| Bairstow Properties Ltd. | Real estate | 2020 |
| Bairstow's Group Limited | Financial services | 2022 |
| Bairstow's Mechanical Services Ltd | Construction | 2013 |
| Bairstows Property Solutions Ltd | Real estate | 2024 |
| Baisheng Food Service Ltd | Hospitality | 2026 |
| Baitcomps Ltd | Arts & recreation | 2026 |
| Baiwest Recruitment Ltd | Administrative & support | 2024 |
| BAJ Global Limited | Information & communication | 2017 |
| BAJ Global Media Services Ltd | Information & communication | 2025 |
| Bajaard Ltd | Health & social care | 2023 |
| Bajrang Global Trading Ltd | Wholesale & retail | 2026 |
| Bajwa Transport Care Limited | Transport & logistics | 2025 |
| Baka Cards Limited | Wholesale & retail | 2026 |
| Baka Holdings Limited | Financial services | 2026 |
| Bake ME a Wish Ltd | Manufacturing | 2021 |
| Baker & Co Ltd. | Professional & scientific | 2006 |
| Baker Brothers (Litho) Limited | Manufacturing | 1955 |
| Baker Clark Limited | Wholesale & retail | 2012 |
| Baker Francis Limited | Real estate | 2025 |
| Baker Group Executive Ltd | Administrative & support | 2025 |
| Baker Harding Limited | Administrative & support | 2005 |
| Baker Recruitment Group Ltd | Administrative & support | 2018 |
| Baker Recruitment Holdings Ltd | Financial services | 2023 |
| Bakes by Vanilla Bean Leeds Ltd | Hospitality | 2025 |
| Bakesy Bakery Ltd | Manufacturing | 2025 |
| Bakewell Project Investments Limited | Administrative & support | 2019 |
| Bakhit Ltd | Health & social care | 2026 |
| Bakhtyar Nishat Limited | Transport & logistics | 2025 |
| Baks Properties Ltd | Real estate | 2025 |
| Baktash Logistics Ltd | Transport & logistics | 2026 |
| BAL House Limited | Households | 2024 |
| Bal's Cafe Ltd | Hospitality | 2026 |
| Bala Forecourt Ltd | Wholesale & retail | 2024 |
| Bala Pritam AK Ltd | Education | 2025 |
| Bala SAT Limited | Administrative & support | 2012 |
| Balamoon Limited | Professional & scientific | 1994 |
| Balan Florin Ltd | Transport & logistics | 2016 |
| Balance Bay Limited | Other services | 2023 |
| Balance Fertility Limited | Health & social care | 2017 |
| Balance Health Limited | Health & social care | 2017 |
| Balance Mind Limited | Extraterritorial | 2017 |
| Balance Pro Ltd | Professional & scientific | 2025 |
| Balance Reproductive Health Limited | Health & social care | 2021 |
| Balance Sheet Protectors Limited | Extraterritorial | 2021 |
| Balanced Consult Ltd. | Professional & scientific | 2017 |
| Balanced Oncology Limited | Health & social care | 2019 |
| Balanced Therapy Ltd | Public administration | 2024 |
| Balbir Singh Dance Company | Arts & recreation | 2005 |
| Balesteir Associates Limited | Professional & scientific | 2025 |
| Bali Holdings Limited | Real estate | 2016 |
| Balica Courier Ltd | Transport & logistics | 2025 |
| Balica Transport Ltd | Transport & logistics | 2017 |
| Balkan Energy Associates Limited | Professional & scientific | 2024 |
| Balkan Energy Transition LP | | 2023 |
| Balkan Group Limited | Construction | 2019 |
| Ball and Berry Limited | Administrative & support | 2007 |
| Ball Eyecare Consulting Ltd | Health & social care | 2022 |
| Ball Rolling (Methley) Limited | Real estate | 2024 |
| Ball Rolling (Seaton) Limited | Real estate | 2024 |
| Ball Rolling (York) Limited | Real estate | 2024 |
| Ball Rolling Developments 1 Ltd | Construction | 2024 |
| Ball Rolling Investments Ltd | Real estate | 2024 |
| Ball Rolling Ltd | Real estate | 2022 |
| Ballantyne & Wood Commercial Cleaning Solutions Ltd | Administrative & support | 2026 |
| Ballard Innovations Limited | Manufacturing | 2025 |
| Ballena Ltd | Real estate | 2022 |
| Ballet Lifestyle Limited | Real estate | 2014 |
| Balloon Delight & Decor Limited | Hospitality | 2021 |
| Balmain Business Consulting Ltd | Professional & scientific | 2018 |
| Balmoral Investments Limited | Real estate | 2002 |
| Balmoral Mossman Limited | Professional & scientific | 2014 |
| Baloon Software Ltd | Information & communication | 2025 |
| Balstan Homes Limited | Construction | 2014 |
| Balta Chill Ltd | Other services | 2025 |
| Baltic Forest Lines Limited | Information & communication | 1998 |
| Balveur Ltd | Wholesale & retail | 2022 |
| Baly Trans Ltd | Transport & logistics | 2018 |
| Bambi Investments Ltd | Real estate | 2017 |
| Bambinadel Ltd | Transport & logistics | 2025 |
| Bamboo Grove Properties Ltd | Construction | 2024 |
| Bamboo Orchard Holdings Ltd | Financial services | 2023 |
| Bamboo Orchard Ltd | Information & communication | 2019 |
| Bamboo Tranquillity Spa Ltd | Other services | 2025 |
| Bambu Lettings Ltd | Real estate | 2022 |
| Bambu Property Developments Ltd | Real estate | 2022 |
| Bamburgh Castle Viewing Limited | Arts & recreation | 2011 |
| Bambú Group Ltd | Other services | 2022 |
| Bamford Industries Limited | Professional & scientific | 2025 |
| Bamforth and Company,Limited | Extraterritorial | 1910 |
| Bamforth Building Limited | Construction | 2015 |
| Bamin UK - China Cultural Cooperation Ltd | Professional & scientific | 2026 |
| Bamma and SON Limited | Construction | 2026 |
| Bampton Ltd | Hospitality | 2025 |
| Banana Candy Aesthetics Ltd | Other services | 2020 |
| Banana Properties Commercial & Residential Ltd | Real estate | 2024 |
| Banas Corner Ltd | Hospitality | 2026 |
| Bancroft Training Consultancy Limited | Professional & scientific | 2014 |
| Bandlink Limited | Arts & recreation | 1992 |
| Bandt Developments Ltd | Construction | 2025 |
| Banfro Healthcare Ltd | Health & social care | 2018 |