| Bridge Fitness & Wellbeing Limited | Other services | 2015 |
| Bridge H Ltd | Construction | 2023 |
| Bridge Property Developments Ltd | Construction | 2018 |
| Bridge Valley Ventures Life Sciences I LP | | 2019 |
| Bridgefoot Residents Association 1995 Company Limited | Households | 1995 |
| Bridgeman Pension Consultancy Ltd | Professional & scientific | 2021 |
| Bridgespan Ltd | Wholesale & retail | 2024 |
| Bridgeway Education Service Ltd | Education | 2025 |
| Bridgeway Solicitors Ltd | Professional & scientific | 2011 |
| Bridgfield Holdings Ltd | Financial services | 2025 |
| Briefingsforbrexit Ltd | Information & communication | 2024 |
| Briggs Access Platforms Ltd | Construction | 2022 |
| Briggs Corporation Limited | Financial services | 2025 |
| Bright & Co Group Ltd | Health & social care | 2026 |
| Bright Can-Achieve UK Ltd | Education | 2025 |
| Bright Dentistry Limited | Health & social care | 2023 |
| Bright Future Finance Limited | Financial services | 2004 |
| Bright Humans Ltd | Professional & scientific | 2013 |
| Bright Pharmasmile Limited | Health & social care | 2018 |
| Bright Scholar (BCS) Property Limited | Education | 2018 |
| Bright Scholar (UK) Holdings Limited | Financial services | 2018 |
| Bright Tree Ltd | Real estate | 2005 |
| Bright Trigger Limited | Information & communication | 2026 |
| Brightbang Limited | Information & communication | 2015 |
| Brightcast Media Limited | Wholesale & retail | 2025 |
| Brightcel Software Limited | Information & communication | 2016 |
| Brightspark Media Limited | Arts & recreation | 2010 |
| Brightstar Retail Ltd | Wholesale & retail | 2021 |
| Brightstone Innovations Group Co., Limited | Information & communication | 2023 |
| Brightwell International Health Technology Co., Ltd | Manufacturing | 2025 |
| Brightwell Media Ltd | Information & communication | 2026 |
| Brigita Leon Ltd | Professional & scientific | 2026 |
| Brillia Living Technology Co., Ltd | Manufacturing | 2025 |
| Brilliant IP Co., Ltd | Professional & scientific | 2023 |
| Brima Holst&Crane Ltd | Extraterritorial | 2019 |
| Brimadell Property Developments Limited | Real estate | 1971 |
| Brimflex Limited | Manufacturing | 2009 |
| Brindley House Birmingham (UK) Ltd | Real estate | 2022 |
| Briskham Limited | Real estate | 2008 |
| Brit Double Glazing Limited | Construction | 2026 |
| Brit-Pax Limited | Wholesale & retail | 2020 |
| Britannia Properties Estates and Investments Ltd | Real estate | 2024 |
| Britannia Solutions Group Ltd | Wholesale & retail | 2025 |
| Britasia United Ventures Limited | Wholesale & retail | 2024 |
| Britclass Ltd | Transport & logistics | 2019 |
| Britesphere Ltd | Wholesale & retail | 2025 |
| Brittain Holdings Limited | Professional & scientific | 2018 |
| Britten Place (Block a) Management Company Limited | Households | 2015 |
| Britten Sinfonia Ltd. | Arts & recreation | 1980 |
| Britten Sinfonia Productions Limited | Arts & recreation | 2017 |
| Brittons Farming | Agriculture & fishing | 2007 |
| Britvac Ltd | Professional & scientific | 2019 |
| Brnikat Limited | Information & communication | 2009 |
| Brntprk Ltd | Other services | 2022 |
| BRO Bradea Composites Ltd | Manufacturing | 2023 |
| Broad Materials Co., Ltd | Wholesale & retail | 2022 |
| Broadband Genie (Holdings) Limited | Wholesale & retail | 2026 |
| Broadband Genie Ltd | Wholesale & retail | 2004 |
| Broadgate Fencing Limited | Construction | 2024 |
| Broadland Gate DM Limited | Construction | 2016 |
| Broadland Gate Estate Management Limited | Households | 2020 |
| Broadland Gate Land Limited | Construction | 2016 |
| Broadlane Supplies Ltd | Wholesale & retail | 2010 |
| Broadmeadow Consultancy Ltd | Professional & scientific | 2021 |
| Broadway House Management Company Limited | Households | 2001 |
| Broadya Technical Industrial Co., Limited | Manufacturing | 2023 |
| Brocail Ltd | Hospitality | 2023 |
| Brockmann Strategic Ltd | Financial services | 2026 |
| Broker Avenue Limited | Hospitality | 2022 |
| Broker Consortium Limited | Other services | 2011 |
| Bromham Builders Limited | Construction | 2005 |
| Bromham Group Limited | Financial services | 2005 |
| Bromley Property Services Ltd. | Wholesale & retail | 1997 |
| Brompt Ltd | Wholesale & retail | 2025 |
| Bromswold Property Limited | Real estate | 2024 |
| Bronzera Limited | Wholesale & retail | 2025 |
| Bronzerock View Park Limited | Hospitality | 2019 |
| Brook Business Services Limited | Administrative & support | 2012 |
| Brook Green Management Limited | Information & communication | 2023 |
| Brooke's Beauty & Spa Limited | Other services | 2019 |
| Brookfield Contracting & Farming Ltd | Agriculture & fishing | 2010 |
| Brookfield Group Ltd | Construction | 2025 |
| Brookgate (Hills Road) Limited | Real estate | 2002 |
| Brookgate Development Management Limited | Real estate | 2001 |
| Brookgate Developments Ltd | Construction | 2026 |
| Brookgate Homes Limited | Real estate | 2002 |
| Brookgate Land Limited | Construction | 2000 |
| Brookgate Limited | Administrative & support | 2009 |
| Brookgate Property Limited | Real estate | 1999 |
| Brooklands Court Limited | Real estate | 1997 |
| Brooklands House Limited | Professional & scientific | 2016 |
| Brooks & Co Group Limited | Other services | 2021 |
| Brooks Barbershop Chelmsford Limited | Administrative & support | 2017 |
| Brooks Barbershop Clacton Ltd | Other services | 2021 |
| Brooks Barbershop Colchester Limited | Other services | 2016 |
| Brooks Barbershop Leigh Ltd | Other services | 2025 |
| Brooks Epson Property Limited | Real estate | 2019 |
| Brooks-Hudson Innovation Limited | Professional & scientific | 2017 |
| Brookwood House Management Company Limited | Real estate | 2006 |
| Broome Consulting & Services Ltd | Manufacturing | 2024 |