| Babymondo Limited | Wholesale & retail | 2024 |
| BAC Properties Limited | Real estate | 2024 |
| Bache Chiropody & Podiatry Ltd | Health & social care | 2013 |
| Bache Post & News Limited | Wholesale & retail | 2003 |
| Bachelors Lane Chester Limited | Construction | 2022 |
| Back on Track Physio Limited | Health & social care | 2005 |
| Back Yard Beans Ltd | Manufacturing | 2025 |
| Backford Cross Ltd | Real estate | 2025 |
| Badger's Walk (Chester) Management Company Limited | Households | 1988 |
| Bahay Kubo Ltd | Wholesale & retail | 2020 |
| Bahram Consulting Limited | Information & communication | 2014 |
| Bailey Rose Bakes Ltd | Manufacturing | 2025 |
| Bainbridges Auctioneers Limited | Administrative & support | 2022 |
| Bainbridges of Ruislip Limited | Administrative & support | 2022 |
| BAJ Apartments Ltd | Hospitality | 2025 |
| Baker and Roberts Limited | Wholesale & retail | 2017 |
| Bakerrisk Europe, Ltd | Professional & scientific | 1999 |
| Bakery Technical Services Ltd | Professional & scientific | 2022 |
| Balaji KI JAI Limited | Financial services | 2024 |
| Balancedhq Ltd | Professional & scientific | 2025 |
| Baling Wire Products Ltd | Administrative & support | 2013 |
| Ballantyne Grant Ltd | Administrative & support | 2010 |
| Ballinteni Investments Limited | Real estate | 2004 |
| Baltic GIN Ltd | Hospitality | 2018 |
| Baltic Professional Investment (UK) Limited | Financial services | 2021 |
| Bankrupt Bandits Limited | Wholesale & retail | 2024 |
| Bannal Lane Management Company Ltd | Administrative & support | 2017 |
| Bannel Dairy Farm Limited | Financial services | 2023 |
| Bar Turkish Barber 3 Ltd | Other services | 2021 |
| Baranswift Limited | Other services | 1999 |
| Barberzaar Ltd | Other services | 2020 |
| Bardern Estates Limited | Real estate | 2026 |
| Bare Treatments Ltd | Other services | 2023 |
| Bariatric Surgical Services Ltd | Health & social care | 2019 |
| Barkin Development and Property Company Limited | Construction | 2010 |
| Barlow Hairdressing Limited | Other services | 2012 |
| Barn OWL Property and Investment LLP | | 2017 |
| Barnacle Salt Limited | Information & communication | 2015 |
| Barnes Home Solutions Limited | Construction | 2018 |
| Barnfield Hughes Limited | Professional & scientific | 1979 |
| Barnfield Hughes Properties Limited | Real estate | 2014 |
| Barnhill Grange Management Company Limited | Households | 1987 |
| Barnhouse Veterinary Clinic Limited | Professional & scientific | 2010 |
| Barnschapel Ltd | Other services | 2020 |
| Barnston Developments Limited | Real estate | 2018 |
| Barnston Estate Solar Ltd | Energy | 2015 |
| Barre Balance Limited | Other services | 2019 |
| Barrel and Bird Ltd | Real estate | 2025 |
| Barrington Advisory Ltd | Professional & scientific | 2026 |
| Barron Commercial Cleaning Ltd | Administrative & support | 2021 |
| Barrow Clifford Ltd | Real estate | 2021 |
| Barrow Consulting Services Limited | Professional & scientific | 2015 |
| Barrowfield Holdings Limited | Financial services | 2024 |
| Barrowfield Property Developments Limited | Construction | 2024 |
| Barrowmore Limited | Health & social care | 2006 |
| Barrowmore Social Enterprises Limited | Hospitality | 2013 |
| Barry Callebaut Beverages UK Ltd | Manufacturing | 1986 |
| Barry Johnston Limited | Professional & scientific | 1998 |
| Barry Mulroney Ltd | Construction | 2014 |
| Bartex Design Limited | Arts & recreation | 2007 |
| Barwell Infinity LLP | | 2025 |
| Barwick House Holdings Ltd | Financial services | 2025 |
| Base Collective Limited | Administrative & support | 2025 |
| Base Intrinsic Ltd | Manufacturing | 2014 |
| Base IT Support Ltd | Administrative & support | 2015 |
| Basford Developments Limited | Construction | 1995 |
| Basford Trading Ltd | Wholesale & retail | 2020 |
| Bashco Ltd | Professional & scientific | 2018 |
| Battalion Digital Limited | Professional & scientific | 2017 |
| Bauldreay JET Fuel Consulting Ltd | Professional & scientific | 2019 |
| Baxley Chemicals Limited | Wholesale & retail | 2006 |
| Baytek Holdings Limited | Real estate | 2025 |
| Baytree Consulting Limited | Other services | 2015 |
| Baytree Property Ltd | Hospitality | 2019 |
| BB Stainless Steel Limited | Professional & scientific | 2007 |
| Bbacq Limited | Professional & scientific | 2022 |
| Bcmed Ltd | Professional & scientific | 2019 |
| Bcreative IT Solutions Limited | Information & communication | 2023 |
| BD Management Consulting Ltd. | Administrative & support | 2017 |
| BD Real Estate Investments Ltd | Real estate | 2025 |
| BD Tech Solutions Limited | Information & communication | 2020 |
| BDP B3-B4 RTM Company Limited | Households | 2023 |
| BDP Freehold Limited | Households | 2014 |
| BE & KEN Global Ltd | Wholesale & retail | 2021 |
| BE Inspired Homes Ltd | Real estate | 2025 |
| BE My Broker Limited | Financial services | 2020 |
| BE Residential Ltd | Real estate | 2015 |
| BE Right Limited | Real estate | 2025 |
| BE Your Own Guru Limited | Professional & scientific | 2002 |
| Beacons Management Company Limited(The) | Households | 1985 |
| Beam Collective Limited | Real estate | 2024 |
| Bean & Cole Ltd | Hospitality | 2018 |
| Bean to Cloud Nine Ltd | Hospitality | 2026 |
| Beanstalk Designs Ltd | Wholesale & retail | 2022 |
| Bear Surfacing Limited | Administrative & support | 2024 |
| Bears Mobile Exchange Limited | Wholesale & retail | 2025 |
| Beatrice Court Management (Oswestry) Limited | Hospitality | 2007 |
| Beau Comms Ltd | Professional & scientific | 2024 |
| Beaufort Financial Services Ltd | Professional & scientific | 2011 |
| Beaumont Court RTM Company Limited | Households | 2025 |