| BEN Humphrey Plumbing Ltd | Construction | 2015 |
| Benford Accountancy Limited | Professional & scientific | 2012 |
| Bennett Autos Ltd | Wholesale & retail | 2013 |
| Bennett Bros Limited | Wholesale & retail | 2001 |
| Berrow Developments Ltd | Construction | 2025 |
| Bespoke Accounting 2018 Limited | Professional & scientific | 2019 |
| Bespoke Office Solutions & Services Ltd | Administrative & support | 2017 |
| Bespoke Relocation Group Ltd | Transport & logistics | 2024 |
| Bespoke YOU Limited | Other services | 2019 |
| Bevision Limited | Information & communication | 2012 |
| Beyond the Sky Nutrition Limited | Other services | 2024 |
| BFL2 Media LLP | | 2021 |
| Bgnk Ltd | Professional & scientific | 2023 |
| Bhatt Group Ltd | Information & communication | 2023 |
| Bickers Insurance Services Limited | Financial services | 2013 |
| Big D Enterprises Limited | Financial services | 2003 |
| Big Foot Property Ltd | Real estate | 2017 |
| Big Red Horn Services Ltd | Real estate | 2020 |
| Bigchurch.Co Limited | Administrative & support | 2026 |
| Biggs Build Limited | Construction | 2021 |
| Bill Dodd Computer Systems Limited | Information & communication | 2014 |
| Bilton Fields Homes Limited | Construction | 2019 |
| Biohazard Candy Ltd | Manufacturing | 2021 |
| Biolight Limited | Construction | 2024 |
| Bioprobe Limited | Professional & scientific | 2014 |
| Bird and SON Property Services Limited | Construction | 2024 |
| Birmingham Lane Ltd | Arts & recreation | 2013 |
| Bite Collective Ltd | Professional & scientific | 2021 |
| Bitpixstore Limited | Wholesale & retail | 2024 |
| BK Lettings Ltd | Real estate | 2023 |
| Blackfriars Enterprises Limited | Information & communication | 1988 |
| Blackman Property Ltd. | Construction | 2021 |
| Blacxfoods Ltd | Hospitality | 2026 |
| Blended Salon Ltd | Other services | 2025 |
| Bliss Contracts Limited | Construction | 2025 |
| Bloomsbury Enterprise Limited | Real estate | 2021 |
| Bluebell Gate (East Grinstead) Management Company Limited | Households | 2012 |
| Blueflame Digital Ltd | Information & communication | 1999 |
| Blueprint Youth UK Ltd | Education | 2011 |
| Bluesky Business Centres Ltd | Real estate | 2019 |
| Bluesky Hove Ltd | Real estate | 2014 |
| BMC Building Management Services Ltd | Professional & scientific | 2024 |
| BMM Consulting Services Limited | Professional & scientific | 2017 |
| Bmpr Ltd | Professional & scientific | 2018 |
| Board AF Ltd | Wholesale & retail | 2021 |
| BOAT2BOAT Ltd | Extraterritorial | 2024 |
| Body Sense (Beauty) Limited | Other services | 2019 |
| Boiled Web Limited | Information & communication | 2015 |
| Bolder Creative Limited | Professional & scientific | 2022 |
| Boldertv Ltd | Administrative & support | 2007 |
| Bolland Holdings Ltd | Financial services | 2022 |
| Bolo Athletics Apparel Ltd | Wholesale & retail | 2025 |
| Bonarima London Ltd | Manufacturing | 2021 |
| Bonga Cargo Service Limited | Transport & logistics | 2013 |
| Booze on the Go Ltd | Wholesale & retail | 2019 |
| Botting & Co (Auditors) Limited | Professional & scientific | 2017 |
| Boughton Lodge Water Sports Club Limited | Arts & recreation | 1987 |
| Bounce-Mania Limited | Arts & recreation | 2013 |
| Bowls Club Lawn Care Ltd | Real estate | 2026 |
| Boxed Holdings Limited | Financial services | 2018 |
| Boyal Fish Ltd | Hospitality | 2026 |
| BR Commodities Limited | Manufacturing | 2025 |
| Bradstone Developments Ltd | Construction | 2022 |
| Brampton Court (Sussex) Limited | Real estate | 1969 |
| Brandme Workwear Ltd | Manufacturing | 2026 |
| Brave New Words Limited | Professional & scientific | 2013 |
| Breakthrough Communications & Strategies Limited | Information & communication | 2019 |
| Brennan and Chatterton Estates Limited | Real estate | 2019 |
| Brennan and Chatterton Lettings Limited | Real estate | 2021 |
| Brennan and Chatterton Sussex Limited | Real estate | 2026 |
| Brevant Capital Ltd | Administrative & support | 2020 |
| Brian Elstone, Surveying Services Limited | Professional & scientific | 2009 |
| Bridgeapex Property Management Limited | Real estate | 2006 |
| Briggs Roofing and General Building Ltd | Construction | 2022 |
| Bright on Beauty Limited | Other services | 2010 |
| Brightlights Homeschool Ltd | Education | 2014 |
| Brighton & Hove Stays LLP | | 2023 |
| Brighton and Hove City FC Ltd | Arts & recreation | 2013 |
| Brighton Global Movement Ltd | Transport & logistics | 2024 |
| Brill Ideas Limited | Administrative & support | 2012 |
| Brinks MAT Holdings Limited | Real estate | 2024 |
| Brinson Investments Limited | Professional & scientific | 2023 |
| Britassist Ltd | Administrative & support | 2007 |
| Broadstrand (Rustington) Limited | Households | 1997 |
| Brockhampton Land Company,Limited | Real estate | 1933 |
| Brooklands Residents Association Limited | Households | 1996 |
| Brookside Business Park Management Limited | Households | 2006 |
| Broomfield Construction Limited | Construction | 2018 |
| Broski Record Label Ltd | Wholesale & retail | 2025 |
| Brown Loop Limited | Extraterritorial | 2021 |
| BSM Advisers Limited | Professional & scientific | 2012 |
| BTR Direct Ltd | Wholesale & retail | 2006 |
| Bubbles Washeteria Limited | Administrative & support | 2017 |
| Buchanan (Equipment) Limited | Wholesale & retail | 1995 |
| Building Supplies Direct Ltd | Wholesale & retail | 2013 |
| Bunce Consulting Ltd | Administrative & support | 2008 |
| Burdsall Engineering Ltd | Information & communication | 2022 |
| Burgundy Financial Limited | Professional & scientific | 2018 |
| Burleigh Court (Worthing) RTM Company Limited | Administrative & support | 2019 |
| Burtcher Way Ltd | Information & communication | 2021 |