| Barons Court Management Co. Limited | Households | 1987 |
| Barons Croft (Bournemouth) Management Company Limited | Households | 1996 |
| Baronsmede Residents Management Company Limited | Households | 1970 |
| Barr Consulting Limited | Professional & scientific | 1997 |
| Barr Invest Limited | Hospitality | 2025 |
| Barr&Co Ltd | Arts & recreation | 2024 |
| Barratt Property Ltd | Real estate | 2022 |
| Barres Investments Ltd | Financial services | 2020 |
| Barrett Building Group Ltd | Construction | 2019 |
| Barril Best Pizza Ltd | Hospitality | 2025 |
| Barrowfield Hotel Limited | Hospitality | 2006 |
| Bart Agri Limited | Wholesale & retail | 2021 |
| Bart BRZ Ltd | Other services | 2019 |
| Bartlett 61 Limited | Extraterritorial | 2014 |
| Bartlett Estates Limited | Real estate | 2016 |
| Bartlett Properties Limited | Real estate | 2000 |
| Barton Civils Group Ltd | Real estate | 2023 |
| Barton Developments Ltd | Real estate | 2025 |
| Barton Green Flats Management Company Limited | Households | 1992 |
| Barton Search Ltd | Administrative & support | 2021 |
| BARZAN2003 Ltd | Other services | 2019 |
| Base & Sazon Ltd | Hospitality | 2025 |
| Basically Bathrooms Limited | Professional & scientific | 2003 |
| Baskt Limited | Wholesale & retail | 2026 |
| Bastion Militaria Ltd | Wholesale & retail | 2024 |
| Batch Bournemouth Ltd | Manufacturing | 2025 |
| Batch Kitchen Limited | Manufacturing | 2025 |
| Bateman Wellbeing Limited | Health & social care | 2021 |
| Bath Hill Court (Bournemouth) Management Company Limited | Households | 1977 |
| Bath Repair and RE Enamelling Bournemouth Limited | Other services | 2026 |
| Bathroom Elegance (Poole) Limited | Wholesale & retail | 2006 |
| Bathrooms of Bournemouth Limited | Extraterritorial | 2008 |
| Bathwick Lodge Limited | Households | 1992 |
| Bauen Decor Limited | Construction | 2023 |
| Bauhinia Properties Ltd | Real estate | 2020 |
| Bay Architecture Limited | Professional & scientific | 2019 |
| Bay Crest Owners Limited | Households | 2020 |
| Bay View Gardens Freehold Limited | Households | 2012 |
| Bay View Rise Management Co. Limited | Households | 1986 |
| BAY2BAY Limited | Construction | 2006 |
| Bayat Cleaning Service Ltd | Administrative & support | 2026 |
| Bayley Assets Limited | Financial services | 2020 |
| Bayline Property Group Ltd | Households | 2025 |
| Bayside (2003) Limited | Real estate | 2003 |
| Bayside HR Ltd | Professional & scientific | 2021 |
| Baytree Plastering Limited | Construction | 2019 |
| Bayview (Westcliff) Limited | Households | 2008 |
| Baywood Aesthetics Limited | Health & social care | 2024 |
| Bazco Limited | Construction | 2000 |
| Bbbsd Limited | Wholesale & retail | 2022 |
| BBD Group Ltd | Financial services | 2018 |
| BBL Gym Southampton Ltd | Arts & recreation | 2024 |
| BBM Canal Road Freehold Ltd | Households | 2024 |
| BBM Music Ltd | Wholesale & retail | 2020 |
| BBS Mani Barber Ltd | Other services | 2026 |
| BBV Ltd | Hospitality | 2022 |
| BBX Carbon Offset Ltd | Wholesale & retail | 2018 |
| BBX Europe Sales Ltd | Professional & scientific | 2018 |
| BBX Exchange Ltd | Administrative & support | 2008 |
| BBX Management Limited | Administrative & support | 2014 |
| Bcas Global (UK) Ltd | Professional & scientific | 2003 |
| Bcas Properties Ltd | Real estate | 2024 |
| BCJ Farriery Ltd | Manufacturing | 2024 |
| BCJ Gardens Ltd | Professional & scientific | 2024 |
| BCK Designs Ltd | Manufacturing | 2017 |
| Bclinical Ltd | Other services | 2010 |
| BCP Construction Ltd | Construction | 2025 |
| BCP Electrical & Renewables Ltd | Construction | 2023 |
| BCP Holdings Limited | Real estate | 2021 |
| BCP House Clearance Ltd | Water & waste | 2025 |
| BCP Nepalese Community-Dorset-Uk Ltd | Health & social care | 2022 |
| BCP Travel Ltd | Transport & logistics | 2024 |
| Bcp@Home Ltd | Real estate | 2024 |
| BCS Scaffolding Limited | Construction | 2017 |
| BCV UK Consultants Ltd | Professional & scientific | 2022 |
| BD Distribution Europe Ltd | Wholesale & retail | 2018 |
| Bdbt Property Limited | Real estate | 2023 |
| Bdfvans Ltd | Construction | 2025 |
| BDH Investments Limited | Real estate | 2017 |
| Bdhd Consultancy Limited | Professional & scientific | 2016 |
| BE Hair Salon Ltd | Other services | 2024 |
| BE Willis Partnership Limited | Professional & scientific | 2008 |
| BE Yourself Ltd | Health & social care | 2015 |
| BE24 Limited | Construction | 2023 |
| BE25 Limited | Construction | 2024 |
| Bea...Beauty&Health Ltd | Wholesale & retail | 2020 |
| Beach House (Mudeford) Limited | Hospitality | 2013 |
| Beach Life Commercial Limited | Real estate | 2026 |
| Beach Life Construction Ltd | Construction | 2024 |
| Beach Life Developments Ltd | Construction | 2023 |
| Beach Life Parent Company Limited | Financial services | 2026 |
| Beachbumsup Ltd | Wholesale & retail | 2021 |
| Beachland Properties (Glenville Road ) Ltd | Real estate | 2007 |
| Beachwalk (Poole) Management Company Limited | Households | 1991 |
| Beachwalk Management Company Limited | Real estate | 1989 |
| Beacon Management (Branksome Park) Limited | Households | 2000 |
| Beacon Trustees Limited | Extraterritorial | 2005 |
| Beacontree Properties Limited | Real estate | 2016 |
| Beaf Arts Company Ltd | Arts & recreation | 2017 |
| Beagle Art Ltd | Arts & recreation | 2025 |