| Booth Ventures Limited | Water & waste | 2004 |
| Booth Ventures Waste (Midlands) Limited | Extraterritorial | 2020 |
| Booth Ventures Waste (North West) Limited | Extraterritorial | 2020 |
| Booth Ventures Waste (Yorkshire) Limited | Extraterritorial | 2020 |
| Bootlegge Liquor Store Limited | Wholesale & retail | 2022 |
| Boova Resources Ltd | Administrative & support | 2025 |
| Booze & Smokes Warrington Ltd | Administrative & support | 2024 |
| Bora Construction Limited | Construction | 2009 |
| Bora Mini Market Ltd | Wholesale & retail | 2025 |
| Border Vending Group Limited | Hospitality | 2007 |
| Border Vending North West Limited | Hospitality | 2007 |
| Bordesley Manor Management Company Limited | Households | 2026 |
| Borntbglobal Limited | Wholesale & retail | 2023 |
| Borosko Ltd. | Arts & recreation | 2017 |
| Borradh Limited | Administrative & support | 2025 |
| Borregaard UK Ltd | Wholesale & retail | 1973 |
| Borshik Ltd | Information & communication | 2024 |
| Boscage Consulting Ltd | Administrative & support | 2023 |
| Bosco Film and TV Entertainment Limited | Information & communication | 2021 |
| Bosley Brook Management Company Limited | Administrative & support | 1997 |
| Boss Barbers Warrington Limited | Other services | 2024 |
| Boss Engineering Limited | Administrative & support | 2011 |
| Boss GAS UK Ltd | Extraterritorial | 2014 |
| Bossmax K9 Services Ltd | Administrative & support | 2019 |
| Bottomley Project Management Limited | Professional & scientific | 2014 |
| Boujee Restaurant and Bar Limited | Hospitality | 2020 |
| Boulton Holding Ltd | Wholesale & retail | 2022 |
| Bounce Back Psychology Limited | Health & social care | 2024 |
| Boux Asthetics and Skin Care Ltd | Other services | 2026 |
| Bow-Saunders Limited | | 1981 |
| Bowden Consulting Ltd | Professional & scientific | 2025 |
| Bowdon Developments North West Ltd | Extraterritorial | 2023 |
| Bower Search Limited | Administrative & support | 2022 |
| Bowes Consulting Services Limited | Professional & scientific | 2020 |
| Bowhart Limited | Real estate | 2016 |
| Bowl 7AR Limited | Hospitality | 2025 |
| Bowland Consulting (Interiors) Ltd | Wholesale & retail | 2021 |
| Bowmas Ltd | Professional & scientific | 2015 |
| Bowshers Dog Ltd | Agriculture & fishing | 2021 |
| Bowtower Limited | Other services | 2017 |
| Bowyers Accountants Limited | Professional & scientific | 2019 |
| Bowyers Limited | Professional & scientific | 2008 |
| Box Analytics & Consulting Ltd | Administrative & support | 2021 |
| Box Arrow Consulting Limited | Information & communication | 2016 |
| Box-It Services Limited | Professional & scientific | 2016 |
| Boxley Associates Limited | Administrative & support | 2009 |
| Boyce's Process & Chemical Commissioning Services Limited | Administrative & support | 2014 |
| Boyd Wilson & Co Limited | Professional & scientific | 2008 |
| Bozova Urfa Ltd | Hospitality | 2025 |
| BP Drivers Ltd | Transport & logistics | 2023 |
| BP Sigma Solutions Limited | Administrative & support | 2008 |
| BP Whites Renovations & Maintenance Ltd | Construction | 2022 |
| BPL Projects Limited | Information & communication | 2010 |
| BPM Water Limited | Administrative & support | 2024 |
| Bpmc Limited | Administrative & support | 2015 |
| BR Carriers Limited | Transport & logistics | 2014 |
| BR Plumbing and Heating Limited | Construction | 2022 |
| Brabbi Ltd | Administrative & support | 2020 |
| Brabbi Property Maintenance Ltd | Construction | 2020 |
| Brabco 1601 Limited | Professional & scientific | 2016 |
| Brack OPS Consultancy Limited | Information & communication | 2022 |
| Brackendene Studio Limited | Professional & scientific | 2022 |
| Brackenfield Consultancy Limited | Construction | 2023 |
| Bracon Engineering Limited | Administrative & support | 2007 |
| Bradkeinz | Financial services | 2022 |
| Bradley Consulting Group Limited | Administrative & support | 2022 |
| Bradley K Morris Ltd | Construction | 2026 |
| Bradley Williams Engineering Ltd | Professional & scientific | 2019 |
| Bradshaw Cars Ltd | Wholesale & retail | 2011 |
| Bradshaw Property Developments Limited | Real estate | 2006 |
| Bradshaw Property Investments Limited | Real estate | 2006 |
| Braemac Limited | Wholesale & retail | 1998 |
| Braemore Consulting Ltd | Professional & scientific | 2014 |
| Braeside NW Limited | Real estate | 2022 |
| Braid Hills Limited | Professional & scientific | 2002 |
| Braidlock Limited | Manufacturing | 2004 |
| Brailsford Mechanical Limited | Professional & scientific | 2016 |
| Braken Limited | Professional & scientific | 2011 |
| Bram Enterprises Limited | Manufacturing | 2019 |
| Bramall Property Developers Ltd | Manufacturing | 2020 |
| Bramble Partners Limited | Professional & scientific | 2022 |
| Bramley Testing Limited | Professional & scientific | 2019 |
| Bramwin Limited | Financial services | 2025 |
| Brancabar Limited | Financial services | 2025 |
| Brancaster Care Homes Limited | Health & social care | 2005 |
| Branch Masters Limited | Administrative & support | 2025 |
| Branch Tech Recruitment Limited | Administrative & support | 2019 |
| Branches Process Tech Ltd | Information & communication | 2025 |
| Brand Championship Ltd | Information & communication | 2011 |
| Brand Folk Ltd | Professional & scientific | 2019 |
| Brandify Connect Ltd | Professional & scientific | 2023 |
| Brandlesholme (Property Management) Company Limited | Real estate | 2018 |
| Brandon Wheels Knutsford Ltd | Wholesale & retail | 2024 |
| Brands Group Trading Limited | Wholesale & retail | 2018 |
| Brandt ERP Consulting Ltd | Administrative & support | 2011 |
| Branston Engineering Solutions Limited | Administrative & support | 2024 |
| Brasstoff Limited | Administrative & support | 2004 |
| Bratu A&C Ltd | Transport & logistics | 2024 |
| Brazilian Joinery Limited | Manufacturing | 2011 |
| Brcjc Consulting Ltd | Information & communication | 2025 |