| Brain Family Holdings Limited | Financial services | 2023 |
| Brain Family Investments Limited | Real estate | 2019 |
| Brain UP Education Services Ltd | Education | 2019 |
| Brainco Limited | Wholesale & retail | 2022 |
| Brains Hub Ltd | Information & communication | 2022 |
| Brainybirdz Limited | Professional & scientific | 2017 |
| Bramber Court (Slough) Management Company Limited | Real estate | 1983 |
| Brand by Design Limited | Professional & scientific | 2007 |
| Brand Concerto Limited | Professional & scientific | 2022 |
| Brand Live NOW Ltd | Professional & scientific | 2017 |
| Brand New Design Consultancy Limited | Professional & scientific | 2004 |
| Brand Sense Ltd | Wholesale & retail | 2022 |
| Brandless Digital Limited | Information & communication | 2017 |
| Brandnetics Limited | Professional & scientific | 2022 |
| Brando Developments Ltd | Construction | 2022 |
| Brandon Builders Ltd | Construction | 2022 |
| Brands Hill House Ltd | Hospitality | 2014 |
| Brandwiz Ltd | Extraterritorial | 2021 |
| Branstone Group Ltd | Real estate | 2022 |
| Brar & Lailna Estates Ltd | Real estate | 2023 |
| Brar Food Supplies Ltd | Wholesale & retail | 2022 |
| Brar Heating and Plumbing Ltd | Construction | 2021 |
| Brar Homes Limited | Real estate | 2019 |
| Brave Harbor Limited | Wholesale & retail | 2025 |
| Brave PR and Marketing Limited | Professional & scientific | 2024 |
| Bravespire Therapy Ltd | Health & social care | 2025 |
| Bravic Construction Ltd | Construction | 2020 |
| Bravo Healthcare Services Ltd | Health & social care | 2024 |
| Bravo Invest Ltd | Real estate | 2020 |
| Bravo IT Solutions Limited | Information & communication | 2011 |
| Bravo-Faraday & Associates Ltd | Professional & scientific | 2025 |
| Bravomusica Ltd | Professional & scientific | 2024 |
| Bravora ABH Ltd | Wholesale & retail | 2026 |
| Brbloomer Limited | Extraterritorial | 2007 |
| Breakout Linens Ltd | Wholesale & retail | 2025 |
| Breakspear (Ashford) Limited | Wholesale & retail | 1953 |
| Brennie’S Limited | Hospitality | 2019 |
| Brgtt Ltd | Real estate | 2024 |
| Brian Chilvers and Sons Limited | Wholesale & retail | 2002 |
| Brianna Cleaning Service Ltd | Administrative & support | 2024 |
| Brick & Fern Property Services Ltd | Construction | 2025 |
| Brick N Block Ventures Limited | Construction | 2026 |
| Brick Red Properties Limited | Real estate | 2026 |
| Brick-Row Building Solutions Ltd | Construction | 2021 |
| Brickbagz Limited | Wholesale & retail | 2024 |
| Bricknest Holdings Limited | Wholesale & retail | 2024 |
| Bricks & Water Holdings Limited | Real estate | 2021 |
| Bridal Clothes Ltd | Wholesale & retail | 2023 |
| Bridge Road RTM Company Ltd | Households | 2013 |
| Bridgehead (Europe) Limited | Professional & scientific | 2005 |
| Bridgehead (UK) Limited | Professional & scientific | 1995 |
| Bridging Cars Ltd | Administrative & support | 2026 |
| Bridging Gaps Consultancy Ltd | Professional & scientific | 2013 |
| Bridging Gaps Limited | Education | 2006 |
| Bridging London Limited | Administrative & support | 2015 |
| Bright Bridge Care Limited | Health & social care | 2025 |
| Bright Day Cars & Recovery Ltd | Wholesale & retail | 2012 |
| Bright DEE Limited | Transport & logistics | 2018 |
| Bright Educare Limited | Health & social care | 2022 |
| Bright Future Learning Ltd | Education | 2024 |
| Bright House Slough Ltd | Wholesale & retail | 2025 |
| Bright Money Holdings Ltd | Real estate | 2019 |
| Bright Red Moon Limited | Real estate | 2017 |
| Bright Services Group Ltd | Administrative & support | 2020 |
| Bright Space Knoll Ltd | Real estate | 2024 |
| Bright Space Partners Ltd | Real estate | 2023 |
| Bright Sparks Electrical BSE Ltd | Construction | 2026 |
| Bright Star Events C.I.C. | Administrative & support | 2021 |
| Bright World Nurseries Limited | Education | 2017 |
| Brightbooks Accounting Limited | Professional & scientific | 2025 |
| Brightday Care & Cleaning Services Ltd | Health & social care | 2024 |
| Brighter Concept Ltd | Construction | 2024 |
| Brighter Lifecare Services Ltd | Health & social care | 2021 |
| Brightpaarth Ltd | Information & communication | 2023 |
| Brightpathenglish Ltd | Education | 2026 |
| Brightroute Visas Limited | Professional & scientific | 2025 |
| Brightside Painting & Decorating Ltd | Construction | 2025 |
| Brightwell Trading Ltd | Wholesale & retail | 2025 |
| Brigth Mart Ltd | Wholesale & retail | 2026 |
| Brigway Ltd | Professional & scientific | 2024 |
| Brilliance Academy Limited | Education | 2011 |
| Brilliant Money Limited | Professional & scientific | 2022 |
| Brilliant Moves Ltd | Transport & logistics | 2023 |
| Brilliant T.V. Limited | Information & communication | 1991 |
| Brindhavan Limited | Wholesale & retail | 2019 |
| Brisk Work Ltd | Wholesale & retail | 2019 |
| Brit Build Group Ltd | Construction | 2016 |
| Brit Dynamic Engine Ltd | Wholesale & retail | 2025 |
| Brit Heating&Plumbing Ltd | Construction | 2025 |
| Brit Home Design Build Ltd | Construction | 2022 |
| Brit Lanka Ltd | Wholesale & retail | 2020 |
| Brit MAN4S Ltd | Construction | 2017 |
| Brit Readymix Concrete Limited | Other services | 2017 |
| Brit Services Group Limited | Administrative & support | 2012 |
| Britannia Auto Group Ltd | Wholesale & retail | 2023 |
| Britannia International Wholesalers Ltd | Wholesale & retail | 2018 |
| Britannia Trade Global Ltd | Wholesale & retail | 2026 |
| Britannica Properties Group Ltd | Real estate | 2003 |
| Britaura Ltd | Wholesale & retail | 2025 |
| BRITB2B Ltd | Information & communication | 2026 |