| Biotex Medical Ltd | Wholesale & retail | 2023 |
| Biotope Aquatics Limited | Wholesale & retail | 2016 |
| Birch & Nest Limited | Health & social care | 2025 |
| Birch & Vara Ltd | Wholesale & retail | 2023 |
| Birch Corner Limited | Hospitality | 2015 |
| Birch Grove Architecture Limited | Professional & scientific | 2020 |
| Birch Grove Engineering Limited | Professional & scientific | 2022 |
| Birch Hall Buildings Holdings Limited | Real estate | 2024 |
| Birch Hall Buildings Limited | Construction | 2015 |
| Birch View Health Care Limited | Health & social care | 2023 |
| Birchdean Limited | Hospitality | 2021 |
| Birchemploy Limited | Professional & scientific | 2003 |
| Birchwood and Co Case Management Ltd | Health & social care | 2020 |
| Birdwell Insulation Limited | Other services | 1993 |
| Birdwells Services Ltd | Manufacturing | 2022 |
| Birk & Sons Limited | Arts & recreation | 2019 |
| Birk Holdings Limited | Financial services | 2017 |
| Birkhaus Ltd | Arts & recreation | 2024 |
| Birks Motors Ltd | Wholesale & retail | 2023 |
| Birley & Carr Holdings Limited | Information & communication | 2016 |
| Birley Chiropractic Clinic Ltd | Health & social care | 2013 |
| Birley Court Management Company Limited | Real estate | 1986 |
| Birley Grange Developments Limited | Extraterritorial | 2024 |
| Birley Grange Properties Ltd | Extraterritorial | 2024 |
| Birley Local Ltd | Wholesale & retail | 2025 |
| Birley Moor Garden Centre Limited | Wholesale & retail | 1993 |
| Birley Properties Ltd | Real estate | 2018 |
| Birley Vale Developments Ltd | Professional & scientific | 2022 |
| Birleymoor News Limited | Wholesale & retail | 2015 |
| Birleymoor Windows Limited | Construction | 2016 |
| Birtwistle & Co Limited | Professional & scientific | 2012 |
| Biryani Dhaba Ltd | Hospitality | 2024 |
| Biscographic Ltd | Professional & scientific | 2017 |
| Bishop Barbershop Ltd | Other services | 2025 |
| Bismillah Estates Ltd | Construction | 2020 |
| Bismillah News Ltd | Information & communication | 2019 |
| Bison Car Parts Limited | Wholesale & retail | 2021 |
| Bison Grass Films Limited | Information & communication | 2008 |
| Bison Parts Limited | Wholesale & retail | 2014 |
| Bison Parts Properties Limited | Transport & logistics | 2018 |
| Bistrobar Limited | Hospitality | 2023 |
| Bistrobar Wine Limited | Hospitality | 2024 |
| Bitca Limited | Arts & recreation | 2003 |
| Bitcap Holdings Limited | Professional & scientific | 2013 |
| Bite Risk Electrolysis Project CIC | Wholesale & retail | 2025 |
| Bite Size Food Ltd | Hospitality | 2019 |
| Bite Tour Catering Limited | Hospitality | 2018 |
| Bitech Ltd | Construction | 2007 |
| Bithstone Carpets Limited | Wholesale & retail | 1999 |
| Bitpipe Consulting Ltd | Professional & scientific | 2017 |
| Bitri Steel Fixing Limited | Construction | 2022 |
| Bitscape Technology Services UK Ltd | Information & communication | 2024 |
| Bitvalley Ltd | Information & communication | 2022 |
| BIY (Hawes) Ltd | Wholesale & retail | 2023 |
| Biya Faisal Ltd | Wholesale & retail | 2025 |
| Bizzy Lets Ltd | Real estate | 2020 |
| BJ Bright Day Nurseries Limited | Education | 2004 |
| Bjar Ltd | Wholesale & retail | 2026 |
| Bjkr Limited | Professional & scientific | 2018 |
| BJL Events Limited | Hospitality | 2025 |
| Bjluna Ltd | Real estate | 2025 |
| BJR Racing Ltd | Arts & recreation | 2024 |
| BK Aquadrain UK Ltd | Wholesale & retail | 2024 |
| BK Boundary Road Ltd | Hospitality | 2025 |
| BK Business Ltd | Hospitality | 2026 |
| BK Car Transport Limited | Transport & logistics | 2017 |
| BK Convenience Store Ltd | Wholesale & retail | 2025 |
| BK Local Ltd | Wholesale & retail | 2025 |
| BK Motorcycle Tours Ltd | Administrative & support | 2026 |
| Bk&Fn Property Ltd | Real estate | 2026 |
| Bkay Limited | Information & communication | 2025 |
| BKB Synergy Ltd | Information & communication | 2025 |
| BKY Health & Lifestyle Coaching Ltd | Professional & scientific | 2025 |
| BKY Personal Training Ltd | Education | 2025 |
| BL Fibre Ltd | Information & communication | 2025 |
| BLA Home Ltd | Real estate | 2025 |
| Blac Aura Limited | Wholesale & retail | 2023 |
| Black Blossom Ltd | Financial services | 2021 |
| Black Boat Limited | Wholesale & retail | 2025 |
| Black Bright Theatre Company Limited | Arts & recreation | 2024 |
| Black Bull Hospitality Ltd | Hospitality | 2019 |
| Black Diamond Group Limited | Financial services | 2022 |
| Black Dog Imaging Limited | Health & social care | 2017 |
| Black Environment Network | Health & social care | 1995 |
| Black EYE Holdings Ltd | Financial services | 2020 |
| Black Focus Records Ltd | Information & communication | 2017 |
| Black Forge Consulting Ltd | Professional & scientific | 2026 |
| Black Heart Control & Automation Ltd | Manufacturing | 2024 |
| Black Heart Equestrian Limited | Wholesale & retail | 2017 |
| Black Jumper Software Limited | Information & communication | 2000 |
| Black Kite Transport Ltd | Transport & logistics | 2022 |
| Black Lion Rdhm Ltd | Hospitality | 2025 |
| Black Magic Audio Ltd | Professional & scientific | 2022 |
| Black Maple Games Ltd | Professional & scientific | 2012 |
| Black Oak Security Limited | Other services | 2018 |
| Black Orange Limited | Professional & scientific | 2020 |
| Black Owned Sheffield CIC | Information & communication | 2024 |
| Black Panthar Ltd | Real estate | 2024 |
| Black Range Limited | Water & waste | 1965 |
| Black Sea Motors Ltd | Wholesale & retail | 2020 |