| Barcode Products Ltd | Administrative & support | 2015 |
| Bargleton Ltd | Professional & scientific | 2022 |
| Barkers Joinery Limited | Construction | 2010 |
| Bart Garage Ltd | Wholesale & retail | 2022 |
| Batched Limited | Manufacturing | 2017 |
| Baxcrown Limited | Construction | 1986 |
| Bayly's Auto Body Repair Ltd | Wholesale & retail | 2025 |
| BCO Building & Construction Limited | Construction | 2022 |
| BE U Bela Ltd | Real estate | 2019 |
| Beagle 45 Ltd | Construction | 2026 |
| Beaky Leisure Limited | Hospitality | 2017 |
| Bearcat Enterprise Ltd | Construction | 2025 |
| Beaspoke Design Studio Ltd | Professional & scientific | 2025 |
| Beaver and Macaw Consulting LLP | | 2021 |
| Beckon Limited | Professional & scientific | 2022 |
| BEE Helps Ltd | Health & social care | 2023 |
| Beechwood Bespoke Carpentry Ltd | Construction | 2021 |
| Beechwood Horse Transport Limited | Transport & logistics | 2025 |
| Beechwood Property Management Services Limited | Real estate | 2020 |
| Bell Studio Limited | Professional & scientific | 2017 |
| Belmont MFO Limited | Professional & scientific | 2025 |
| BEN ARI Limited | Professional & scientific | 2016 |
| BEN Darius Limited | Professional & scientific | 2000 |
| BEN Elvin Planning Consultancy Limited | Professional & scientific | 2017 |
| BEN Legg Joinery Ltd | Manufacturing | 2019 |
| Benjamin Burrows & Co Limited | Professional & scientific | 2026 |
| Berg-Davies Associates Ltd | Professional & scientific | 2011 |
| Bernache Leadership Limited | Education | 2019 |
| Best Deals Ever Ltd | Wholesale & retail | 2024 |
| Betsy Rowlands Tuition Limited | Education | 2020 |
| Better Conversation Limited | Professional & scientific | 2017 |
| BGV Solutions Limited | Professional & scientific | 2009 |
| BIN Boys East Anglia Ltd | Administrative & support | 2025 |
| Bindaco Limited | Information & communication | 2025 |
| Bio-Medical Science & Technology UK Limited | Financial services | 2024 |
| Birdbox Media Marketing Limited | Administrative & support | 2013 |
| Birth Solutions Ltd | Health & social care | 2023 |
| Bishop & Miller Auctioneers Limited | Wholesale & retail | 2014 |
| Bite Boost Ltd | Hospitality | 2023 |
| Bjbc Limited | Construction | 2022 |
| BJP Retail Services Limited | Wholesale & retail | 2012 |
| Blessedbile Ltd | Health & social care | 2022 |
| Block 4 Esplanade Court RTM Company Ltd | Households | 2020 |
| Block Marketing Limited | Professional & scientific | 2024 |
| Bloomsmore Limited | Wholesale & retail | 2015 |
| Blue Earth Consulting Limited | Professional & scientific | 2019 |
| Blue Lion Global UK Ltd | Professional & scientific | 2023 |
| Blue Star Human Resources Limited | Administrative & support | 2003 |
| BM Automotive Ltd | Wholesale & retail | 2025 |
| BMF Renewables Ltd | Manufacturing | 2024 |
| Boba B Housing Limited | Real estate | 2021 |
| Bodywize Ltd | Arts & recreation | 2012 |
| Bolthole Consult Ltd | Construction | 2018 |
| Bonitas Wholefoods Ltd | Wholesale & retail | 2020 |
| Bonkers Beachwear Ltd | Wholesale & retail | 2025 |
| Boss Burger Stowmarket Ltd | Hospitality | 2025 |
| Boundary Kennels & Training Limited | Other services | 2013 |
| Bournebridge Property Investments Ltd | Hospitality | 2024 |
| Bowmans Dents Limited | Wholesale & retail | 2006 |
| Bowmen Properties Limited | Real estate | 2015 |
| Boxandtutt Ltd | Hospitality | 2024 |
| Boydell Holdings Limited | Financial services | 2022 |
| Boyton Bulk Haulage Limited | Transport & logistics | 2009 |
| Boyton Services Limited | Transport & logistics | 1999 |
| BPS Property Investments Limited | Real estate | 2021 |
| Bramley Medical Limited | Health & social care | 2018 |
| Brand Cartel Limited | Professional & scientific | 2016 |
| Brazier Tiling Ltd | Construction | 2016 |
| Breathing Space Norfolk Limited | Hospitality | 2011 |
| Brett Design Partnership Limited | Professional & scientific | 2017 |
| Brew & Grind Ltd | Wholesale & retail | 2023 |
| Brian Palmer Haulage Ltd | Transport & logistics | 2015 |
| Brian Palmer Holdings Ltd | Financial services | 2023 |
| Bridal Shop Ltd | Wholesale & retail | 2010 |
| Bridge Place Autos Limited | Wholesale & retail | 2000 |
| Brightside Wealth Management Limited | Financial services | 2019 |
| Brite Intelligence Ltd | Professional & scientific | 2025 |
| Britesparx Limited | Information & communication | 2011 |
| Broadacre Projects Limited | Construction | 2021 |
| Broadacre Properties Limited | Real estate | 2024 |
| Broadhurst Electrical Limited | Extraterritorial | 2018 |
| Brockford Consulting Limited | Information & communication | 2014 |
| Broker Business Systems Limited | Information & communication | 2003 |
| Broughton Hall Dairy Limited | Manufacturing | 2022 |
| Browne Property Investments Limited | Real estate | 2026 |
| Brufords Ltd | Hospitality | 2024 |
| Brycotrain Ltd | Information & communication | 2010 |
| Bshatta Limited | Health & social care | 2016 |
| Bshc Contractors Ltd | Construction | 2025 |
| BTN Healthcare Ltd | Health & social care | 2019 |
| Buck Asset Group Ltd | Financial services | 2025 |
| Build to Plans Partnership Limited | Professional & scientific | 2012 |
| Buildright Suffolk Limited | Construction | 2014 |
| Burghouse Ltd | Construction | 2005 |
| Bury Road (2017) Management Company Limited | Households | 2017 |
| Bury ST Edmunds Osteopaths Limited | Health & social care | 2008 |
| Business Vitamins UK Limited | Professional & scientific | 2006 |
| Bussey Windows Group Ltd | Manufacturing | 2025 |
| Butel Pathology Limited | Health & social care | 2021 |
| Butterfly London Group Limited | Financial services | 2016 |