| Bille Advisory & Consultancy Services UK Ltd | Transport & logistics | 2023 |
| Billies Cafe & Kitchen Ltd | Hospitality | 2025 |
| Billington Signs Limited | Manufacturing | 2003 |
| Billions Property Limited | Real estate | 2022 |
| Billitteri Limited | Hospitality | 2021 |
| Billman Automation Ltd | Wholesale & retail | 2019 |
| Billpilot Ltd | Information & communication | 2026 |
| Billtrucker Ltd | Transport & logistics | 2021 |
| Billy Driscoll Music Limited | Arts & recreation | 2026 |
| Billy Goats & Rain Coats Ltd | Wholesale & retail | 2018 |
| Billy's Bikes Ltd | Manufacturing | 2020 |
| Bilobos & Co Ltd | Health & social care | 2024 |
| Bilobos Investments Ltd | Real estate | 2023 |
| Bilton Veterinary Centre Limited | Extraterritorial | 2004 |
| Biltong Bites Limited | Manufacturing | 2016 |
| Bimcorp Holdings Limited | Construction | 2020 |
| Bimcorp Limited | Construction | 2020 |
| Bimotech Solutions Ltd | Information & communication | 2011 |
| Bimx Limited | Professional & scientific | 2024 |
| Binani UK Limited | Wholesale & retail | 2020 |
| Binary Helix Limited | Information & communication | 2013 |
| Binary IT Consulting Limited | Professional & scientific | 2012 |
| Binay Ltd | Wholesale & retail | 2026 |
| Bind and Brew Ltd | Extraterritorial | 2024 |
| Bind Media Ltd | Information & communication | 2018 |
| Bindari Trade Company Ltd | Transport & logistics | 2024 |
| Binding Group Limited | Arts & recreation | 2012 |
| Binding Properties Limited | Real estate | 2025 |
| Bindl Limited | Wholesale & retail | 2023 |
| Bing Bong Property Services Ltd | Manufacturing | 2017 |
| Bingol Intensives Ltd | Education | 2023 |
| Bingsu Limited | Health & social care | 2026 |
| Bini Letting Limited | Real estate | 2025 |
| Binimiser Ltd | Wholesale & retail | 2025 |
| Binita Dyson Consulting Limited | Professional & scientific | 2013 |
| Binlets Limited | Real estate | 2013 |
| Binopolis Ltd | Wholesale & retail | 2013 |
| Binostro LP | | 2011 |
| Binstead Systems Limited | Information & communication | 1995 |
| Binzee Won’T Fit Binzee IT Limited | Wholesale & retail | 2024 |
| BIO CHI Ltd | Wholesale & retail | 2016 |
| Bio-Leadership Ecosystem Group Ltd | Education | 2021 |
| Bioboon Agrology Limited | Professional & scientific | 2020 |
| Biochar Engineering Services Ltd | Professional & scientific | 2022 |
| Biochem Technology LLP | | 2006 |
| Biodiversity 25 Limited | Information & communication | 2023 |
| Bioenvirotec Limited | Professional & scientific | 2016 |
| Biohybrid Devices Limited | Manufacturing | 2024 |
| Bioinsight Ltd | Professional & scientific | 2010 |
| Bioma Health Ltd | Health & social care | 2022 |
| Biomedinc Ltd | Extraterritorial | 2023 |
| Bioniccrm Limited | Information & communication | 2020 |
| Bionicexo Ltd | Professional & scientific | 2023 |
| Biophile Limited | Professional & scientific | 2014 |
| Biosocius Ltd | Professional & scientific | 2016 |
| Biostatistical Solutions Ltd | Information & communication | 2012 |
| Biotak Limited | Wholesale & retail | 2010 |
| Biotec Diagnostics UK Ltd | Manufacturing | 2014 |
| Birakos Holdings Ltd | Real estate | 2023 |
| Biral Holdings Limited | Financial services | 2014 |
| Birbeck Property Limited | Real estate | 2022 |
| Birch Brothers Limited | Extraterritorial | 2023 |
| Birch Builders Limited | Construction | 2007 |
| Birch Design Ltd | Professional & scientific | 2019 |
| Birch Hill Wood Limited | Real estate | 2025 |
| Birch Media Design Ltd | Professional & scientific | 2015 |
| Birch Tree Books Ltd. | Information & communication | 2016 |
| Birchfield Limited | Real estate | 2001 |
| Birchills Telecom Limited | Information & communication | 2008 |
| Birchline Ltd | Administrative & support | 2024 |
| Birchmire Homes Limited | Real estate | 2019 |
| Birchwood Close Management Company Limited | Households | 2022 |
| Birchwood Price Tools Limited | Wholesale & retail | 2026 |
| Birchwood View Ltd | Construction | 2012 |
| Bird & Gorton Ltd | Professional & scientific | 2023 |
| Bird a Day Films Ltd | Information & communication | 2024 |
| Bird and Pest Solutions Ltd | Agriculture & fishing | 2009 |
| Bird Brain Consultancy Limited | Professional & scientific | 2022 |
| Bird in Hand (Long Ashton) Ltd | Hospitality | 2020 |
| Bird Industries Ltd | Information & communication | 2022 |
| Birda Ltd | Hospitality | 2026 |
| Birdcombe Estates Limited | Real estate | 2006 |
| Birdfish Productions Ltd | Other services | 2015 |
| Birdfood Ltd | Hospitality | 2017 |
| Birdhouse Property Ltd | Hospitality | 2022 |
| Birds Community Allotments Ltd | Real estate | 2022 |
| Birds Farm Holdings Ltd | Construction | 2018 |
| Birds Valeting Ltd | Administrative & support | 2021 |
| Birdstone Digital Ltd | Information & communication | 2021 |
| Birdwell School | Education | 2013 |
| Birkin Street Properties Ltd | Real estate | 2024 |
| Birmingham Healthcare Services (Holdings) Limited | Real estate | 2002 |
| Birmingham Healthcare Services Limited | Real estate | 2002 |
| Birnbeck Lodge Limited | Construction | 2020 |
| Birnbeck Mansions Management Co. Limited | Households | 1989 |
| Birtley Battery Storage Limited | Energy | 2024 |
| Bishop & Company (MSN) Limited | Financial services | 2017 |
| Bishop and Calvert Ltd. | Wholesale & retail | 1989 |
| Bishop and Finch Ltd | Wholesale & retail | 2021 |
| Bishop Property Rentals Limited | Real estate | 2023 |