| Bird Gate Property Limited | Real estate | 2024 |
| Bird Logistics Ltd | Transport & logistics | 2008 |
| Birds and Bells Glamping Limited | Hospitality | 2026 |
| Birkett Abrasive Machinery Ltd | Manufacturing | 2025 |
| Birkin Properties Limited | Real estate | 2016 |
| Birkin Pullman Limited | Information & communication | 2024 |
| Birkinshaw Aesthetics Ltd | Health & social care | 2023 |
| Birley Automotive Ltd | Wholesale & retail | 2021 |
| Birley Manufacturing Limited | Manufacturing | 1999 |
| Birmingham HIP & Knee Clinic Ltd | Health & social care | 2019 |
| Birmingham Hospitality Association Limited | Other services | 2024 |
| Birmingham Pressings Limited | | 2002 |
| Birramontecassinouk Ltd | Wholesale & retail | 2022 |
| Birria Boyz Franchising Ltd | Professional & scientific | 2025 |
| Birria Boyz Kitchens Limited | Hospitality | 2025 |
| BIRSTWITH123 Limited | Financial services | 2017 |
| Birtanem Limited | Health & social care | 2017 |
| Bisa Wofa Ltd | Information & communication | 2025 |
| Bishop Properties (Leeds) Limited | Real estate | 2022 |
| Bishops Glade Management Company Limited | Real estate | 2018 |
| Biskit Limited | Professional & scientific | 2003 |
| Bismil Yorkshire Limited | Wholesale & retail | 2022 |
| Bison (Yorkshire) Ltd | Hospitality | 2018 |
| Bison Construction Yorkshire Ltd | Construction | 2022 |
| Bison Homes Yorkshire Limited | Construction | 2025 |
| Bison LS11 Ltd | Hospitality | 2018 |
| Bison Outbound Ltd | Professional & scientific | 2026 |
| Bison Power Ltd | Manufacturing | 2026 |
| Bisonel Ltd | Information & communication | 2022 |
| Bistro Morley Ltd | Hospitality | 2025 |
| Bistro Wines Ltd | Wholesale & retail | 2024 |
| Biswas Ltd | Real estate | 2020 |
| BIT by BIT Solutions Ltd | Information & communication | 2022 |
| BIT2 Ltd | Information & communication | 2019 |
| Bita's Mortgage Services Ltd | Financial services | 2018 |
| Bitamin Ltd | Information & communication | 2020 |
| Bitbrainy Ltd | Information & communication | 2024 |
| Bite Back! Events Ltd. | Education | 2024 |
| Biteology Ltd | Hospitality | 2024 |
| Bitestop Venders Ltd | Wholesale & retail | 2025 |
| Bitez (Leeds) Ltd | Hospitality | 2024 |
| Bitez (Yorkshire) Limited | Hospitality | 2025 |
| Bitfit Ltd | Information & communication | 2023 |
| Bitt Events Ltd | Other services | 2022 |
| Bivar Limited | Construction | 1992 |
| BIW Contracting Limited | Real estate | 2012 |
| BIW Properties Limited | Real estate | 2007 |
| Biwater House RTM Company Limited | Households | 2024 |
| BIY Energy Ltd | Administrative & support | 2021 |
| Biya 2 Ltd | Hospitality | 2025 |
| BIZ Investments Limited | Real estate | 2024 |
| BIZ Landline Ltd | Information & communication | 2025 |
| BIZ Property Investments Ltd | Real estate | 2023 |
| BIZ Transport Ltd | Transport & logistics | 2017 |
| Bizofdev Ltd | Information & communication | 2025 |
| BJ Computer Services Limited | Administrative & support | 2016 |
| BJ Properties Investments Limited | Real estate | 2022 |
| BJ World Limited | Construction | 2024 |
| BJB Consultancy Limited | Real estate | 1995 |
| BJB Consulting (UK) LLP | | 2009 |
| BJB Consulting Ltd | Professional & scientific | 2006 |
| BJB Electrical Ltd | Construction | 2025 |
| BJC Financial Services Ltd | Professional & scientific | 2020 |
| BJF Electrical Services Limited | Construction | 2018 |
| BJH Technology Limited | Administrative & support | 2015 |
| BJI Electrical Services Ltd | Construction | 2023 |
| Bjks Consulting Ltd | Professional & scientific | 2025 |
| BJP Holdings Limited | Financial services | 2005 |
| BJP Insurance Brokers Limited | Financial services | 1997 |
| BJQ Logistics Ltd | Transport & logistics | 2022 |
| BJR IT Solutions Limited | Administrative & support | 2016 |
| BJS Fabrications Ltd | Manufacturing | 2024 |
| BJS Powder Coating Ltd | Manufacturing | 2018 |
| BJT Associates Limited | Wholesale & retail | 2016 |
| BK Amlak Limited | Real estate | 2020 |
| BK Care Services Limited | Health & social care | 2023 |
| BK Commercial Landscaping and Ground Works Ltd | Manufacturing | 2023 |
| BK General and Prestige Cars Ltd | Wholesale & retail | 2020 |
| BK Innovations Limited | Health & social care | 2024 |
| BK Leeds Ltd | Wholesale & retail | 2025 |
| BK Liverpool Limited | Real estate | 2020 |
| BK Manchester Limited | Real estate | 2020 |
| BK Medical UK Limited | Administrative & support | 2014 |
| BK Nottingham Ltd | Hospitality | 2019 |
| BK Racing & Sons Limited | Arts & recreation | 2025 |
| BK Super Real Estate Ltd | Real estate | 2026 |
| BK Toys & Gadgets Limited | Wholesale & retail | 2023 |
| BK Web Ltd | Information & communication | 2020 |
| BK365 Ltd | Real estate | 2023 |
| BKC Yorkshire Limited | Construction | 2024 |
| BKG (Cotswolds) Ltd | Real estate | 2024 |
| BKI Lets Limited | Hospitality | 2009 |
| Bkind Care Ltd | Health & social care | 2018 |
| Bkopera Enterprisess Ltd | Administrative & support | 2025 |
| BKS Groundworks Holdings Limited | Construction | 2023 |
| BKS Groundworks Limited | Construction | 2019 |
| BKS Group Holdings Ltd | Construction | 2023 |
| BKS Holdings Limited | Professional & scientific | 2016 |
| BKS PAY and Benefits Limited | Administrative & support | 2026 |
| BKS Roofing Ltd | Construction | 2022 |