| Breathing Buildings Limited | Manufacturing | 2006 |
| Brenchley Garage Limited | Wholesale & retail | 2003 |
| Brendan Enterprises Limited | Arts & recreation | 2001 |
| Brent Creative Design & Print Limited | Manufacturing | 2024 |
| Brewbridge Ltd | Wholesale & retail | 2026 |
| Brice Medical Ltd | Health & social care | 2025 |
| Bright Blue Two Limited | Real estate | 2017 |
| Bright Cleaning East Grinstead Limited | Administrative & support | 2021 |
| Bright Knight Media Limited | Professional & scientific | 2018 |
| Bright Nova Limited | Real estate | 2025 |
| Bright Routes Education Consultant Ltd | Education | 2024 |
| Brightmatter Solutions Limited | Information & communication | 2016 |
| Brighton Chaudhari Burger Limited | Hospitality | 2026 |
| Brighton Dental Ltd | Health & social care | 2021 |
| Brighton Noodle Bar Ltd | Hospitality | 2015 |
| Brightoncurry Ltd | Hospitality | 2022 |
| Britania Tamil School - Crawley Ltd | Health & social care | 2020 |
| Britannia Paving Ltd | Administrative & support | 2025 |
| Britbrazil Network Ltd | Arts & recreation | 2025 |
| Brits Enterprises Limited | Transport & logistics | 2023 |
| Broad Oak Court Residents Association Limited | Households | 1973 |
| Broad Walk Market Ltd | Other services | 2024 |
| Broadbridge Precision Engineering Limited | Manufacturing | 1977 |
| Broadcast Relay Service (Overseas) Limited | Extraterritorial | 1947 |
| Broadfield Barton Property Management Limited | Real estate | 1985 |
| Broadfield Land Management Limited | Real estate | 2024 |
| Broadfield Laundry Ltd | Administrative & support | 2025 |
| Broadfield Nursery Community Interest Company | Education | 2013 |
| Broadfield Park Limited | Real estate | 1989 |
| Bromford Investments Limited | Professional & scientific | 2009 |
| Bromley Business Network Limited | Other services | 2019 |
| Bromley Garden Designs Limited | Administrative & support | 2025 |
| Broncastell Limited | Health & social care | 2010 |
| Brook Court (Copthorne) Management Company Limited | Households | 2010 |
| Brookes Associates Finance Limited | Financial services | 1978 |
| Brookes Farm Surrey Limited | Extraterritorial | 2025 |
| Brookfield Day Nursery Ltd | Education | 1999 |
| Brooklands Homecare Ltd | Health & social care | 2014 |
| Bruvix Group UK Limited | Wholesale & retail | 2022 |
| Bruvix Homes Ltd | Real estate | 2022 |
| Bruvix Hospitality Ltd | Professional & scientific | 2025 |
| BST Logistics Limited | Transport & logistics | 2010 |
| BTN Beauty Ltd | Other services | 2024 |
| Buchanan Lodge Ltd | Real estate | 2020 |
| Buchu Business Services Ltd | Financial services | 2019 |
| Buck IT Solutions Ltd | Information & communication | 2025 |
| Buckeye Fire Limited | Extraterritorial | 2015 |
| Buckrest Limited | Construction | 1977 |
| Budo Kyokushinkai Ltd | Education | 2026 |
| Buhanza Enterprises Ltd | Administrative & support | 2018 |
| Build HER Space Limited | Construction | 2025 |
| Builders Nobil Ltd | Construction | 2025 |
| BUILDERS4YOU Ltd | Construction | 2017 |
| Building Care Services Ltd | Construction | 2026 |
| Building Heroes Property Services Ltd | Construction | 2020 |
| Buildtech Developments Ltd | Construction | 2016 |
| Buildux Ltd | Construction | 2022 |
| Bullbookie Ltd | Information & communication | 2025 |
| Bulldog Holidays Limited | Other services | 2016 |
| Bumble Tree Services Limited | Agriculture & fishing | 2023 |
| Bumblebee Construction Ltd | Construction | 2023 |
| Bundoc Ltd | Manufacturing | 2006 |
| Bunks Elite Services Limited | Other services | 2026 |
| Buntingford Dental Care Limited | Health & social care | 2011 |
| Burgess Hill Local Limited | Wholesale & retail | 2026 |
| Burke Maintenance Engineering Ltd | Manufacturing | 2025 |
| Burlands Tyres Limited | Extraterritorial | 2013 |
| Burns Way Property Limited | Professional & scientific | 2009 |
| Burraaq Ltd | Wholesale & retail | 2022 |
| Business Accounting Systems Ltd | Information & communication | 2026 |
| Buss Construction Ltd | Construction | 2022 |
| Busy Bees UK Services Ltd | Administrative & support | 2021 |
| Butler and HOG Limited | Hospitality | 2020 |
| Butler Meridian Limited | Professional & scientific | 2017 |
| Butterfly Pre-School Limited | Education | 2010 |
| Buxton Homes (Brrg) Limited | Real estate | 2009 |
| Buxton Homes (Naval ROW) Limited | Real estate | 2001 |
| Buxton Homes (Poplar) Limited | Real estate | 2001 |
| Buxton Homes (Shoreditch) Limited | Real estate | 2000 |
| Buxton Management Company Limited | Real estate | 1990 |
| Buxton Properties Limited | Real estate | 1988 |
| Buyuse Ltd | Information & communication | 2026 |
| Buzzz Barbers Limited | Other services | 2016 |
| Byalphafilms Limited | Information & communication | 2023 |
| Byerswood Limited | Administrative & support | 2012 |
| Bynd Rehab Ltd | Health & social care | 2023 |
| Bypablo Ltd | Wholesale & retail | 2020 |
| BYT & Co PVT Ltd | Hospitality | 2023 |
| Bytebridge Technologiesuk Ltd. | Wholesale & retail | 2023 |
| C & H Construction South East Limited | Construction | 2008 |
| C & J Charles Limited | Construction | 2023 |
| C and H Trading LP | | 2017 |
| C Foss & Sons (Surrey) Ltd | Real estate | 2015 |
| C Foss Ltd | Real estate | 2015 |
| C J S Mortgage Consultant Ltd | Financial services | 2025 |
| C Paterson Limited | Information & communication | 2015 |
| C S Carpentry Ltd | Construction | 2007 |
| C&O Crawley Homes Ltd | Real estate | 2025 |
| C&T UK Ltd | Administrative & support | 2006 |
| C. a. Bowers & Sons (Hauliers) Limited | Transport & logistics | 1978 |