Place Limited | Health & social care | 2013 |
| Bluebells Care Group Ltd | Health & social care | 2025 |
| Bluebells Home Limited | Health & social care | 2025 |
| Bluebelt Investments Ltd | Real estate | 2024 |
| Bluebridge One Business Solutions Limited | Information & communication | 2003 |
| Bluebridge One Cloudapps Limited | Information & communication | 2022 |
| Bluebridge One Group Limited | Information & communication | 2022 |
| Bluecap Digital Ltd | Information & communication | 2018 |
| Bluechip Enterprise Inc. Limited | Other services | 2015 |
| Bluecircuit Tech Ltd | Construction | 2025 |
| Bluecon Limited | Professional & scientific | 2016 |
| Bluecroft Estates Limited | Health & social care | 2006 |
| Bluefalls Limited | Administrative & support | 2015 |
| Blueheart Limited | Extraterritorial | 1999 |
| Blueink Partner Ltd | Transport & logistics | 2025 |
| Bluejay Construction Limited | Construction | 2003 |
| Blueleaf Investments Ltd. | Real estate | 2022 |
| Blueline Car Hire Ltd | Administrative & support | 2019 |
| Bluemont Assets Limited | Real estate | 2025 |
| Bluenova Care Ltd | Health & social care | 2025 |
| Blueoak Technologies Ltd | Information & communication | 2025 |
| Bluerock Scrap Ltd | Wholesale & retail | 2026 |
| Blueskye Associates Ltd | Extraterritorial | 2011 |
| Bluestar Alliance Limited | Real estate | 2024 |
| Bluestech Limited | Real estate | 1983 |
| Bluestone Estates Mayfair Limited | Administrative & support | 2011 |
| Bluestone Holdings Limited | Real estate | 2025 |
| Bluestone of London Ltd | Financial services | 2014 |
| Bluethroat Ltd | Construction | 2026 |
| Bluethyme Limited | Professional & scientific | 2010 |
| Bluewater (London) Properties Ltd | Real estate | 2018 |
| Bluey Holdings Limited | Health & social care | 2025 |
| Blumin Capital Ltd | Real estate | 2012 |
| Blunt Heights Ltd | Real estate | 2025 |
| Blupack Limited | Wholesale & retail | 2020 |
| Blurred Persona Limited | Wholesale & retail | 2025 |
| Blusens Limited | Information & communication | 2014 |
| Blush and Gold Limited | Wholesale & retail | 2016 |
| Blushadow Ltd | Wholesale & retail | 2025 |
| BM Accountants Ltd | Professional & scientific | 2014 |
| BM Care Limited | Other services | 2003 |
| BM Films Ltd | Information & communication | 2024 |
| BM GAL Limited | Information & communication | 2024 |
| BM Immigration Ltd | Professional & scientific | 2019 |
| BM London Limited | Professional & scientific | 2011 |
| BM88 Limited | Other services | 2014 |
| BMA & Co Group Ltd | Financial services | 2019 |
| Bmar Services Limited | Professional & scientific | 2017 |
| BMB Direct Ltd | Professional & scientific | 2020 |
| BMB UKR Construction Ltd | Construction | 2022 |
| Bmcm Films Ltd | Information & communication | 2020 |
| Bmcraft Ltd | Manufacturing | 2022 |
| BMG Gourmet Ltd | Hospitality | 2019 |
| BMG London Ltd | Financial services | 2022 |
| BMG Southern Limited | Real estate | 2025 |
| BMH Relocation Limited | Extraterritorial | 2014 |
| BMI Plumbing Ltd | Construction | 2019 |
| BMJ Logistics Ltd | Transport & logistics | 2022 |
| BMJ Waste Limited | Water & waste | 2012 |
| BML Private Finance Limited | Financial services | 2019 |
| BMM Cars Ltd | Administrative & support | 2026 |
| BMS Employment Ltd | Administrative & support | 2017 |
| BMS Trading Europe Ltd | Professional & scientific | 2018 |
| Bmtv Anglo American Limited | Information & communication | 2023 |
| Bmtv Limited | Information & communication | 2023 |
| Bmxcon Ltd | Construction | 2019 |
| Bmyi Limited | Health & social care | 2025 |
| BN4 Limited | Construction | 2025 |
| BND Transport Ltd | Transport & logistics | 2025 |
| Bngscreeding Ltd | Construction | 2023 |
| BNM Consultancy Ltd | Information & communication | 2024 |
| BNN Transport Ltd | Transport & logistics | 2023 |
| Bntk Properties Ltd | Real estate | 2025 |
| BNZ Luxury World Ltd | Administrative & support | 2026 |
| Bnzuri Emporium Limited | Professional & scientific | 2020 |
| Bo.Ro Constructions Ltd | Administrative & support | 2020 |
| BOA Consultancies Ltd | Health & social care | 2020 |
| Boanca Enterprise Ltd | Construction | 2023 |
| Boasy Ltd | Administrative & support | 2018 |
| Boatmove Ltd | Transport & logistics | 2026 |
| BOB Brickwork Ltd | Construction | 2026 |
| BOB Interiors Ltd | Construction | 2016 |
| BOB Maynard Consulting Limited | Administrative & support | 2023 |
| BOB Spedition Ltd | Other services | 2015 |
| BOB Weaver Engineering Surveys Limited | Professional & scientific | 2011 |
| Bob's Construction Ltd | Construction | 2018 |
| Boba Luxx Limited | Wholesale & retail | 2023 |
| Boba Tea Life Ltd | Hospitality | 2021 |
| Bobb & Cole Limited | Wholesale & retail | 2010 |
| Bobby and Sons Heating and Plumbing Ltd | Construction | 2026 |
| Boberry Ltd | Hospitality | 2025 |
| Bobut Builders Limited | Construction | 2008 |
| Bock & Partners Ltd | Professional & scientific | 2019 |
| Bodean Contractors Ltd | Construction | 2025 |
| Body & Paint Solutions Ltd | Wholesale & retail | 2022 |
| Body Buzz Limited | Health & social care | 2000 |
| Body Conscious Conditioning Ltd | Health & social care | 2013 |
| Body Conscious Training Ltd | Arts & recreation | 2021 |