| Biro ITN Limited | Marlow | 2019 |
| BIRO3 Limited | Harrow | 2026 |
| Birona Limited | Colyton | 2013 |
| Birrell Holdings Limited | London | 2025 |
| Birrell Risks & Co Ltd | Lutterworth | 2026 |
| Birsay Holding Ltd | London | 2018 |
| Birstall Care Holdings Limited | London | 2018 |
| BIRSTWITH123 Limited | Leeds | 2017 |
| Birtles Computing Company Ltd | Derby | 2024 |
| Birtles Parkland Ltd | Manchester | 2025 |
| Birtley Investment Limited | Wimborne | 2023 |
| Birtwhistle Holdings Limited | Huddersfield | 2020 |
| Birtwistle Properties Ltd | Knutsford | 2018 |
| BIS (Postal Services ACT 2011) Company Limited | London | 2012 |
| Bisaggio Holdings Ltd | Batley | 2023 |
| Bisak Ltd | London | 2022 |
| Bisca North Yorkshire Limited | Helmsley | 2017 |
| Biscayne Projects Limited | London | 2024 |
| Bischof Trading Group Limited | London | 2020 |
| Bischoff (Holdings) Limited | Gillingham | 2019 |
| Biscoff Property Holdco Limited | Welwyn Garden City | 2021 |
| Biscuit TIN Investments Limited | Gloucester | 2025 |
| Biscuit Vehicle Leasing Limited | Chester Le Street | 2008 |
| Bisg Ltd | Ruislip | 2026 |
| Bisgin Group Ltd | London | 2026 |
| Bish Holdings Limited | London | 2021 |
| Bishop & Associates Holdings Ltd. | Isleworth | 2013 |
| Bishop & Bishop Estates Ltd | Southampton | 2024 |
| Bishop & Company (MSN) Limited | Bristol | 2017 |
| Bishop Calway Insurance Services Limited | Hove | 2002 |
| Bishop Capital Limited | Eastbourne | 2023 |
| Bishop Enterprises Limited | Enfield | 2019 |
| Bishop Health Ltd | Billingham | 2023 |
| Bishop Holdings Limited | Sutton Coldfield | 2025 |
| Bishop Investment Group Ltd | Sawbridgeworth | 2026 |
| Bishop Mezz Holdco Limited | Bradford | 2026 |
| Bishop Mezzco Limited | Bradford | 2026 |
| Bishop Mortgages Limited | Chesterfield | 2013 |
| Bishop Propco Limited | Bradford | 2026 |
| Bishop Rock Partners Holdings Limited | London | 2023 |
| Bishop Senior Holdco Limited | Bradford | 2026 |
| Bishop Skinner Acquisitions Limited | London | 2005 |
| Bishop Skinner Insurance Brokers Limited | London | 1973 |
| Bishop UK Holdings Ltd | Walsall | 2023 |
| Bishop Wood Holdings Limited | Radcliffe | 2006 |
| Bishop Works Limited | Redruth | 2025 |
| Bishop's Glen Investment Partners Limited | Cairndow | 2022 |
| Bishopgate Limited | Liverpool | 2003 |
| Bishopgate Mortgage Services Limited | Mannings Heath | 2019 |
| Bishops and Clerks Ltd | Tunbridge Wells | 2025 |
| Bishops Financial Planning Limited | Blackburn | 2015 |
| Bishops Financial Services Limited | Lymington | 1986 |
| Bishops Management Limited | Harrow | 1997 |
| Bishopscourt Financial Holdings Limited | Brentwood | 1984 |
| Bishopsgate Advances Limited | Chester | 2004 |
| Bishopsgate Corporate Finance Limited | Stamford | 1977 |
| Bishopsgate Funding Ltd | Manchester | 1999 |
| Bishopsgate Holdings Limited | Stamford | 2024 |
| Bishopsgate INS Group Ltd | Welwyn Garden City | 2026 |
| Bishopsgate Insurance Brokers Limited | London | 1918 |
| Bishopsgate Nominees Limited | Norwich | 2019 |
| Bishopsgate Wealth and Investment Management Limited | London | 2016 |
| Bishopsrock Holdings Limited | Bolton | 2025 |
| Bishopsrock Investment Holdings Limited | Bolton | 2025 |
| Bishopstone Homes Ltd | Newton Abbot | 2023 |
| Bishopton Glade Ltd | Ripon | 2026 |
| Bishwan Ltd | Harrow | 2018 |
| Bisichi Mining Management Services Limited | London | 2005 |
| Bisichi Resources Limited | London | 2025 |
| Bisila Limited | London | 2018 |
| Bisley Group Holdings Limited | Bisley | 2024 |
| Bisley House Bar and Restaurant Ltd | Bristol | 2025 |
| Bisley Solar Limited | London | 2020 |
| Bismillah 786 Holdings Ltd | Nottingham | 2021 |
| Bismillah Personal Holdings Limited | Blackburn | 2021 |
| Bison Assist Group Limited | Castleford | 2020 |
| Bison Feeder Limited | London | 2025 |
| Bison Group Holdings Ltd | Loughborough | 2025 |
| Bison Holdings Limited | Barnsley | 2019 |
| Bison IBC Holding Limited | Mansfield | 2026 |
| Bison Investments Limited | Hinckley | 2019 |
| Bison Machinery Holdings Ltd | Stafford | 2024 |
| Bison Storage Holdings Limited | Dewsbury | 2020 |
| Bison Wealth Management Ltd | London | 2026 |
| Bispo Limited | Plymouth | 2023 |
| Biss Underwriting Limited | Newcastle Upon Tyne | 2010 |
| Bissan & Alhindi Holdings Limited | London | 2023 |
| Bissap Holdings Limited | London | 2022 |
| Bissell & Partners Limited | Wymondham | 2012 |
| Bissell Holdings Ltd | Swadlincote | 2021 |
| Bisson International Holdings Limited | Bristol | 2021 |
| Bisterne Farms Holdings Limited | Bournemouth | 2016 |
| Bistro 1 Frith ST. Limited | London | 2009 |
| Bistro Bombay Ltd | Bolton | 2025 |
| Bistro Ventures Limited | Goole | 2026 |
| Bistrohq Limited | Macclesfield | 2015 |
| BIT Estate & Trade Solutions Ltd | London | 2025 |
| BIT Evolution Network Limited | London | 2026 |
| BIT Exchange Ltd | Arundel | 2021 |
| BIT Performance Ltd | London | 2020 |