| Blank Viral Ltd | Professional & scientific | 2024 |
| Blankstone Sington Limited | Financial services | 1989 |
| Blaq Chic Ltd | Wholesale & retail | 2021 |
| Blaq Properties Ltd | Real estate | 2024 |
| Blarsen Sols Limited | Information & communication | 2026 |
| Blasch Consultancy Limited | Professional & scientific | 2024 |
| Blast and Pressure Cleaning Limited | Extraterritorial | 2025 |
| Blast Equipment Limited | Professional & scientific | 1982 |
| Blast Nation Ltd | Administrative & support | 2025 |
| Blatch Consulting Limited | Professional & scientific | 2008 |
| Blaue Zonen Ltd | Administrative & support | 2024 |
| Blaukerth Ltd | Transport & logistics | 2020 |
| Blaze Bayley Recording Ltd | Arts & recreation | 2018 |
| Blaze FM Ltd | Administrative & support | 2022 |
| Blaze Marketing Limited | Professional & scientific | 2013 |
| Blaze Path Ventures Limited | Wholesale & retail | 2025 |
| Blazeforge Capital Ltd | Extraterritorial | 2025 |
| Blazenest Capital Ltd | Extraterritorial | 2025 |
| Blazenova Trading Partners Ltd | Extraterritorial | 2025 |
| Blazespark Trading Solutions Ltd | Extraterritorial | 2025 |
| Blazetech Ltd | Construction | 2023 |
| Blazewood Ltd | Wholesale & retail | 2007 |
| Blazing IT Limited | Wholesale & retail | 2025 |
| Blazon Technologies Ltd | Information & communication | 2020 |
| BLB Partners LLP | | 2016 |
| BLB Rural Ltd | Real estate | 2026 |
| BLC Charlestown Construction Ltd | Construction | 2017 |
| BLC Construction Ltd | Construction | 2024 |
| BLC NO1 Limited | Financial services | 2014 |
| BLC Reservoir Ltd | Real estate | 2020 |
| Blck Media Group Limited | Information & communication | 2016 |
| Blck Productions CIC | Information & communication | 2025 |
| BLD Technology Ltd | Manufacturing | 2018 |
| Bleach Studios Ltd | Wholesale & retail | 2025 |
| Bleak House Media Ltd | Information & communication | 2025 |
| Bleasdale Travel Ltd | Administrative & support | 2025 |
| BLEEP24 Healthcare Ltd | Health & social care | 2020 |
| Blend & More Ltd | Hospitality | 2023 |
| Blended Wine Consultancy Ltd | Other services | 2023 |
| Blenkie Limited | Financial services | 2013 |
| Bleo Consulting Ltd | Professional & scientific | 2021 |
| Bless Enterprises Ltd | Real estate | 2014 |
| Blessed Care Consultancy Ltd | Health & social care | 2020 |
| Blessed David Limited | Information & communication | 2015 |
| Blessed Deals Ltd | Wholesale & retail | 2024 |
| Blessed Healthcare Ltd | Other services | 2017 |
| Blessed Kids Ltd | Health & social care | 2020 |
| Blessed Occasions Limited | Wholesale & retail | 2023 |
| BLESSEDHOPE4U Ltd | Health & social care | 2022 |
| Blessgain Limited | Real estate | 1994 |
| Blessing E Mart Limited | Wholesale & retail | 2025 |
| Blessing Trading Company Ltd | Wholesale & retail | 2025 |
| Blessing Travel Limited | Administrative & support | 2016 |
| Blesswills Properties Ltd | Real estate | 2026 |
| Blessy Services Ltd | Professional & scientific | 2025 |
| Blether Forever C.I.C. | Arts & recreation | 2025 |
| Bleu Carter Ltd | Hospitality | 2025 |
| Bleuprnt Ltd | Wholesale & retail | 2023 |
| Blexo Ltd | Wholesale & retail | 2026 |
| Blezard Courier Services Limited | Transport & logistics | 2026 |
| Blighty Consultants Ltd | Wholesale & retail | 2015 |
| Blindfold Limited | Wholesale & retail | 2018 |
| Blinding 0121 Acquisitions Limited | Real estate | 2023 |
| Blinding 0121 Acquisitions SPV1 Ltd | Real estate | 2024 |
| Blinds & Decor Ltd | Wholesale & retail | 2024 |
| Blinds Cloud Ltd | Information & communication | 2026 |
| Blinds Factory Limited | Construction | 2025 |
| Bling Home Decor Ltd | Wholesale & retail | 2021 |
| Bling N Gems Ltd | Wholesale & retail | 2015 |
| Bling Shine Cleaning Services Ltd | Other services | 2025 |
| Blink Finance Limited | Professional & scientific | 2017 |
| Blink Money Limited | Professional & scientific | 2017 |
| Blink Optimise Limited | Administrative & support | 2022 |
| Blinkers Cleaning Services Limited | Administrative & support | 2025 |
| Blinkhorn Properties Ltd | Real estate | 2025 |
| Blinktok Ltd | Information & communication | 2025 |
| Bliss Gifts Ltd | Manufacturing | 2024 |
| Bliss Rain Prints Limited | Manufacturing | 2020 |
| Bliss Wholesale Limited | Wholesale & retail | 2022 |
| Blissful Essence Ltd | Manufacturing | 2020 |
| Blissful Horizons Capital Ltd | Extraterritorial | 2025 |
| Blissfulbites Ltd | Hospitality | 2023 |
| Blissfulbloombeauty Limited | Wholesale & retail | 2024 |
| Blisslaserstudio Ltd | Other services | 2025 |
| Blitz Promotions Limited | Professional & scientific | 2023 |
| Blitzmail Highlight Ltd | Administrative & support | 2023 |
| Blizomart Ltd | Transport & logistics | 2025 |
| BLN Consultants Limited | Professional & scientific | 2015 |
| BLN.NO.1 Properties Ltd | Real estate | 2026 |
| Bloc North Ltd | Information & communication | 2022 |
| Bloch AI Ltd | Professional & scientific | 2024 |
| Block 4 CW (LUV) Limited | Financial services | 2025 |
| Block B Films Ltd | Information & communication | 2025 |
| Block Digital Ltd | Administrative & support | 2017 |
| Block Investments NE Ltd | Real estate | 2019 |
| Blockaid (North West) Ltd | Construction | 2004 |
| Blockbuster Pizza Ltd | Hospitality | 2025 |
| Blockchain Core Accountants Ltd | Professional & scientific | 2021 |
| Blockchain Video Production Limited | Information & communication | 2018 |
| Blockchainomatic Limited | Wholesale & retail | 2021 |