| Bloomsfield Recruitment Consultant Ltd | Administrative & support | 2025 |
| Bloomsfield Specialist Care Limited | Real estate | 2024 |
| Blossom High Limited | Health & social care | 2021 |
| Blue Hawk Limited | Real estate | 2024 |
| Blue Moon Berkshire Ltd | Hospitality | 2021 |
| Blue Orchid Care Ltd | Health & social care | 2023 |
| Blue Square Partnership LLP | | 2025 |
| Blux UK Import Ltd | Wholesale & retail | 2015 |
| BMN Properties Limited | Real estate | 2021 |
| Bmnc Consulting Ltd | Information & communication | 2020 |
| BMQ Group Ltd | Financial services | 2025 |
| BMV Houses Limited | Real estate | 2017 |
| BMW Customz Ltd | Manufacturing | 2021 |
| Bobby's Fish (NO. 2) Limited | Wholesale & retail | 2024 |
| Bodapel Limited | Real estate | 2020 |
| Bodywork Specialists Ltd | Wholesale & retail | 2025 |
| Boffin Clinical Ltd | Professional & scientific | 2023 |
| Bojis Properties Limited | Real estate | 2023 |
| Boltowem Luxury Events Ltd | Hospitality | 2017 |
| Boncu G Transport Ltd | Transport & logistics | 2017 |
| Bonorum Management Services Limited | Professional & scientific | 2019 |
| Boogeyman Ltd | Transport & logistics | 2017 |
| Bookaparcel Ltd | Transport & logistics | 2011 |
| Bookbuddi Ltd | Wholesale & retail | 2021 |
| Boost Managed Services Ltd | Energy | 2026 |
| Booth White Project Management Limited | Real estate | 2022 |
| Booze House Tales Limited | Wholesale & retail | 2020 |
| Borz Jewels Ltd | Wholesale & retail | 2023 |
| Boss's Lunch Box Limited | Hospitality | 2019 |
| Boutique Cake Studio Ltd | Manufacturing | 2013 |
| Box Halo Limited | Information & communication | 2020 |
| Box IT Store IT Limited | Transport & logistics | 2026 |
| Box Sale Ltd | Wholesale & retail | 2018 |
| BP Bear Holdings Ltd | Financial services | 2022 |
| BP Bear Investments Ltd | Real estate | 2023 |
| BPC AV Limited | Construction | 2015 |
| BPL Interiors Ltd | Construction | 2017 |
| Brad Gladden Glazing Ltd | Construction | 2022 |
| Brafaz UK Limited | Professional & scientific | 2014 |
| Braj Care Solutions Limited | Information & communication | 2023 |
| Brand Healthcare Services Ltd | Health & social care | 2015 |
| Branded Production Limited | Manufacturing | 2023 |
| Bredhurst Training Services Ltd | Education | 2013 |
| Brentwood Aquatic & Pet Centre Ltd | Wholesale & retail | 2025 |
| Bretons Manor Ltd. | Hospitality | 2022 |
| Brides Walking the Runway Ltd | Wholesale & retail | 2021 |
| Bridgelink Consulting Limited | Real estate | 2026 |
| Bright Sparks Engineering Services Limited | Wholesale & retail | 2010 |
| Brighter Developments Ltd | Construction | 2022 |
| Brightviewdoors Ltd | Manufacturing | 2025 |
| Brilliant Care Services Ltd | Health & social care | 2023 |
| Brilliant Roofing Limited | Construction | 2017 |
| Brimglades Limited | Manufacturing | 1971 |
| Brims Services Ltd | Health & social care | 2019 |
| Brit Heights Ltd | Real estate | 2026 |
| Britmarthub (UK) Ltd | Wholesale & retail | 2025 |
| Britwood Creations Ltd | Construction | 2026 |
| Broadview Financials Limited | Professional & scientific | 2018 |
| Brother's Double Glazing Ltd | Construction | 2022 |
| Brothers STS Limited | Transport & logistics | 2016 |
| Bruce Global Ltd | Construction | 2020 |
| Btech Digital Limited | Wholesale & retail | 2022 |
| Bubble Consultancy Limited | Wholesale & retail | 2021 |
| Bubble Way Car Wash Limited | Administrative & support | 2025 |
| Bubbles Vehicle Services and Car Sales Ltd | Administrative & support | 2025 |
| Budget Property Investment Ltd | Real estate | 2020 |
| Budget Windscreens (Bedford) Limited | Wholesale & retail | 1996 |
| Buena Vista Management Consultants LLP | | 2010 |
| BUILD24 Ltd | Construction | 2013 |
| Building Analysis Ltd | Professional & scientific | 2025 |
| Building Design & Renovations Ltd | Construction | 2026 |
| Builtt Ltd | Construction | 2024 |
| Bukken Estate Limited | Real estate | 2021 |
| Bukliz Steps Limited | Health & social care | 2025 |
| Bunno Services Limited | Real estate | 2020 |
| Buns & Wings Limited | Hospitality | 2025 |
| Burger HQ Ltd | Hospitality | 2025 |
| Burke Demolition Ltd | Construction | 2019 |
| Burke Environmental Services Ltd | Professional & scientific | 2024 |
| Butler-Aggrey & Co Ltd | Construction | 2015 |
| Buy 2 LET Trucks Ltd | Transport & logistics | 2015 |
| Buy&Sell&Trade Ltd | Wholesale & retail | 2025 |
| Buzz Bear Pubs Ltd | Hospitality | 2023 |
| Buzz Grill Contemporary Indian Cuisine Ltd | Hospitality | 2019 |
| Buzzbee Handyman Solutions Ltd | Other services | 2024 |
| BVF Plumbing and Heating Ltd | Construction | 2026 |
| Bytecode Software Solutions Ltd | Information & communication | 2018 |
| C&S Freight Services Ltd | Transport & logistics | 2017 |
| C.B Offiah & S.A Sani Enterprise Ltd | Health & social care | 2024 |
| C.C.Rus Ltd | Construction | 2017 |
| C.E. Uzozie Ltd | Health & social care | 2021 |
| Cabana Pollo Ltd | Hospitality | 2024 |
| Cabo Investments Ltd | Real estate | 2025 |
| Caboalto Ltd | Professional & scientific | 2025 |
| Cafe Chai Leyton Ltd | Hospitality | 2026 |
| Cafe HUM Ltd | Hospitality | 2025 |
| Cafe the HUT Elephant & Castle Ltd | Hospitality | 2024 |
| Cafe the HUT Gatwick Ltd | Hospitality | 2024 |
| Cafe the HUT Ltd | Hospitality | 2024 |
| Caine's Pizza Ltd | Hospitality | 2023 |