| Breakfast Records LLP | | 2016 |
| Breaking UK Limited | Professional & scientific | 2026 |
| Breakout Leisure Ltd | Extraterritorial | 2024 |
| Breakwater Collective Ltd | Wholesale & retail | 2026 |
| Breathdx (UK) Limited | Health & social care | 2015 |
| Breathe Aviation Ltd | Other services | 2011 |
| Breathe Bookkeeping Ltd | Professional & scientific | 2022 |
| Breathe Smarter Limited | Professional & scientific | 2020 |
| Breckenridge Property Rental Limited | Real estate | 2017 |
| Brecklands (Siston Lane) Management Company Limited | Real estate | 2020 |
| Brecknell Family Company Ltd | Financial services | 2021 |
| Brecknell Holding Company Ltd | Financial services | 2021 |
| Bredd Limited | Manufacturing | 2024 |
| Bredoff & Pimentel Limited | Hospitality | 2026 |
| Breeny's Wooden Wonders Ltd | Wholesale & retail | 2024 |
| Breese Property Services Limited | Construction | 2017 |
| Breeze Consultants Limited | Professional & scientific | 2023 |
| Breezetech Solutions Ltd | Wholesale & retail | 2024 |
| Breezy Orca Ltd | Professional & scientific | 2025 |
| Brenell Training Consultants Limited | Professional & scientific | 2008 |
| Brennan Therapy Ltd | Other services | 2023 |
| Brennan Young Ltd | Professional & scientific | 2012 |
| Brent Knoll Construction Limited | Construction | 2020 |
| Brent Knoll Tadpoles Preschool Limited | Health & social care | 2006 |
| Brentry Care Limited | Health & social care | 2021 |
| Brentry Park Development Management Company Limited | Real estate | 2010 |
| Breogan Ltd | Information & communication | 2009 |
| Bret Willson Dressage International Limited | Wholesale & retail | 2011 |
| Bretoncider Ltd | Wholesale & retail | 2026 |
| Brett Clifford Brickwork Ltd | Construction | 2020 |
| Brett Holly Ltd | Construction | 2019 |
| Bretter Electrical Ltd | Construction | 2023 |
| Breuqmann Ltd | Professional & scientific | 2025 |
| Brevern Technical Limited | Administrative & support | 2012 |
| Brevill Limited | Professional & scientific | 2012 |
| Brevonian Limited | Households | 1977 |
| Brew Builder Limited | Wholesale & retail | 2014 |
| Brew Coffee & Bakery Ltd | Hospitality | 2024 |
| Brew Coffee Bar Ltd | Hospitality | 2026 |
| Brew Hammond Limited | Health & social care | 2013 |
| Brewcote Property Management Limited | Households | 1987 |
| Brewer Logic Limited | Information & communication | 2013 |
| Brewers Baroque RTM Company Limited | Hospitality | 2010 |
| Brewery Lane Ltd | Information & communication | 2020 |
| Brewhive Ltd | Manufacturing | 2023 |
| Brewhouse Commercial Limited | Real estate | 2022 |
| Brewhouse Holdings Limited | Real estate | 2014 |
| Brewtopian Ltd | Hospitality | 2025 |
| Brezinova Limited | Administrative & support | 2015 |
| Brezkin Ltd | Professional & scientific | 2024 |
| Brgs Recruitment Ltd | Other services | 2024 |
| BRI Taxi Limited | Transport & logistics | 2024 |
| Brian Daniel Ltd | Extraterritorial | 2026 |
| Brian Mcleish Consulting Limited | Professional & scientific | 2016 |
| Brian Nourse Design Ltd | Professional & scientific | 2012 |
| Brian Swain Ltd | Professional & scientific | 2006 |
| Brian Wogan Limited | Manufacturing | 1987 |
| Briant BMS Limited | Professional & scientific | 2014 |
| Briant Tyres and Exhausts Limited | Wholesale & retail | 2005 |
| Briars Enterprises Ltd | Information & communication | 2016 |
| Briarside House Management Company Limited | Households | 1985 |
| Briarsmead Limited | Professional & scientific | 2016 |
| Bricio Boni Services Limited | Professional & scientific | 2016 |
| Brick Accounting Ltd | Information & communication | 2026 |
| Brick and Bloom Ltd | Administrative & support | 2021 |
| Brick House 2026 Limited | Real estate | 2026 |
| Bricks and Acres Ltd | Real estate | 2022 |
| Bricks and Quarters Ltd | Real estate | 2020 |
| Bricks Don'T Roll Ltd | Real estate | 2017 |
| Brickshare Ltd | Households | 2026 |
| Brickstol Ltd | Arts & recreation | 2021 |
| Brides and Hairpins UK Ltd | Wholesale & retail | 2018 |
| Bridge Boys Ltd | Real estate | 2022 |
| Bridge Church for Life | Other services | 2026 |
| Bridge Connected Ltd | Financial services | 2018 |
| Bridge Corner Management Company Limited | Households | 2007 |
| Bridge House Clifton Management Company Limited | Households | 2006 |
| Bridge House Light Railway (2024) Limited | Professional & scientific | 2024 |
| Bridge Patisserie Limited | Wholesale & retail | 2003 |
| Bridge Quay Management Company Limited | Households | 2015 |
| Bridge Views Management Company Limited | Households | 2016 |
| Bridgebelle Ltd | Extraterritorial | 2013 |
| Bridgecroft Limited | Professional & scientific | 2012 |
| Bridgematch Limited | Information & communication | 2026 |
| Bridgenorth Music UK Limited | Information & communication | 2025 |
| Bridgepoint Health Care Ltd | Transport & logistics | 2025 |
| Bridges Design Associates Limited | Administrative & support | 2008 |
| Bridges Educational Consulting Limited | Professional & scientific | 2023 |
| Bridges for Communities | Education | 2010 |
| Bridget Harrison Limited | Professional & scientific | 2011 |
| Bridgetwo Limited | Professional & scientific | 2026 |
| Bridgeview (Bath) Limited | Real estate | 2014 |
| Bridgevision Limited | Administrative & support | 2025 |
| Bridgewick Limited | Financial services | 1997 |
| Bridgeyate Developments Limited | Construction | 2001 |
| Bridgeyate Limited | Professional & scientific | 2015 |
| Bridgeyate Property Services Ltd | Real estate | 2021 |
| Bridging Histories CIC | Administrative & support | 2023 |
| Bridgwater Consortium Limited | Professional & scientific | 2005 |
| Bridgwater MRY Limited | Wholesale & retail | 2019 |