| Borg Timber House East Midlands Limited | Construction | 2016 |
| Borley Consulting Limited | Professional & scientific | 2020 |
| Born Law Limited | Professional & scientific | 2019 |
| Born Properties Limited | Real estate | 2023 |
| Borne Events Ltd | Arts & recreation | 2023 |
| Boroughbridge Genius Ltd | Wholesale & retail | 2015 |
| Borsara Smiles Limited | Health & social care | 2023 |
| Bortell Holdings Limited | Professional & scientific | 2013 |
| Borto Limited | Professional & scientific | 2018 |
| BOS Transport Ltd | Transport & logistics | 2026 |
| Bosdip P S Limited | Construction | 2010 |
| Boss Autosport Ltd | Wholesale & retail | 2023 |
| Boss Cuts Grimsby Ltd | Other services | 2023 |
| Boss Holdings (Leicester) Limited | Financial services | 2021 |
| Boss Mart 6 Ltd | Wholesale & retail | 2025 |
| Boss Properties (Leicester) Limited | Extraterritorial | 2021 |
| Bossie Ltd | Information & communication | 2025 |
| Bossnya Ltd | Transport & logistics | 2023 |
| Bossy Clothing Ltd | Wholesale & retail | 2014 |
| Bostall Care Limited | Real estate | 2013 |
| Bostall Contracts Ltd | Construction | 2019 |
| Bostall Developments Limited | Construction | 2013 |
| Bostall Estates Limited | Construction | 1998 |
| Bostall Group Limited | Financial services | 2019 |
| Bostall Property Trading Limited | Real estate | 2013 |
| Boston & Black Limited | Real estate | 2012 |
| Boston Commercial Ltd | Wholesale & retail | 2017 |
| Boston Derby Ltd | Wholesale & retail | 2025 |
| Boston Dyers Limited | Manufacturing | 1984 |
| Boston New Homes Limited | Construction | 2022 |
| Bosworth Children's Care Ltd | Health & social care | 2025 |
| Bosworth Lakeside Lodges Limited | Hospitality | 2021 |
| Bosworth Lakeside Rentals Limited | Hospitality | 2021 |
| Bosworth Lakeside Retreat Ltd | Health & social care | 2025 |
| Bosworth Properties (Birmingham) Ltd | Real estate | 2017 |
| Bosworth Properties (Leicester) Limited | Construction | 2007 |
| Bosworth Properties (New Homes) Ltd | Construction | 2014 |
| Bosworth Properties Limited | Real estate | 1997 |
| Bosworth Wealth Management Limited | Financial services | 2018 |
| Bott Handmade Sofas Limited | Manufacturing | 2014 |
| Bottle Butler Limited | Wholesale & retail | 2012 |
| Bottle Kiln Holdings Ltd | Professional & scientific | 2022 |
| Bottle Kiln Ltd | Construction | 2023 |
| Bouaaoud Trading Ltd | Transport & logistics | 2021 |
| Bougal Ltd | Wholesale & retail | 2025 |
| Boulton Joinery Limited | Construction | 1997 |
| Bouncy Beans Ltd | Arts & recreation | 2025 |
| Bouncybrains Ltd | Information & communication | 2025 |
| Bound Over Limited | Transport & logistics | 2024 |
| Bourne Accountancy Limited | Professional & scientific | 2025 |
| Bournell Limited | Professional & scientific | 2010 |
| Bournheath Logistics Ltd | Transport & logistics | 2014 |
| Boutique Housekeeping Ltd | Administrative & support | 2017 |
| Boutique Living Collection Limited | Real estate | 2019 |
| Boveridge Transport Ltd | Transport & logistics | 2014 |
| BOW Boutique of Ashby Limited | Wholesale & retail | 2012 |
| Bowgreave Professional Ltd | Construction | 2014 |
| Bowill Management Ltd | Professional & scientific | 2021 |
| Bowing Engineering Ltd | Wholesale & retail | 2009 |
| Bowler James + Brindley Limited | Professional & scientific | 2013 |
| Bowling Green Holdings Ltd | Financial services | 2025 |
| Bowling Green Personnel Ltd | Administrative & support | 2025 |
| Bowlish Teamwork Ltd | Transport & logistics | 2014 |
| Bowman Interiors & Renovations Ltd | Construction | 2022 |
| Box 8 Ltd | Real estate | 2012 |
| Boxere Global Ltd | Wholesale & retail | 2020 |
| Boxeroo Ltd | Wholesale & retail | 2025 |
| Boxes and Board International Limited | Manufacturing | 2011 |
| Boxill Property Management Ltd | Real estate | 2023 |
| Boxxd Ltd | Hospitality | 2025 |
| Boxy Limited | Manufacturing | 2014 |
| Boyal UK Properties Ltd | Real estate | 2023 |
| Boyd Sport & Play Limited | Wholesale & retail | 1997 |
| Boyer Place Ltd | Real estate | 2018 |
| Bozoor Ltd | Information & communication | 2019 |
| Bozzles ARK Veterinary Practice Ltd | Professional & scientific | 2025 |
| BP Builders PVT Ltd | Construction | 2024 |
| BP Car Wash Forest Town Ltd | Wholesale & retail | 2026 |
| BP Doon Spice Limited | Hospitality | 2025 |
| BP Investments Ltd | Financial services | 2026 |
| BP Transport Services Limited | Transport & logistics | 2022 |
| BPC (Holdings) Limited | Real estate | 2011 |
| BPC Chandarana + Co Limited | Professional & scientific | 2004 |
| BPC Circuits LLP | | 2010 |
| BPC Electronics Limited | Manufacturing | 1993 |
| BPC Microwave Technology Ltd | Manufacturing | 2024 |
| BPC Transport Ltd | Transport & logistics | 2025 |
| BPC Wealth Management Limited | Financial services | 2016 |
| Bpduk Limited | Hospitality | 2023 |
| BPG Consultants Ltd | Professional & scientific | 2020 |
| Bphuk Limited | Hospitality | 2023 |
| BPM Construction Ltd | Construction | 2021 |
| BPMS02 Limited | Manufacturing | 2023 |
| BPMS11 Limited | Manufacturing | 2023 |
| BPMS12 Limited | Manufacturing | 2023 |
| BPMS13 Limited | Manufacturing | 2023 |
| BPMS14 Limited | Manufacturing | 2023 |
| BPO Investments Limited | Construction | 2024 |
| BPP Enterprise Ltd | Real estate | 2023 |
| Bppg Ltd | Construction | 2025 |