| BEN Bird Design Limited | Arts & recreation | 2023 |
| BEN Fletcher Public Relations Ltd | Professional & scientific | 2018 |
| BEN Karter Music Limited | Professional & scientific | 2015 |
| BEN Thorne Ltd | Professional & scientific | 2019 |
| Ben&Jack Studio Ltd | Information & communication | 2019 |
| Benchmark Fitness Limited | Arts & recreation | 2016 |
| Bencris Services Limited | Health & social care | 2013 |
| Beneebs Limited | Information & communication | 2017 |
| Bengal Commodities Limited | Financial services | 2018 |
| Benjamiinc Ltd | Arts & recreation | 2023 |
| Bennsminiservicing Limited | Manufacturing | 2024 |
| Benson Printworks Limited | Professional & scientific | 2002 |
| Berkeley Business Park Management Company Limited | Real estate | 1988 |
| Berkeley Car Company Limited | Wholesale & retail | 2007 |
| Berkeley Car Garage Limited | Wholesale & retail | 2014 |
| Berkeley Lettings Limited | Transport & logistics | 2019 |
| Berkley Precision Engineering Ltd | Construction | 2005 |
| Berks Real Estate Limited | Real estate | 2026 |
| Berkshire Aesthetics (Services) Limited | Health & social care | 2019 |
| Berkshire Aesthetics Ltd | Health & social care | 2012 |
| Berkshire Auto Specialists Limited | Wholesale & retail | 2026 |
| Berkshire Boats Ltd | Other services | 2011 |
| Berkshire Bookkeeping Services Limited | Professional & scientific | 2012 |
| Berkshire Childrens Homes Ltd | Health & social care | 2025 |
| Berkshire EYE Clinic Ltd | Health & social care | 2011 |
| Berkshire Group Pharma Ltd | Wholesale & retail | 2026 |
| Berkshire Grove Hospital Ltd | Health & social care | 2022 |
| Berkshire Hand Surgery Limited | Extraterritorial | 2011 |
| Berkshire Health Group Limited | Health & social care | 2023 |
| Berkshire Health Limited | Health & social care | 2010 |
| Berkshire Home Improvements Limited | Construction | 2009 |
| Berkshire Investment Management Ltd | Administrative & support | 2015 |
| Berkshire IT Solutions Limited | Information & communication | 2023 |
| Berkshire Mortgage Services Limited | | 1985 |
| Berkshire Oakmont Limited | Hospitality | 2017 |
| Berkshire Property Buyer Ltd | Real estate | 2021 |
| Berkshire Rare Books Ltd | Wholesale & retail | 2021 |
| Berkshire Riverside Autos Limited | Wholesale & retail | 2022 |
| Berkshire Sports and Prestige Limited | Wholesale & retail | 2016 |
| Berkshire Translation Bureau (BTB) Ltd | Professional & scientific | 2022 |
| Berkshire Vale Limited | Real estate | 2024 |
| Berkshire Wholesale Supplies (2002) Ltd | Wholesale & retail | 2001 |
| Berkshiresupplies Limited | Wholesale & retail | 2025 |
| Berookie Limited | Wholesale & retail | 2022 |
| Bespoke Automation Systems Limited | Information & communication | 2026 |
| Bespoke Concierge Services Limited | Other services | 2019 |
| Best Practice Publishing Limited | Information & communication | 1994 |
| BEST-PLACE4U Ltd | Wholesale & retail | 2018 |
| Bestmmm Ltd | Professional & scientific | 2013 |
| Bestpracticebox Limited | Information & communication | 2019 |
| Beta Cargo Solutions Ltd | Transport & logistics | 2023 |
| Bethel Care Home.Co.Uk Ltd | Health & social care | 2018 |
| Betner Consultancy Limited | Professional & scientific | 2021 |
| Better Boards Limited | Professional & scientific | 2014 |
| Better Health Plus Ltd | Health & social care | 2020 |
| Bexley Heating Services Ltd | Construction | 2010 |
| Bexo Ltd | Information & communication | 2012 |
| Beyond Borders IT Services Limited | Information & communication | 2023 |
| Beyond Medical Aesthetics Limited | Wholesale & retail | 2017 |
| Beyond Zero Ventures Ltd | Professional & scientific | 2023 |
| Beyondcart Ltd | Wholesale & retail | 2024 |
| BG Advisory Partners Limited | Professional & scientific | 2019 |
| Bgjg Limited | Professional & scientific | 2016 |
| Bgmj Developments Limited | Construction | 2024 |
| BGP Trade Ltd. | Manufacturing | 2013 |
| Bhakti Yoga Ltd | Other services | 2025 |
| Bhatnagar Estate Ltd | Real estate | 2020 |
| Bhrt Ltd | Health & social care | 2018 |
| BIA Cycling Limited | Arts & recreation | 2016 |
| Big Boxes Limited | Real estate | 2023 |
| Big Bull Bags Limited | Professional & scientific | 2007 |
| Big Dog Maidenhead Limited | Wholesale & retail | 2021 |
| Big Finish Creative (UK) Limited | Information & communication | 2019 |
| Big Finish Distribution Limited | Wholesale & retail | 2024 |
| Big Finish Drama Limited | Arts & recreation | 2025 |
| Big Finish Entertainment Limited | Arts & recreation | 2014 |
| Big Finish Holdings (UK) Limited | Extraterritorial | 2019 |
| Big Finish Media Group Limited | Arts & recreation | 2015 |
| Big Finish Merchandise Limited | Arts & recreation | 2020 |
| Big Finish Productions Limited | Wholesale & retail | 1996 |
| Big Finish Theatre Limited | Arts & recreation | 2015 |
| Big Shot Basketball Ltd | Arts & recreation | 2023 |
| Big Sky Events Ltd | Administrative & support | 2021 |
| Big Splash Productions Limited | Information & communication | 2003 |
| Big Stitch Events Limited | Administrative & support | 2022 |
| Big Wipes Limited | Professional & scientific | 2007 |
| Bigfrith Investments | Financial services | 2014 |
| Bignix Consulting Limited | Information & communication | 2018 |
| Bigpie Recruitment Ltd | Professional & scientific | 2019 |
| Bigsoft Limited | Information & communication | 2000 |
| Bijou Wedding Venues Limited | Administrative & support | 2008 |
| Bilinguasing Limited | Education | 2014 |
| Billybob Design Limited | Information & communication | 2012 |
| Binalytics Limited | Information & communication | 2014 |
| Binfield Renewable Solutions Limited | Construction | 2011 |
| Biocura Solutions Ltd | Information & communication | 2026 |
| Biogen Idec Limited | Wholesale & retail | 1980 |
| Biogen Idec Research Limited | Professional & scientific | 2011 |
| Biomed Global Service PVT Ltd | Professional & scientific | 2021 |
| Biotrax Private Limited | Wholesale & retail | 2025 |