| Blumera Group Ltd | Wholesale & retail | 2026 |
| Blunt Hairstyling Ltd | Other services | 2019 |
| Blusterous (UK) Onshore Wind Project SPV Ltd | Construction | 2025 |
| Blusterous Limited | Professional & scientific | 2021 |
| Bluville Ltd | Hospitality | 2022 |
| Blvck Mvsquervde International Records and Management Limited | Wholesale & retail | 2025 |
| Blymp Ltd | Information & communication | 2024 |
| BM Cozma Ltd | Health & social care | 2022 |
| BM Oncology Ltd | Health & social care | 2020 |
| BM Teamsters Ltd | Wholesale & retail | 2014 |
| BMA Bristol Limited | Financial services | 2015 |
| BMB Domestic Services Limited | Professional & scientific | 2017 |
| Bmbprops Ltd | Real estate | 2023 |
| Bmcelectricalserviceuk Limited | Construction | 2022 |
| BMD Global Limited | Professional & scientific | 2004 |
| BME Projects Ltd | Construction | 2024 |
| BMK Management Limited | Professional & scientific | 2013 |
| BMO Academy Limited | Manufacturing | 2012 |
| BMS (LDN) Limited | Construction | 2019 |
| Bmth Property Management Ltd | Real estate | 2024 |
| Bmvpainters Limited | Construction | 2025 |
| BNC Poole Ltd | Real estate | 2023 |
| BNG Logistics Limited | Administrative & support | 2017 |
| Bngu Limited | Other services | 2021 |
| BO Boutique Limited | Extraterritorial | 2012 |
| Bo'Ness HR Limited | Professional & scientific | 2024 |
| Bo-Ness Limited | Real estate | 2020 |
| Board Your Loft UK Ltd | Construction | 2025 |
| Boardzie Limited | Professional & scientific | 2025 |
| Boat Club Trafalgar Limited | Manufacturing | 2018 |
| Boatyard Cottages Ltd | Financial services | 2024 |
| Bob's Vinyl Ltd | Wholesale & retail | 2025 |
| Bobbys Parlour Ltd | Hospitality | 2023 |
| Bocro Group Ltd | Construction | 2025 |
| Bodorgan Court Management Limited | Households | 1984 |
| Bodorgan Road Management Company Limited | Households | 1997 |
| Bodrum Barbers BH9 Ltd | Other services | 2026 |
| Body Refurb Limited | Health & social care | 2007 |
| Bodysnatchers Boxing Ltd | Other services | 2019 |
| Bodytorque Cars Limited | Wholesale & retail | 2003 |
| Boer Cosmetics Ltd | Other services | 2023 |
| Boew Investments Limited | Real estate | 2019 |
| BOH Dance Ltd | Education | 2025 |
| BOH Studios Ltd | Hospitality | 2024 |
| Bohdi Studio Ltd | Wholesale & retail | 2025 |
| Bohen Services Ltd | Construction | 2022 |
| Boho Buffalo Limited | Manufacturing | 2026 |
| Bokkies Kombuis Ltd | Wholesale & retail | 2026 |
| Bokkies Meat Co. Ltd | Manufacturing | 2026 |
| BOL Investments Limited | Real estate | 2016 |
| BOL2 Limited | Professional & scientific | 2021 |
| Bold & Beauty Studio Ltd | Other services | 2023 |
| Bollingwood Limited | Administrative & support | 2004 |
| Bolshop Ltd | Wholesale & retail | 2025 |
| Bolt Consulting LLP | | 2007 |
| Bolt Portfolio Ltd | Real estate | 2004 |
| Bolton and Leurs Ltd | Health & social care | 2018 |
| Bolton Court Management Company Limited | Households | 2019 |
| Bomba Cluck Ltd | Hospitality | 2025 |
| Bombproof Boxer Ltd | Other services | 2021 |
| Bombshell Chic Limited | Wholesale & retail | 2015 |
| Bomo Audio Studios Limited | Information & communication | 2025 |
| Bomo Roast Ltd | Wholesale & retail | 2024 |
| Bomo Sunglasses Limited | Wholesale & retail | 2018 |
| BON Dabang Ltd | Hospitality | 2023 |
| Bond's Basingstoke Limited | Other services | 2024 |
| Bond's Bournemouth Limited | Other services | 2024 |
| Bond's Broadstone Limited | Other services | 2024 |
| Bond's Brockenhurst Ltd | Other services | 2022 |
| Bond's Fordingbridge Limited | Other services | 2024 |
| Bond's Lymington Ltd | Other services | 2022 |
| Bond's Poole Limited | Other services | 2024 |
| Bond's Products Ltd | Other services | 2025 |
| Bond's Wareham Limited | Other services | 2024 |
| Bond's Winchester Ltd | Other services | 2025 |
| Bondabang Family Ltd | Hospitality | 2025 |
| Bondco 777 Limited | Financial services | 2014 |
| Bondtek Productions Ltd | Arts & recreation | 2018 |
| Bonface Ltd | Health & social care | 2024 |
| Bonita Brazil Aesthetics Ltd | Other services | 2024 |
| Bonnin Percival Investments Limited | Real estate | 2023 |
| Bonomosurgical Limited | Health & social care | 2021 |
| Boochacha Ltd | Wholesale & retail | 2021 |
| Booji 1 Management Limited | Real estate | 2025 |
| Booji 2 Management Limited | Real estate | 2025 |
| Book Lombok Ltd | Administrative & support | 2026 |
| Boom Global Consulting Limited | Professional & scientific | 2019 |
| Boom Media Ltd | Professional & scientific | 2021 |
| Boom Property Investments Ltd | Real estate | 2023 |
| Boomerang Health Limited | Health & social care | 2015 |
| Boost Evaluation Limited | Professional & scientific | 2011 |
| Boost Marketing Limited | Professional & scientific | 2006 |
| Bootleg Liquor Ltd | Administrative & support | 2014 |
| Born Bilingual Ltd | Professional & scientific | 2018 |
| Borntolead Ltd | Professional & scientific | 2026 |
| Boro Experiences Limited | Administrative & support | 2018 |
| Borthwick Freehold Limited | Households | 2004 |
| Borussia Dortmund FAN Club London Ltd. | Information & communication | 2019 |
| Borzac Limited | Real estate | 2002 |
| Bosc Vegas Ltd | Wholesale & retail | 2013 |