| Bmhi Services Limited | Construction | 2018 |
| Bmib 2005 Holdings Limited | Financial services | 2023 |
| Bmib 2005 Limited | Financial services | 2005 |
| Bmib Limited | Wholesale & retail | 2000 |
| Bmrvisuals Ltd | Professional & scientific | 2026 |
| Bmyg Youth Work CIC | Administrative & support | 2017 |
| BNA Limited | Professional & scientific | 2013 |
| Board in Brum Ltd | Wholesale & retail | 2017 |
| Boat Food Ltd | Hospitality | 2023 |
| Boatmans Rest Limited | Hospitality | 2025 |
| BOB Shop 20 Ltd | Wholesale & retail | 2024 |
| BOB Shop 24 Ltd | Wholesale & retail | 2025 |
| Bob.Health Ltd | Information & communication | 2019 |
| Bobbyo Property Limited | Real estate | 2025 |
| Bobs Bifolds Limited | Construction | 2023 |
| Bodmide Shelter CIC | Real estate | 2024 |
| Bodrum Shrewsbury Limited | Hospitality | 2019 |
| Body Image UK Pole & Aerial Arts Academy Ltd | Arts & recreation | 2013 |
| Body Precision Training Ltd | Other services | 2025 |
| Body Shock Limited | Wholesale & retail | 1997 |
| Bogdan-Andrei Logistics Ltd | Transport & logistics | 2016 |
| Bojec Ltd | Administrative & support | 2021 |
| Boldmere Builders Limited | Construction | 2012 |
| Boltfast Limited | Wholesale & retail | 1971 |
| Boltight Limited | Manufacturing | 1999 |
| Boltmark Advertising and Marketing Ltd | Professional & scientific | 2025 |
| Bomere Fish Bar Limited | Hospitality | 2017 |
| Bon-Hol Electrical Ltd | Manufacturing | 2025 |
| Bonaventura Estates Limited | Real estate | 2012 |
| Bone and Joint Infection Society C.I.C. | Administrative & support | 2023 |
| Bonner Logistics Limited | Extraterritorial | 2004 |
| Bonner Studs Limited | Manufacturing | 2006 |
| Bonpop Limited | Wholesale & retail | 2015 |
| Bonwork Limited | Wholesale & retail | 1985 |
| Boogie Bounce Xtreme Limited | Arts & recreation | 2014 |
| Book Activity Ltd | Information & communication | 2026 |
| Book My Van Ltd | Transport & logistics | 2022 |
| Bookallcare Limited | Information & communication | 2025 |
| Booker Cole Limited | Professional & scientific | 2009 |
| Bookmycare.Com Ltd | Information & communication | 2026 |
| Bookworm Babies UK Ltd | Wholesale & retail | 2024 |
| Boora Ltd | Hospitality | 2023 |
| Boost Lettings Ltd | Real estate | 2010 |
| Boost Lifestyle Nootropics Ltd | Wholesale & retail | 2025 |
| Booze Land (Walsall) Ltd | Wholesale & retail | 2018 |
| Boparai Properties Limited | Real estate | 2013 |
| Borad Services Ltd | Transport & logistics | 2019 |
| Borneo Street Allotments CIC | Agriculture & fishing | 2025 |
| Borzasi Ltd | Transport & logistics | 2020 |
| Borzi Ltd | Transport & logistics | 2016 |
| BOS International Capital Limited | Wholesale & retail | 2024 |
| Bosim Limited | Real estate | 2016 |
| Boss Coffee Company Limited | Hospitality | 2021 |
| Boss MAN Store Ltd | Wholesale & retail | 2023 |
| Boss Security Solutions Ltd | Extraterritorial | 2021 |
| Boss UK Solutions Limited | Transport & logistics | 2014 |
| Boster's Kitchen & Café Ltd | Hospitality | 2024 |
| Bostin' Creative Arts & Theatre C.I.C. | Arts & recreation | 2018 |
| Bosty Fields Ltd | Arts & recreation | 2020 |
| Bosty Woods Ltd | Arts & recreation | 2005 |
| Botany House 32 Ltd | Health & social care | 2025 |
| Botond Automotive Limited | Wholesale & retail | 2022 |
| Boucle Hair Limited | Other services | 2025 |
| Boujeè&Cutefashionforpets Ltd | Wholesale & retail | 2025 |
| Boulevard Properties Limited | Real estate | 2019 |
| Bounce Around Castle Hire Limited | Extraterritorial | 2022 |
| Bouncing Statistics CIC | Education | 2020 |
| Bouncing Statistics Services Ltd | Education | 2021 |
| Bourne Vale (Management) Limited | Extraterritorial | 2020 |
| Bourne Vale Stables Limited | Arts & recreation | 2020 |
| Bournes Legal Ltd | Professional & scientific | 2018 |
| Boutique Properties Ltd | Real estate | 2023 |
| Bowater Plumbing & Heating Services Limited | Construction | 2023 |
| Bowman Stor Limited | Manufacturing | 1998 |
| Bowman's Consultancy Limited | Professional & scientific | 2017 |
| Box Smart Elite Boxing Club Limited | Arts & recreation | 2022 |
| Boxes Direct Limited | Wholesale & retail | 2005 |
| Boxes Made to Measure Ltd | Manufacturing | 2026 |
| Boxman Right Transport Ltd | Transport & logistics | 2022 |
| Boxtree Ltd | Health & social care | 2025 |
| Boxwood (London) Limited | Real estate | 2011 |
| BP Eyecare (Crewe) Ltd | Wholesale & retail | 2026 |
| BP Health Limited | Health & social care | 2019 |
| BP Online Trading Ltd | Wholesale & retail | 2017 |
| BP Roofing Limited | Construction | 2021 |
| BPH Live Ltd | Administrative & support | 2018 |
| BPM Finance Ltd | Hospitality | 2018 |
| BPP Properties Limited | Real estate | 2007 |
| Bptm Investments Limited | Real estate | 2021 |
| BR Global Limited | Wholesale & retail | 2026 |
| BR Property Maintenance Ltd | Households | 2019 |
| Bradbury Improvements Ltd | Construction | 2019 |
| Bradley International Ltd | Transport & logistics | 2026 |
| Bradley Watkins Ltd | Construction | 2006 |
| Brady Brothers Limited | Extraterritorial | 2008 |
| Braidsdavivy Salon Limited | Other services | 2024 |
| Brand Positioning Limited | Professional & scientific | 2005 |
| Brand Source Limited | Wholesale & retail | 2024 |
| Brandedheart Ltd | Real estate | 2026 |
| Brandline Store Limited | Wholesale & retail | 2024 |