| BSE 2.7 Ltd | Real estate | 2024 |
| BSE 2.8 Ltd | Real estate | 2024 |
| BSE 2.9 Ltd | Real estate | 2024 |
| BSE 3.6 Ltd | Real estate | 2019 |
| BSE 3.7 Ltd | Real estate | 2019 |
| BSE 3.8 Ltd | Real estate | 2019 |
| BSE 3.9 Ltd | Real estate | 2019 |
| BSE 4.6 Ltd | Real estate | 2024 |
| BSE 4.7 Ltd | Real estate | 2024 |
| BSE 4.8 Ltd | Real estate | 2024 |
| BSE 4.9 Ltd | Real estate | 2024 |
| BSE 6 Ltd | Real estate | 2025 |
| BSE 6.0 Ltd | Real estate | 2024 |
| BSE 6.1 Ltd | Real estate | 2025 |
| BSE 6.2 Ltd | Real estate | 2025 |
| BSE 6.3 Ltd | Real estate | 2025 |
| BSE 6.4 Ltd | Real estate | 2025 |
| BSE 6.5 Ltd | Real estate | 2025 |
| BSE 6.6 Ltd | Real estate | 2025 |
| BSE 6.7 Ltd | Real estate | 2025 |
| BSE 6.8 Ltd | Real estate | 2025 |
| BSE 6.9 Ltd | Real estate | 2025 |
| BSE2.1 Ltd | Real estate | 2017 |
| BSE2.2 Ltd | Real estate | 2017 |
| BSE2.3 Ltd | Real estate | 2017 |
| BSE3 Ltd | Real estate | 2017 |
| BSE3.1 Ltd | Real estate | 2017 |
| BSE3.2 Ltd | Real estate | 2017 |
| BSE3.3 Ltd | Real estate | 2017 |
| BSE3.4 Ltd | Real estate | 2017 |
| BSE3.5 Ltd | Real estate | 2017 |
| BSE4 Ltd | Real estate | 2019 |
| BSE4.1 Ltd | Real estate | 2019 |
| BSE4.2 Ltd | Real estate | 2019 |
| BSE4.3 Ltd | Real estate | 2019 |
| BSE4.4 Ltd | Real estate | 2019 |
| BSE4.5 Ltd | Real estate | 2019 |
| BSE5 Ltd | Real estate | 2021 |
| BSE5.1 Ltd | Real estate | 2021 |
| BSE5.2 Ltd | Real estate | 2021 |
| BSE5.3 Ltd | Real estate | 2021 |
| BSE5.4 Ltd | Real estate | 2021 |
| BSE5.5 Ltd | Real estate | 2021 |
| BSE5.6 Ltd | Real estate | 2022 |
| BSE5.7 Ltd | Real estate | 2022 |
| BSE5.8 Ltd | Real estate | 2022 |
| BSE5.9 Ltd | Real estate | 2022 |
| BSG Property Investments Ltd | Real estate | 2021 |
| BSK Entertainment Ltd | Arts & recreation | 2022 |
| BSM Legacy UK Limited | Real estate | 2023 |
| BSP Contractors Ltd | Construction | 2019 |
| Bsqa Limited | Professional & scientific | 2013 |
| Bsquare International Ltd | Wholesale & retail | 2025 |
| BSR Care Ltd | Health & social care | 2024 |
| BSV Constructions Limited | Construction | 2019 |
| BSV Developments Limited | Construction | 2024 |
| BSV Investments Limited | Real estate | 2005 |
| BT Global Couriers Ltd | Transport & logistics | 2025 |
| Btaa Ltd | Professional & scientific | 2009 |
| Btenterprises Ltd | Wholesale & retail | 2025 |
| BTF Brickwork Ltd | Construction | 2023 |
| BTL Investments Limited | Real estate | 2002 |
| BTN FM Limited | Other services | 2024 |
| BTP Advisers Limited | Professional & scientific | 2020 |
| BTS Property Management Ltd | Real estate | 2023 |
| Bubble & Blend Ltd | Other services | 2021 |
| Bubble G Limited | Manufacturing | 2021 |
| Bubbles E6 Ltd | Wholesale & retail | 2020 |
| Bubbles Forever Properties Ltd | Real estate | 2025 |
| Bubblin Records Ltd | Arts & recreation | 2023 |
| Buchanan Kerr Limited | Arts & recreation | 1970 |
| Buckingham Court Residents Management Limited | Administrative & support | 1969 |
| Buckingham Tailors Ltd | Other services | 2018 |
| Buckitup Ltd | Wholesale & retail | 2025 |
| Bucorvus Limited | Wholesale & retail | 2025 |
| Buddi's Food Flavours Ltd. | Hospitality | 2024 |
| Budget Car Rental Ltd | Wholesale & retail | 2022 |
| Budget Finds CIC | Wholesale & retail | 2026 |
| Budget Services Ltd | Administrative & support | 2019 |
| Budget World Ltd | Wholesale & retail | 2022 |
| Budgetlane Ltd | Wholesale & retail | 2024 |
| Budhil Limited | Information & communication | 2014 |
| Budunkaylu Services Ltd | Real estate | 2018 |
| Buella Limited | Construction | 2020 |
| BUG Eyed Studios Ltd | Arts & recreation | 2026 |
| Bugfree Solutions Ltd | Information & communication | 2024 |
| BUHALTER4U Limited | Professional & scientific | 2024 |
| Buhalterija UK Ltd | Professional & scientific | 2014 |
| BUHUS88 Ltd Ltd | Transport & logistics | 2025 |
| Builco Ltd | Real estate | 2023 |
| Build & Repair Ltd | Construction | 2026 |
| Build 2020 Limited | Real estate | 2020 |
| Build Build Build Ltd | Construction | 2018 |
| Build HUT Construction Limited | Construction | 2024 |
| Build Kwik Ltd | Construction | 2023 |
| Build London Atoz Limited | Other services | 2019 |
| Build Number 8 Ltd | Construction | 2013 |
| Build Renovate Manage Ltd | Construction | 2022 |
| Build Skills Limited | Construction | 2023 |
| Build the Fast Ltd | Construction | 2023 |