| Blue Strawberry AI Ltd | Information & communication | 2019 |
| Blue Strawberry Ltd | Information & communication | 2024 |
| Blue Tea House Ltd | Hospitality | 2022 |
| Bluebeach Solutions Ltd | Administrative & support | 2010 |
| Bluebell and Eagle Publishing Ltd | Information & communication | 2021 |
| Bluebell Maintenance and Landscaping Limited | Administrative & support | 2023 |
| Bluebell Medicare Limited | Professional & scientific | 2010 |
| Bluebell Oak Estates Ltd | Real estate | 2025 |
| Bluebell Woods Park Homes Limited | Hospitality | 2019 |
| Bluegreen Oasis Ltd | Financial services | 2022 |
| Bluekat Solutions Limited | Information & communication | 2015 |
| Blueline Travel Kent Ltd | Transport & logistics | 2025 |
| Blxd Productions Ltd | Arts & recreation | 2025 |
| BMS Finance AB Limited | Financial services | 2006 |
| Bnkc Medicals Limited | Health & social care | 2026 |
| BNL Transport Ltd | Transport & logistics | 2022 |
| Boardwave Ltd | Information & communication | 2022 |
| Boarman Limited | Construction | 2022 |
| Boat House Properties (Iwade) Limited | Real estate | 2016 |
| Bobaa & Co Ltd | Hospitality | 2023 |
| Bocobay Holdings Ltd | Financial services | 2021 |
| Bocobay Ltd | Professional & scientific | 2022 |
| Bogan Property (Kent) Ltd | Real estate | 2023 |
| Boktor Ltd | Administrative & support | 2023 |
| BON Enfant Consulting Limited | Professional & scientific | 2021 |
| Bona OMI Productions Ltd | Information & communication | 2023 |
| Bonev Motors Ltd | Transport & logistics | 2024 |
| Bonnets 2 Boots Limited | Other services | 2019 |
| Bonsai Properties Ltd | Real estate | 2019 |
| Books of Africa Ltd | Information & communication | 2008 |
| Books to Africa International | Education | 2013 |
| Boom Fitness Ltd | Arts & recreation | 2014 |
| Boostex Ltd | Wholesale & retail | 2025 |
| Booxenbir Ltd | Professional & scientific | 2021 |
| Boo’S Kitchen Ltd | Hospitality | 2026 |
| Borden Village PRE School Limited | Education | 2008 |
| Bordercross Health Ltd | Information & communication | 2023 |
| Borderflight Properties Ltd | Extraterritorial | 2013 |
| Born and Braised Limited | Hospitality | 2025 |
| Borough Green Sand Pits Limited | Mining & quarrying | 1956 |
| Boss Plant Hire Limited | Construction | 2000 |
| Bossingham Preschool Ltd | Education | 2013 |
| Botting Farms Limited | Financial services | 2019 |
| Bourne Design Studio Limited | Professional & scientific | 2015 |
| Bourne Drive Ltd | Households | 2018 |
| Bourne Land & Planning Studio Limited | Construction | 2022 |
| Bourne Park Capital Limited | Professional & scientific | 1999 |
| Bourne Performance Limited | Wholesale & retail | 2005 |
| Bourne Property & Letting Ltd | Real estate | 2024 |
| Bourne Studio Limited | Professional & scientific | 2022 |
| Bourne to Garden Limited | Administrative & support | 2015 |
| Boutiq Bullz Limited | Agriculture & fishing | 2016 |
| Bovan Creek Ltd | Transport & logistics | 2021 |
| BOW WOW Meow Limited | Wholesale & retail | 2009 |
| Bowyers Field Developments Limited | Real estate | 2015 |
| Bowzell Limited | Extraterritorial | 1941 |
| Bowzell Plant Limited | Extraterritorial | 1954 |
| Box Sash Window Repair Ltd | Manufacturing | 2018 |
| Brabourne Films Limited | Extraterritorial | 1956 |
| Bradley & Partners Canterbury Ltd | Health & social care | 2023 |
| Bradley & Partners Limited | Health & social care | 2013 |
| Bradyll Ltd | Construction | 2020 |
| Braintree Express Ltd | Wholesale & retail | 2025 |
| Brakepoint Limited | Arts & recreation | 2025 |
| Brakepoint Wincheap Limited | Arts & recreation | 2025 |
| Brambles MOT Centre Limited | Wholesale & retail | 2008 |
| Brambles Property Development Limited | Real estate | 2002 |
| Bramling Construction Limited | Construction | 2008 |
| Brand New English Limited | Education | 2014 |
| Brandspire Digital Limited | Professional & scientific | 2023 |
| Brankley Consulting Limited | Professional & scientific | 2010 |
| Brave and Lost Ltd | Arts & recreation | 2018 |
| Bravepoint Solutions Limited | Information & communication | 2025 |
| Braveworld Limited | Information & communication | 2021 |
| Braypost Limited | Manufacturing | 1992 |
| Breach Lane Dog Field Ltd | Other services | 2024 |
| Bread&Cheese Ltd | Hospitality | 2021 |
| Breakthrough Consulting Limited | Professional & scientific | 2005 |
| Bredar Properties Limited | Real estate | 2009 |
| Brendan Power Limited | Arts & recreation | 2017 |
| Brett Aggregates Limited | Mining & quarrying | 1936 |
| Brett Asphalt Limited | Mining & quarrying | 1962 |
| Brett Concrete Limited | Manufacturing | 1959 |
| Brett Construction Limited | Professional & scientific | 2007 |
| Brett Developments Limited | Manufacturing | 1958 |
| Brett Fairlop Limited | Mining & quarrying | 1997 |
| Brett Group Holdings Limited | Professional & scientific | 2022 |
| Brett Group Properties Limited | Real estate | 2022 |
| Brett Landscaping Limited | Mining & quarrying | 1938 |
| Brett Marine Aggregates Limited | Mining & quarrying | 1965 |
| Brett Milton Limited | Administrative & support | 2004 |
| Brett Nova UK Limited | Wholesale & retail | 2000 |
| Brett Paving Limited | Mining & quarrying | 1959 |
| Brett Pension Trustee Limited | Financial services | 2011 |
| Brett Trading Limited | Professional & scientific | 1980 |
| Bretts of Canterbury Ltd | Real estate | 2023 |
| Brian R W Murray Limited | Construction | 2018 |
| Brian Roberts Loft Conversions Limited | Construction | 2003 |
| Bridge Dental Practice (Canterbury) Limited | Health & social care | 2021 |
| Bridge Regulatory Consulting Limited | Professional & scientific | 2011 |