| BGM IT Consulting Limited | Information & communication | 2018 |
| BGM Midlands Ltd | Administrative & support | 2019 |
| Bgpa Limited | Information & communication | 2022 |
| BGS Northwest Developments Limited | Real estate | 2010 |
| Bgva Limited | Professional & scientific | 2026 |
| BH (Summermist) Limited | Hospitality | 2020 |
| BH Alderwood Limited | Hospitality | 2021 |
| BH Central Services Limited | Hospitality | 2020 |
| BH Ilford Limited | Hospitality | 2020 |
| BH Services Limited | Professional & scientific | 2025 |
| Bhagavan Ramana Enterprises Limited | Health & social care | 2024 |
| BHC Technology Limited | Professional & scientific | 2008 |
| Bhcs Magnolia Limited | Hospitality | 2025 |
| Bhqc Holdings Limited | Health & social care | 2018 |
| Bhrp Ltd | Administrative & support | 2024 |
| Bhstw Ltd | Manufacturing | 2026 |
| BI and K Ltd | Health & social care | 2015 |
| Bichonlove Puppy Rescue CIC | Agriculture & fishing | 2022 |
| Bickerstaffe & Co Ltd | Professional & scientific | 1999 |
| Bickford Electrical Ltd | Construction | 2018 |
| Bidsmile Limited | Information & communication | 2026 |
| Big BEN Lifting Ltd | Construction | 2025 |
| Big BEN Smash Burgers Ltd | Hospitality | 2026 |
| Big Blue Sky Consulting Limited | Administrative & support | 2014 |
| Big Cat Couriers Ltd | Transport & logistics | 2020 |
| Big Data Consulting Limited | Information & communication | 2012 |
| Big DIG Landscapes Ltd | Administrative & support | 2014 |
| Big FAT Star Limited | Real estate | 2023 |
| Big Iron Solutions Limited | Information & communication | 2025 |
| Big Life Records Limited | Extraterritorial | 2020 |
| Big Pink Collective CIC | Education | 2025 |
| Big Tent Music Management Ltd | Arts & recreation | 2007 |
| Bigga Diamond Printing Limited | Other services | 2020 |
| Bigs Baps Ltd | Hospitality | 2025 |
| Bikes and E-Bikes Ltd | Wholesale & retail | 2022 |
| Bilfinger Construction UK Limited | Transport & logistics | 1989 |
| Bilfinger Piping Technologies UK Limited | Construction | 2016 |
| Bilfinger UK Limited | Construction | 2005 |
| Billington Garden Rooms Ltd | Manufacturing | 2022 |
| Billthecloud Limited | Administrative & support | 2013 |
| Billy's Brewco Limited | Hospitality | 2026 |
| Bilosh Ltd | Hospitality | 2025 |
| BIM Management Limited | Administrative & support | 2014 |
| BIM MEP Construction Ltd | Administrative & support | 2026 |
| BIM Ultra Ltd | Professional & scientific | 2025 |
| Bimesque Limited | Professional & scientific | 2018 |
| Bimmall Limited | Construction | 2017 |
| Bimmer Engineering Ltd | Manufacturing | 2024 |
| Binary Equipment Limited | Information & communication | 2014 |
| Binary Finery Ltd | Information & communication | 2025 |
| Bindon Ltd | Real estate | 2025 |
| Bingham Advisory Services Limited | Professional & scientific | 2020 |
| Bingswood Holding Limited | Extraterritorial | 2021 |
| Binkulis Enterprises Limited | Financial services | 2026 |
| Binstead Technical Designs Limited | Administrative & support | 2007 |
| BIO NET Gain Solutions Limited | Water & waste | 2022 |
| BIO Products Group Limited | Professional & scientific | 2015 |
| Bio-Zone Ltd | Wholesale & retail | 2022 |
| Biocare UV Limited | Manufacturing | 2021 |
| Bioloop Systems Ltd | Manufacturing | 2026 |
| Bioprene Ltd | Education | 2023 |
| Biora Limited | Professional & scientific | 2001 |
| Biosho Health Limited | Administrative & support | 2024 |
| Biot Energy Limited | Administrative & support | 2024 |
| Biotrace Property Holdings Ltd | Financial services | 2025 |
| Birch AB Ltd | Construction | 2024 |
| Birch Grove Projects Ltd | Professional & scientific | 2022 |
| Birch Medical Communications Limited | Administrative & support | 2016 |
| Birchways Management Company Limited | Households | 1997 |
| Birchwood Accounting Services Ltd | Professional & scientific | 2023 |
| Birchwood Bark Park Ltd | Other services | 2025 |
| Birchwood Computers Ltd | Information & communication | 2005 |
| Birchwood Design Services Limited | Administrative & support | 2007 |
| Birchwood Evangelical Church | Other services | 2008 |
| Birchwood GAS Services Limited | Construction | 2003 |
| Birchwood Golf Club (2019) Ltd | Wholesale & retail | 2019 |
| Birchwood Golf Club Limited | Arts & recreation | 1982 |
| Birchwood Mortgages Limited | Financial services | 2011 |
| Birchwood MOT Ltd | Wholesale & retail | 2016 |
| Birchwood Property Management Limited | Real estate | 2004 |
| Birdies Events Limited | Administrative & support | 2025 |
| BIS Henderson Limited | Administrative & support | 1995 |
| Biscetti Ltd | Administrative & support | 2022 |
| Bishop Interiors Ltd | Manufacturing | 2022 |
| Bishop Media Walls Limited | Manufacturing | 2025 |
| Bisn Holdings Limited | Manufacturing | 2014 |
| Bisn OIL Tools Ltd | Manufacturing | 2011 |
| Bisn TEC Ltd. | Manufacturing | 2008 |
| Bisous Bridal Boutique Ltd | Wholesale & retail | 2017 |
| BIT& Ltd | Administrative & support | 2024 |
| Bitumen Plant & Commercial Limited | Wholesale & retail | 2018 |
| BIW Data Services Limited | Information & communication | 2016 |
| BIZ Think Ltd | Administrative & support | 2012 |
| Bizarre Barber Ltd | Other services | 2025 |
| Bizaware Limited | Information & communication | 2024 |
| BJ Offshore OIL & GAS Technical Services Limited | Administrative & support | 2014 |
| BJB Property Ltd | Real estate | 2024 |
| BJH Clements Ltd | Real estate | 2024 |
| BJH Pharma Ltd | Professional & scientific | 2024 |
| BJL Services Limited | Administrative & support | 2023 |