| Blexho Transport Ltd | Transport & logistics | 2023 |
| Blinc Investments Ltd | Administrative & support | 2017 |
| Blinds Factory Direct Ltd | Wholesale & retail | 2003 |
| Bliss Hair and Beauty Ltd | Other services | 2025 |
| Blitz Cyber Security Limited | Information & communication | 2024 |
| Blitz Transport Services Ltd | Transport & logistics | 2024 |
| Blond. (Harrogate) Ltd | Other services | 2023 |
| BLOND1E Limited | Extraterritorial | 2020 |
| Bloody Stuff Limited | Manufacturing | 2016 |
| Bloojam Consulting Limited | Professional & scientific | 2005 |
| Bloomdean Holding Limited | Hospitality | 2022 |
| Bloomdean Limited | Hospitality | 1999 |
| Bloss Ltd | Information & communication | 2021 |
| Bloxsa for Trading Ltd | Wholesale & retail | 2021 |
| Blue Diamond Care Ltd | Health & social care | 2022 |
| Blue Hawk Talent Solutions Limited | Administrative & support | 2020 |
| Blue Moon Yorkshire Limited | Administrative & support | 2017 |
| Blue Oak Homes (Yorkshire) Limited | Construction | 2015 |
| Blue Ocean Boardrooms Ltd | Professional & scientific | 2025 |
| Blue Otter Boats Ltd | Arts & recreation | 2017 |
| Blue Pebble Events Limited | Extraterritorial | 2010 |
| Blue Pencil Procurement Limited | Professional & scientific | 2014 |
| Blue Sky Consultants (EU) Ltd | Professional & scientific | 2013 |
| Blue Snow Energy (UK) Limited | Professional & scientific | 2013 |
| Blue Willow Heritage Limited | Professional & scientific | 2023 |
| Bluebeard's Barber Shop Limited | Other services | 2012 |
| Bluechip Consulting Ltd | Professional & scientific | 1995 |
| Bluedini Limited | Real estate | 2021 |
| BLUEJ24 Ltd | Manufacturing | 2011 |
| Bluestone Design Group Limited | Professional & scientific | 2000 |
| Blunt Property Management Limited | Real estate | 2020 |
| Blush Medical Aesthetics Ltd | Health & social care | 2022 |
| Bluubell Ltd | Information & communication | 2013 |
| BMG Finance Consultancy Ltd | Professional & scientific | 2023 |
| BMX Bandits Ltd | Extraterritorial | 2012 |
| BMX Legends Limited | Extraterritorial | 2012 |
| BMX MAS Ltd | Extraterritorial | 2012 |
| BNG (Yorkshire) Limited | Administrative & support | 2024 |
| BNR Properties Limited | Construction | 2005 |
| Bo&Co Properties Ltd | Hospitality | 2024 |
| BO55 Ltd | Extraterritorial | 2017 |
| Boardready Limited | Information & communication | 2026 |
| Boardside Limited | Professional & scientific | 2017 |
| Boars Head Developments Ltd | Real estate | 2020 |
| Boars Head Water Supply Company Limited | Water & waste | 2002 |
| Boatfield FLY Fishing Ltd | Manufacturing | 2022 |
| Boathouse Mull Limited | Hospitality | 2022 |
| BOB Salisbury Engineering Limited | Administrative & support | 1996 |
| Bocian Limited | Hospitality | 2012 |
| Bocox Limited | Hospitality | 2007 |
| Bodega Bar and Grill Limited | Hospitality | 2018 |
| Boden Group North Ltd | Professional & scientific | 2025 |
| Body Renewal Fitness & Wellbeing Limited | Education | 2026 |
| Boiler Squad Ltd | Extraterritorial | 2012 |
| Bolt Enterprise Ltd | Wholesale & retail | 2021 |
| Bolt Victory Limited | Professional & scientific | 2023 |
| Bomond Limited | Wholesale & retail | 2023 |
| Bond END Gardens Limited | Real estate | 2011 |
| Bond Housing Ltd | Real estate | 2019 |
| Bondevelopments (Yorkshire) Limited | Construction | 2021 |
| Bondgate Bakery Ltd | Manufacturing | 2007 |
| Book IT List Travel Ltd | Administrative & support | 2018 |
| Boomi Corporation Limited | Information & communication | 2014 |
| Boomi UK Holdings Ltd. | Financial services | 2021 |
| Boostar Corporate Limited | Information & communication | 2016 |
| Boot Tree Limited | Extraterritorial | 2025 |
| Booth Revolution Ltd | Professional & scientific | 2009 |
| Bootham Property Lettings Limited | Real estate | 2019 |
| Boothroyd Flanigan Ltd | Hospitality | 2023 |
| Booze Limited | Extraterritorial | 2025 |
| BOR1S Limited | Extraterritorial | 2020 |
| Bordeaux Limited | Extraterritorial | 2024 |
| Borealis Property Management Ltd | Real estate | 2025 |
| Born to Run Ltd | Extraterritorial | 2012 |
| Boss Vehicle Hire Limited | Administrative & support | 2022 |
| Boston Spa Investments Limited | Financial services | 2019 |
| Boston Spa Property Developments Limited | Real estate | 2018 |
| Botham Wines Limited | Wholesale & retail | 2024 |
| Boundary Watch Straps Ltd | Manufacturing | 2023 |
| Bournbrook Solutions Ltd | Professional & scientific | 2023 |
| Boval Safety and Medical Ltd | Health & social care | 2021 |
| Boviaid Limited | Agriculture & fishing | 2012 |
| Bowe Developments Limited | Construction | 2015 |
| Bowers Construction Limited | Construction | 1978 |
| Bowers Properties (Yorkshire) Ltd | Real estate | 2025 |
| Bowes Green Management Limited | Real estate | 1996 |
| Box Cat Creative Ltd | Information & communication | 2018 |
| Box Consultancy (Yorkshire) Ltd | Professional & scientific | 2022 |
| Box Fast Transport Limited | Transport & logistics | 2019 |
| Box Investment Holdings Limited | Financial services | 2019 |
| Boxy Competitions Ltd | Arts & recreation | 2026 |
| Boyos Tech Limited | Information & communication | 2024 |
| BPE Search Global Limited | Administrative & support | 2024 |
| BPE Search UK Limited | Administrative & support | 2016 |
| BPM Consulting Group Limited | Professional & scientific | 2021 |
| BR Capital Investments Limited | Financial services | 2024 |
| BR Ecom Ltd | Wholesale & retail | 2026 |
| BR1AN Limited | Extraterritorial | 2020 |
| Bracewell Homes Limited | Real estate | 2019 |
| Brackendale House Limited | Real estate | 2025 |