| Benjac LLP | | 2010 |
| Benjamin House Residents Association Limited | Households | 1994 |
| Benjamina Ebuehi Limited | Hospitality | 2021 |
| Benkei Finance Ltd | Financial services | 2025 |
| Benkei Holdings Ltd | Financial services | 2025 |
| Benkei Investments Ltd | Financial services | 2025 |
| Bennett’S Heating and Plumbing Ltd | Construction | 2024 |
| Benoni Ltd | Professional & scientific | 2020 |
| Bentagh Limited | Information & communication | 2018 |
| Bentley Logistics Limited | Transport & logistics | 2023 |
| Bentleys of Amersham Ltd | Other services | 2022 |
| Bentleys of Hazlemere Ltd | Other services | 2023 |
| Benton Stunts Limited | Arts & recreation | 2023 |
| Beowulf Infrastructure Ltd | Construction | 2012 |
| Berks Construction and Maintenance Ltd | Construction | 2022 |
| Bermudair UK Limited | Administrative & support | 2023 |
| Berry Good Ltd | Wholesale & retail | 2025 |
| Bespoke 1 Limited | Wholesale & retail | 2021 |
| Bespoke Airsoft Retail Ltd | Wholesale & retail | 2018 |
| Bespoke Cycling Instruction Ltd | Education | 2017 |
| Bespoke Merchandise Limited | Wholesale & retail | 2011 |
| Bessemer Drive Limited | Real estate | 2025 |
| Best Bites Beaconsfield Limited | Hospitality | 2019 |
| Best House Property Ltd | Real estate | 2025 |
| Best Mindset Ltd | Professional & scientific | 2019 |
| Best Possible Leader Limited | Education | 2021 |
| Best Possible Leadership Limited | Extraterritorial | 2021 |
| Best Sizzler Limited | Manufacturing | 2022 |
| Best Solution for U Limited | Construction | 2020 |
| Best Sunbeds Holdings Limited | Financial services | 2024 |
| Best Sunbeds Ltd | Administrative & support | 2014 |
| Bestpricewholesale Ltd | Wholesale & retail | 2025 |
| Beswick Holdings Ltd | Financial services | 2018 |
| Beta Dogs (Plymouth) Ltd | Other services | 2021 |
| Beta Dogs UK Ltd | Other services | 2020 |
| Beta Valve Employee Trustee Limited | Professional & scientific | 2017 |
| Beta Valve Systems Ltd | Wholesale & retail | 1983 |
| Betabuild Ltd | Construction | 2023 |
| Beth's Budget Diary Limited | Wholesale & retail | 2024 |
| Betr Realty Ltd | Real estate | 2023 |
| Better Aerobatics Ltd | Professional & scientific | 2019 |
| Better Beard Ltd | Extraterritorial | 2013 |
| Better Brows Limited | Administrative & support | 2011 |
| Better Decor Ltd | Construction | 2024 |
| Better Than New Music Limited | Wholesale & retail | 2015 |
| Better Training Solutions Ltd | Education | 2017 |
| Better VUE Landscapes Ltd | Administrative & support | 2020 |
| Better VUE Windows Ltd | Construction | 2019 |
| Bettertons UK Limited | Wholesale & retail | 2022 |
| Bevan House Limited | Real estate | 2021 |
| BEX FX Ltd | Information & communication | 2016 |
| Bexleynet Internet Services Limited | Information & communication | 2017 |
| Beyond Basics Security Limited | Other services | 2018 |
| Beyond Vennila Limited | Administrative & support | 2025 |
| Bezelchain Technologies Inc. Limited | Information & communication | 2020 |
| BF Gardens UK Limited | Administrative & support | 2026 |
| BF Source Ltd | Other services | 2019 |
| Bfvp Solutions Limited | Professional & scientific | 2016 |
| BGS (Pentian Green) Holdings Limited | Extraterritorial | 2005 |
| BH Bucks Windows Ltd | Administrative & support | 2020 |
| Bhaks Ltd | Health & social care | 2015 |
| Bhargava Associates Limited | Health & social care | 2013 |
| Bhargava Property Management Limited | Real estate | 2014 |
| Bhela Limited | Hospitality | 2023 |
| BHN Ltd | Other services | 2017 |
| Bhope Consultancy Ltd | Wholesale & retail | 2023 |
| BHP Automotive Ltd | Wholesale & retail | 2023 |
| BHP Electronics Ltd | Wholesale & retail | 2024 |
| Biba Consulting Ltd | Professional & scientific | 2025 |
| Biberetto Limited | Wholesale & retail | 2017 |
| BIC Wholesale Trade Ltd | Wholesale & retail | 2023 |
| Bickley Chartered Loss Adjusters Limited | Financial services | 2009 |
| Bicycle Tribe Limited | Wholesale & retail | 2014 |
| Bidston Hill Ltd | Construction | 2017 |
| Bieze Ltd | Wholesale & retail | 2026 |
| Biffa (Corby) Limited | Water & waste | 1996 |
| Biffa (Roxby) Limited | Extraterritorial | 1986 |
| Biffa (UK) Holdings Limited | Professional & scientific | 1996 |
| Biffa (WES) Limited | Water & waste | 1992 |
| Biffa (West Sussex) Recycling Limited | Water & waste | 2003 |
| Biffa BDR Holdings Limited | Professional & scientific | 2011 |
| Biffa BDR Limited | Other services | 2011 |
| Biffa Bidco Limited | Financial services | 2022 |
| Biffa Corporate Holdings Limited | Water & waste | 2005 |
| Biffa Cumbria Holdings Ltd | Professional & scientific | 2009 |
| Biffa Cumbria Ltd | Other services | 2009 |
| Biffa Environmental Municipal Services Limited | Water & waste | 1967 |
| Biffa Group Holdings (UK) Limited | Professional & scientific | 2000 |
| Biffa Group Limited | Professional & scientific | 2007 |
| Biffa GS (FC) Limited | Water & waste | 2003 |
| Biffa GS (M&B) Limited | Water & waste | 1974 |
| Biffa GS Environmental Limited | Water & waste | 1997 |
| Biffa GS Environmental Recycling Limited | Extraterritorial | 2003 |
| Biffa GS Holdings Limited | Water & waste | 2002 |
| Biffa GS UK Holdings Limited | Water & waste | 2003 |
| Biffa Holdco Limited | Financial services | 2022 |
| Biffa Holdings Limited | Water & waste | 1971 |
| Biffa Landfill Solutions Holdings Limited | Professional & scientific | 1990 |
| Biffa Landfill Solutions Limited | Water & waste | 1978 |
| Biffa Leicester Limited | Water & waste | 2002 |