| BB Smiles Limited | Health & social care | 2020 |
| BB8 Holdings Ltd | Real estate | 2017 |
| BBS & Co Ltd | Wholesale & retail | 2013 |
| BCC Twenty Ltd | Real estate | 2024 |
| BD Builders Services Ltd | Construction | 2019 |
| BDL International Holdings Limited | Financial services | 2010 |
| BDN Contracts Ltd | Construction | 2024 |
| BDS Construct Ltd | Construction | 2020 |
| BDS TM Limited | Construction | 2015 |
| Bdtask UK Limited | Construction | 2022 |
| BE on Pointe Ltd | Arts & recreation | 2013 |
| Bealign Ltd | Health & social care | 2024 |
| Beanie Properties Limited | Real estate | 2026 |
| Beanzsoft Limited | Information & communication | 2009 |
| Beargil Ltd | Arts & recreation | 1999 |
| Beatrice Services Limited | Health & social care | 2015 |
| Beauberry Skincare Ltd | Manufacturing | 2024 |
| Beautiful Blue Beauty Limited | Administrative & support | 2024 |
| Beauty Africa Limited | Wholesale & retail | 2017 |
| Beauty Lounge London Ltd | Other services | 2019 |
| Beauty Runway Limited | Other services | 2020 |
| Beauty@Hill LLP | | 2017 |
| BED Bugs Europe Ltd | Health & social care | 2023 |
| BED Bugs in BED Ltd | Health & social care | 2023 |
| BED Bugs International Ltd | Health & social care | 2023 |
| Bedrock Autonomy & Technology Limited | Professional & scientific | 2026 |
| Bedrock Maintenance Limited | Construction | 2016 |
| Beetroot Enterprise Limited | Professional & scientific | 2025 |
| Behind the Brilliance Giving CIC | Education | 2024 |
| Behind the Brilliance Limited | Professional & scientific | 2003 |
| Being Beta Productions Limited | Professional & scientific | 2008 |
| Beirne Haulage Limited | Transport & logistics | 2016 |
| Beirut 24 Ltd | Hospitality | 2023 |
| BEJ Consultants Ltd | Professional & scientific | 2010 |
| Belascos Limited | Wholesale & retail | 2024 |
| Belford and Belford Limited | Real estate | 2015 |
| Belgravia Project Management Limited | Professional & scientific | 2013 |
| Belgravia Properties Ltd | Real estate | 2000 |
| Believe Create Limited | Professional & scientific | 2011 |
| Bellator Family Office Sales and Consultants Ltd | Wholesale & retail | 2024 |
| Bellator Family Office SPV Ltd | Financial services | 2022 |
| Belleza Beauty & Spa Ltd | Administrative & support | 2015 |
| Belluca Ltd | Financial services | 2026 |
| Belmont Properties PVT Ltd | Real estate | 2018 |
| Belmont Youth Limited | Arts & recreation | 2020 |
| Belprop Ltd | Real estate | 2021 |
| BEN Janssens Oriental Art Limited | Wholesale & retail | 1992 |
| Bendev Properties Limited | Real estate | 2005 |
| Benham & Reeves Residential Lettings Limited | Real estate | 2006 |
| Benham and Reeves Limited | Real estate | 1982 |
| Benhams Limited | Real estate | 2018 |
| Benicio Press Ltd | Wholesale & retail | 2023 |
| Benitor Ltd | Construction | 2003 |
| Benoit Limited | Professional & scientific | 2002 |
| Bens Properties Limited | Real estate | 2006 |
| Bereket Oglu Ltd | Wholesale & retail | 2024 |
| Berico Properties Ltd | Real estate | 2022 |
| Beriwal International Limited | Financial services | 2016 |
| Berkshire Drains Holdings Limited | Real estate | 2026 |
| Berkshire Drains Limited | Water & waste | 2012 |
| Berkshire Legal Solutions Ltd | Administrative & support | 2021 |
| Berley Estates Limited | Construction | 1982 |
| Berry & Orchard Properties Ltd | Real estate | 2020 |
| Besa Enterprises Limited | Administrative & support | 2017 |
| Beseen Jewelry Ltd | Wholesale & retail | 2023 |
| Bespoke Intelligence Solutions Limited | Information & communication | 2023 |
| Best Care 4 U Ltd | Health & social care | 2011 |
| Best in One Ltd | Wholesale & retail | 2023 |
| Best Plumb Ltd | Construction | 2015 |
| Bestbasic (One) Limited | Professional & scientific | 2024 |
| Bestbefore Limited | Extraterritorial | 2002 |
| Bestcall Solutions Limited | Professional & scientific | 2017 |
| Bestmemo Limited | Extraterritorial | 2003 |
| BET Design Limited | Information & communication | 2002 |
| Bevan Properties Limited | Real estate | 2019 |
| Bevel & Bond Joinery Ltd | Manufacturing | 2019 |
| Beverage Boys Ltd | Wholesale & retail | 2018 |
| Beverley Drive RTM Company Limited | Households | 2004 |
| Bexley Castles Ltd | Arts & recreation | 2024 |
| BG BIM Solutions Limited | Professional & scientific | 2013 |
| BG T Drylining Ltd | Construction | 2022 |
| BGS Tech Limited | Information & communication | 2015 |
| BGU Building Ltd | Construction | 2024 |
| BHA 1 Limited | Financial services | 2019 |
| BHA 2 Limited | Financial services | 2019 |
| Bhagavan Investments Limited | Real estate | 2025 |
| Bhagavan Property Limited | Real estate | 2020 |
| Bhagavan Trading International Limited | Wholesale & retail | 2017 |
| Bhakti Limited | Extraterritorial | 2020 |
| Bhaman Ltd | Real estate | 2016 |
| Bhavanya IT Solutions Ltd | Information & communication | 2017 |
| Bhavishya Investment Ltd | Real estate | 2012 |
| Bhavya's Beauty Bar Ltd | Other services | 2025 |
| Bhetuwal & Co Ltd | Hospitality | 2025 |
| BHS Security Ltd | Administrative & support | 2019 |
| Bhudia Health Limited | Professional & scientific | 2023 |
| Bhudia Limited | Wholesale & retail | 2004 |
| Bhuruth Engineering Ltd | Manufacturing | 2019 |
| BIA Bora Limited | Wholesale & retail | 2014 |
| Big Heart Fundraising Ltd | Other services | 2022 |