| Barkers Fibrous Plastering Ltd | Construction | 2024 |
| Barnes Metalwork Ltd | Construction | 2019 |
| Barnview Freehold Limited | Real estate | 2018 |
| Barnview Lodge Management Company Limited | Administrative & support | 1986 |
| Baroda Express Ltd | Hospitality | 2024 |
| Barrack & Fort Property Services Ltd | Construction | 2024 |
| Barrett Services Ltd | Administrative & support | 2025 |
| Barritt Paving Ltd | Construction | 2016 |
| Barsoum Ltd | Households | 2024 |
| Bartonmead Limited | Real estate | 2008 |
| Basilican Pizzeria Ltd | Hospitality | 2026 |
| Batiao Services Limited | Real estate | 2024 |
| Battah Group Ltd | Wholesale & retail | 2025 |
| Baxters International Removals Ltd | Transport & logistics | 2019 |
| Bayer Jack Ltd | Wholesale & retail | 2020 |
| Baylong International Trading Limited | Administrative & support | 2023 |
| Baynhouse Interiors Limited | Construction | 2012 |
| Bayside Technology Limited | Wholesale & retail | 2011 |
| BB Paving Contractors Ltd | Construction | 2020 |
| BCA Ecom Ltd | Wholesale & retail | 2024 |
| BCA Engineering Supplies Ltd | Construction | 2011 |
| BCA Real Estate Limited | Real estate | 2026 |
| Bcmsf Ltd | Professional & scientific | 2023 |
| Bcmsma Ltd | Professional & scientific | 2023 |
| BCMSMA2 Ltd | Professional & scientific | 2025 |
| BD Building Ltd | Construction | 2015 |
| BDL Automotive Ltd | Wholesale & retail | 2014 |
| BE Mgmt Ltd | Professional & scientific | 2019 |
| BE Social Sport Ltd | Professional & scientific | 2024 |
| Beachesandbarbells Ltd | Administrative & support | 2015 |
| Beacon Consulting (London) Limited | Professional & scientific | 2019 |
| Beaney Leisure and Property Developments Limited | Real estate | 2024 |
| Bear Brix Limited | Real estate | 2021 |
| Bearded Bros Exterior Cleaning Ltd | Administrative & support | 2024 |
| Beare Services Ltd | Construction | 2026 |
| Beaundustry Ltd | Wholesale & retail | 2022 |
| Beauty Prima Limited | Other services | 2011 |
| Beauty World Limited | Other services | 2005 |
| BEAUTYBOOTH.B1 Ltd | Other services | 2023 |
| Beavers Trading Ltd | Wholesale & retail | 2019 |
| Bedacre Estates Ltd | Households | 2014 |
| BEE Kind Care Services Ltd | Other services | 2018 |
| Beechwood Avenue 75-81 Property Management Limited | Households | 2003 |
| Beezyy Cashier System Ltd | Information & communication | 2020 |
| Begreen Tableware Ltd | Wholesale & retail | 2023 |
| Beijing New TEC Autoparts Co., Ltd. | Wholesale & retail | 2024 |
| Bejerea Ltd | Construction | 2017 |
| Bella Ceramica Ltd | Construction | 2019 |
| Bellamay Paving and Landscaping Limited | Construction | 2021 |
| BEN Hopkins Motion Ltd | Information & communication | 2015 |
| Bename Finance for Business Ltd | Other services | 2019 |
| Benident Limited | Wholesale & retail | 2010 |
| Benjis Dog Services Limited | Other services | 2024 |
| Bennett Interiors Ltd | Construction | 2021 |
| Bennevest Ltd | Real estate | 2019 |
| Benny Parker Consulting Ltd | Professional & scientific | 2026 |
| Bentley Property Developments Limited | Construction | 2003 |
| Benxi Black Horse Chemical Industry and Commerce Co., Ltd. | Extraterritorial | 2021 |
| Bermandsy Property Limited | Real estate | 2021 |
| Bespoke Furniture Design Limited | Wholesale & retail | 2018 |
| Bespoke Metalwork Drawings Ltd | Professional & scientific | 2019 |
| Bespoke Nurseries Limited | Administrative & support | 2021 |
| Best Budz Ltd | Wholesale & retail | 2018 |
| Best London Removals Ltd | Transport & logistics | 2011 |
| Beston Industry Co., Ltd | Wholesale & retail | 2019 |
| Bestshow International Logistics Co., Ltd | Administrative & support | 2025 |
| Better Websites London Ltd | Information & communication | 2024 |
| Better WIN Co., Ltd | Wholesale & retail | 2014 |
| Betterstore Properties UK Limited | Real estate | 2019 |
| Betterstore Self Storage Holdco 2 Limited | Financial services | 2026 |
| Betterstore Self Storage Operations Limited | Wholesale & retail | 2010 |
| Beyond Wills Limited | Professional & scientific | 2012 |
| Bfht Equity LLP | | 2025 |
| BG Shah Ltd | Wholesale & retail | 2026 |
| BGD Bournemouth Ltd | Real estate | 2024 |
| BGD Motors Ltd | Wholesale & retail | 2024 |
| BHA London Limited | Wholesale & retail | 2019 |
| BHA Trading Limited | Wholesale & retail | 2005 |
| Bharat in UK Ltd | Hospitality | 2024 |
| BHN Maintenance Limited | Construction | 2022 |
| Bien Maritime Co., Ltd | Wholesale & retail | 2021 |
| Bien-Aime Healthcare Ltd | Health & social care | 2025 |
| Bien-Aime HT Ltd | Wholesale & retail | 2025 |
| Big Horse Productions Limited | Information & communication | 2006 |
| Big Lessons Limited | Professional & scientific | 2004 |
| Big S Production Ltd | Information & communication | 2020 |
| Bikini Genie Limited | Administrative & support | 2017 |
| Billi Travels Limited | Administrative & support | 2025 |
| Biloha Ltd | Administrative & support | 2020 |
| Bingham Management Ltd | Extraterritorial | 2014 |
| Bingo Limited | Wholesale & retail | 2004 |
| Binova GT Limited | Wholesale & retail | 2019 |
| Binvank Markets Limited | Financial services | 2022 |
| Binx & Co PR Ltd | Professional & scientific | 2020 |
| Biois UK Ltd | Professional & scientific | 2020 |
| Biotell Limited | Wholesale & retail | 2012 |
| Biozest Ltd | Wholesale & retail | 2026 |
| Bircham & Sons Limited | Construction | 2003 |
| Birla Properties Ltd | Real estate | 2016 |
| Birla Technologies Ltd | Information & communication | 2011 |