| Buckingham Mansions (Bournemouth) Limited | Households | 1959 |
| Buckingham Mansions Freehold Limited | Households | 2010 |
| Buckley Property Ventures Ltd | Real estate | 2026 |
| Buco Group Ltd | Hospitality | 2026 |
| Bueno Gelato Limited | Wholesale & retail | 2025 |
| Build Right (Construction Services) Ltd | Construction | 2015 |
| BUILD2GETHER Ltd | Professional & scientific | 2011 |
| Builderbest Ltd | Construction | 2024 |
| Building & Construction City Limited | Hospitality | 2013 |
| Building and Plastering Excellence Limited | Construction | 2026 |
| Building Better Businesses Ltd | Professional & scientific | 2022 |
| Building Options Limited | Construction | 2012 |
| Building Supply Solutions Limited | Construction | 2015 |
| Building Ventilation Solutions Ltd | Construction | 2020 |
| Buildsmiths (Dorset) Ltd | Construction | 2022 |
| BUK Travel Ltd | Extraterritorial | 2024 |
| Bukmedia Limited | Professional & scientific | 2012 |
| Bukshimer Limited | Health & social care | 2024 |
| Bulk Bros Ltd | Manufacturing | 2025 |
| Bullock & Lees Limited | Real estate | 2003 |
| Bullock and Lees (Wareham) Limited | Real estate | 2008 |
| Bulpitt Crocker Taxation Ltd | Professional & scientific | 2003 |
| Bumps & Scuffs Limited | Wholesale & retail | 2011 |
| Bunches of Limited | Wholesale & retail | 2018 |
| Bunches of Westbourne (Flowers) Ltd | Wholesale & retail | 2020 |
| Bunda Collection Ltd | Wholesale & retail | 2025 |
| Bundo Ltd | Administrative & support | 2021 |
| Bunnyfoot Ltd | Information & communication | 2000 |
| Bunsik-Uk Ltd | Hospitality | 2026 |
| Burbs Kitchen Limited | Hospitality | 2020 |
| Bure Park (1990) Limited | Households | 1989 |
| Burford Court Limited | Households | 2002 |
| Burford Court(Bournemouth)Limited | Households | 1963 |
| Burger Box 213 Ltd | Hospitality | 2025 |
| Burger Club Ltd | Wholesale & retail | 2018 |
| Burgerss Limited | Hospitality | 2025 |
| Burgerz Ltd | Hospitality | 2025 |
| Burgess & LEE Limited | Financial services | 1993 |
| Burgis Building Services Limited | Construction | 2009 |
| Burgshake Restaurants Bournemouth Ltd | Hospitality | 2023 |
| Burlevazon Ltd | Wholesale & retail | 2024 |
| Burley Grange (Management) Limited | Real estate | 1958 |
| Burley Road Management Company Limited | Real estate | 1973 |
| Burlington Mansions Freehold Limited | Households | 2014 |
| Burnaby Court Freehold Limited | Households | 2014 |
| Burnaby House (Management) Company Limited | Households | 2005 |
| Burnaby Road RTM Company Limited | Real estate | 2006 |
| Burnell & Rankin Limited | Professional & scientific | 2016 |
| Burnett Maintenance Ltd | Wholesale & retail | 2023 |
| Burnham Lodge Property Management Limited | Households | 2014 |
| Burns Property Management & Lettings 2 Limited | Households | 2023 |
| Burns Property Management & Lettings Limited | Households | 1995 |
| Burp! Limited | Hospitality | 2004 |
| Burr Coffee Limited | Manufacturing | 2021 |
| Burtley Court Owners Ltd | Households | 2003 |
| Burton Hall Management Company and Residents Association Limited | Households | 1994 |
| Burwin Estates Limited | Financial services | 2025 |
| Burwin Investments Limited | Real estate | 1947 |
| Burwin Residential Investments Limited | Financial services | 2025 |
| Bushbaby Commercial Ltd | Real estate | 2025 |
| Bushbaby Property Limited | Real estate | 2024 |
| Bushika 1 Ltd | Hospitality | 2025 |
| Business Apps London Ltd | Information & communication | 2010 |
| Business Gurus Consultancy Ltd | Information & communication | 2025 |
| Business Systems Initiatives Limited | Information & communication | 1997 |
| Busters Mobile Garage Ltd | Wholesale & retail | 2025 |
| Busy Bees Childminding Ltd | Health & social care | 2025 |
| Butterfly Nails & Aesthetics Ltd | Other services | 2025 |
| Bvspc Limited | Construction | 2024 |
| Bvsystems Ltd | Administrative & support | 2019 |
| BW Group Holdings Limited | Financial services | 2022 |
| BWC South Limited | Manufacturing | 2017 |
| BY Anya Limited | Wholesale & retail | 2024 |
| BY the Sea Aesthetics Limited | Other services | 2022 |
| Byco Flat Management (Ferndown) Limited | Households | 1975 |
| Byound Limited | Wholesale & retail | 2025 |
| Byron House (Freehold) Limited | Real estate | 2020 |
| Bytecraft Systems Ltd | Wholesale & retail | 2026 |
| BZW Ltd | Real estate | 2018 |
| C & CB Hotels Limited | Hospitality | 1996 |
| C & M Bricklaying Limited | Construction | 2001 |
| C & S Rubbish Removals Limited | Transport & logistics | 2021 |
| C Addis Consulting Limited | Other services | 2024 |
| C and H 1921 Limited | Real estate | 2017 |
| C B Brasserie Limited | Hospitality | 2010 |
| C C Agency Services Limited | Professional & scientific | 2021 |
| C Costa Electrical Limited | Construction | 2022 |
| C Foster Holdings Ltd | Real estate | 2021 |
| C J I Clothing Limited | Wholesale & retail | 2011 |
| C K Projects Limited | Construction | 2023 |
| C L C Solutions Limited | Professional & scientific | 2007 |
| C L Davison Management Consultancy Ltd | Administrative & support | 2018 |
| C Lovell Limited | Other services | 2018 |
| C P Health and Safety Services Limited | Administrative & support | 2013 |
| C T R Services Limited | Information & communication | 2006 |
| C&M Clinic - Aesthetics and Medical Ltd | Other services | 2015 |
| C&P Barnes Limited | Real estate | 2025 |
| C&S Group Management Ltd | Hospitality | 2019 |
| C&S Property Associates Limited | Real estate | 2021 |
| C&V Bright Services Ltd | Construction | 2013 |