| Borne Consultancy Limited | Professional & scientific | 2013 |
| Bornel Care Limited | Health & social care | 2011 |
| Bornhill Estates Limited | Real estate | 2013 |
| Boro & Co International Limited | Professional & scientific | 2016 |
| Borodescu Delivery Limited | Transport & logistics | 2026 |
| Boronica Transport Ltd | Transport & logistics | 2016 |
| Borough Electrical Engineers Services Limited | Construction | 2015 |
| Borrowed Time Records Ltd | Information & communication | 2025 |
| Borshch Electrical Limited | Extraterritorial | 2018 |
| Borshch Holdings Limited | Financial services | 2019 |
| Borshch Limited | Wholesale & retail | 1982 |
| Bortex Clothing Industry Company Limited | Wholesale & retail | 1978 |
| BOS Group T/A Business Outsourcing Solutions Limited | Wholesale & retail | 2019 |
| BOS Realisations Limited | | 1943 |
| Bosch Care Ltd | Administrative & support | 2023 |
| Bose Edutech Limited | Professional & scientific | 2020 |
| Boset 4 Enterprises Ltd | Wholesale & retail | 2020 |
| Boset 4 Limited | Health & social care | 2012 |
| BOSET4 Property Limited | Real estate | 2024 |
| Bosh Services Ltd | Construction | 2025 |
| Bosma Spinal Surgery Ltd. | Health & social care | 2011 |
| Bosmere Management Company Limited | Households | 1982 |
| Bosnian Cultural Centre - Midlands | Professional & scientific | 2003 |
| Bosnische Kulturfoerderung Limited | Administrative & support | 2011 |
| Bosonics Ltd | Information & communication | 2011 |
| Boss & Co Homes Ltd | Extraterritorial | 2010 |
| Boss Brgr Ltd | Hospitality | 2023 |
| Boss Bricks Company Limited | Real estate | 2020 |
| Boss Cleaning&Ironing Services Ltd | Administrative & support | 2018 |
| Boss Funeral EOT Limited | Professional & scientific | 2025 |
| Boss Funeral Holdings Limited | Financial services | 2016 |
| Boss Housing Contractors Ltd | Construction | 2025 |
| Boss M 1 Ltd | Real estate | 2024 |
| Boss Mart 1 Ltd | Wholesale & retail | 2024 |
| Boss Mart 8 Ltd | Wholesale & retail | 2024 |
| Boss Mart M4 Ltd | Wholesale & retail | 2025 |
| Boss Music Productions Ltd | Information & communication | 2024 |
| Boss Nutrition UK Ltd | Wholesale & retail | 2018 |
| Boss PIG Ltd | Financial services | 2016 |
| Boss Valets Ltd | Administrative & support | 2024 |
| Boss Vehicles Ltd | Other services | 2018 |
| Bosseco Ltd | Other services | 2024 |
| Bossy Media Ltd | Professional & scientific | 2022 |
| Bostan Group Limited | Financial services | 2023 |
| Bostan Holdings Limited | Professional & scientific | 2023 |
| Bostan Property Limited | Real estate | 2021 |
| Bostan Property Solutions Ltd | Real estate | 2017 |
| Bostin Crafts and Creations Ltd | Wholesale & retail | 2024 |
| Bostin Earth Ltd | Information & communication | 2024 |
| Bostin Hairpins Ltd | Manufacturing | 2019 |
| Bostin Productions Ltd | Arts & recreation | 2012 |
| Boston Clark Limited | Administrative & support | 2016 |
| Boston Clothing Company Limited | Wholesale & retail | 2008 |
| Bostrom Property LLP | | 2008 |
| Bosworth Food Stores Ltd | Wholesale & retail | 2018 |
| Bosworth Investments Limited | Real estate | 2022 |
| Bosworth Learning & Development Limited | Professional & scientific | 2011 |
| Bosworth Newco 1 Limited | Financial services | 2025 |
| Bosworth Newco 2 Limited | Financial services | 2025 |
| Bosworth News Ltd | Wholesale & retail | 2015 |
| Bosworth Stores Limited | Wholesale & retail | 2013 |
| Botan&Co Limited | Real estate | 2021 |
| Botanic BT7 Limited | Hospitality | 2024 |
| Botanical ENG Limited | Health & social care | 2016 |
| Botanik Ecosupply Ltd | Professional & scientific | 2024 |
| Botea Primeflow Transport Limited | Transport & logistics | 2026 |
| Boteno Ltd | Wholesale & retail | 2024 |
| Botham Coaching Services Ltd. | Professional & scientific | 2022 |
| Botteville Gardens Company Limited | Administrative & support | 2015 |
| Botteville Properties Ltd | Real estate | 2022 |
| Botvistaa Ltd | Professional & scientific | 2025 |
| Bouba UK Limited | Wholesale & retail | 2025 |
| Bouchon Wine Limited | Wholesale & retail | 2013 |
| Bouden Travel Ltd | Transport & logistics | 2013 |
| Boudica Entertainment Limited | Information & communication | 2019 |
| Boughton Enterprises Limited | Extraterritorial | 2004 |
| Boughton Holdings | Extraterritorial | 2000 |
| Bougie Boujee Ltd | Wholesale & retail | 2025 |
| Boujee Beauty Studios Limited | Real estate | 2024 |
| Boujnih Ltd | Transport & logistics | 2024 |
| Boulderecho Creations Ltd | Wholesale & retail | 2025 |
| Boulevard Flowers Ltd | Wholesale & retail | 2020 |
| Boulevard Management Company (Barnt Green) Limited | Households | 1996 |
| Boultbee Business Units (Nechells) Limited | Real estate | 2006 |
| Boulton Building Services Ltd | Construction | 2026 |
| Bounce (UK) Ltd | Real estate | 2014 |
| Bounce Brigade Ltd | Administrative & support | 2024 |
| Bounce Fitness Limited | Arts & recreation | 2015 |
| Bounce Trade Limited | Information & communication | 2021 |
| Boundary Breakers Cricket Club CIC | Health & social care | 2026 |
| Boundary Road Convenience Stores Limited | Wholesale & retail | 2013 |
| Boundary Sports Limited | Wholesale & retail | 2023 |
| Boundata Limited | | 1986 |
| Boundless WE Limited | Arts & recreation | 2024 |
| Bounties Plus Ltd | Wholesale & retail | 2025 |
| Bourlet Consultancy Limited | Professional & scientific | 2026 |
| Bourn Beautiful Naturals Ltd | Manufacturing | 2020 |
| Bourn London Ltd | Wholesale & retail | 2013 |
| Bournbrook Manor Limited | Health & social care | 2016 |
| Bournbrook Secret Woods Ltd | Real estate | 2022 |