| BUK Barbers Limited | Other services | 2026 |
| BUL Corp Limited | Construction | 2012 |
| Bulbul Properties Ltd | Real estate | 2025 |
| Bulemia Ltd | Wholesale & retail | 2023 |
| Bull Bars Ltd | Hospitality | 2019 |
| Bull INS Group Ltd | Construction | 2024 |
| Bulldog Vintage Ltd | Wholesale & retail | 2018 |
| Bulls and Tailor Ltd | Wholesale & retail | 2020 |
| Bullsmoor Dental Practice Limited | Health & social care | 2010 |
| Buluskatech Solutions Ltd | Wholesale & retail | 2025 |
| Bulut Cafe Ltd | Hospitality | 2023 |
| Bumzy’S Creative Cakes Ltd | Manufacturing | 2023 |
| Burac Construction Ltd | Construction | 2024 |
| Burak.Consultancy Limited | Financial services | 2025 |
| Buraqe Limited | Administrative & support | 2025 |
| Burco Plumbing and GAS Ltd | Construction | 2023 |
| Burger Boyzgh Limited | Hospitality | 2023 |
| Burlington House RTM Company Ltd | Households | 2021 |
| Burnham & Burke Limited | Construction | 2023 |
| Burnham Technical Services Limited | Manufacturing | 2007 |
| Busege Limited | Wholesale & retail | 2020 |
| Bushfire Limited | Manufacturing | 1995 |
| Business Assist Plus Limited | Professional & scientific | 2017 |
| Butkas Recovery Ltd | Wholesale & retail | 2025 |
| Butlers Court Residents Management Company Limited | Professional & scientific | 2010 |
| Butterfly Moon Ltd | Information & communication | 2006 |
| Butterfly Queen Beauty Shop Ltd | Wholesale & retail | 2022 |
| BUYEAZY555 Ltd | Wholesale & retail | 2026 |
| Buyro London Limited | Wholesale & retail | 2025 |
| Buzz Media Group Limited | Administrative & support | 2020 |
| Buzz Monkey Limited | Financial services | 2017 |
| Buzz Test Ltd | Information & communication | 2014 |
| BV Gardening Ltd | Administrative & support | 2018 |
| Bwise Digital Limited | Information & communication | 2017 |
| BY ANY Means Limited | Arts & recreation | 2024 |
| BY Cafe Limited | Hospitality | 2025 |
| BY Grace Etmlj Care Limited | Health & social care | 2025 |
| BY Joja Ltd | Hospitality | 2023 |
| BY the Books Financial Services Limited | Professional & scientific | 2025 |
| Byberfin Aesthetics Ltd | Other services | 2026 |
| Bycullah (Enfield) Management Company Limited | Households | 1988 |
| Bycullah Court Management Company Limited | Households | 2002 |
| Byexample Ltd | Wholesale & retail | 2025 |
| Byron & Byron Holdings Limited | Real estate | 2005 |
| Byron & Byron Limited | Manufacturing | 1988 |
| Byrsa Ltd | Information & communication | 2025 |
| Byte ME Tech Solutions Ltd | Information & communication | 2025 |
| B’S Spice Heaven Limited | Wholesale & retail | 2024 |
| C & C Solak Limited | Real estate | 2022 |
| C & R Tool Hire Ltd. | Administrative & support | 1997 |
| C & T Look Limited | Information & communication | 2009 |
| C a Electrics Limited | Construction | 2017 |
| C G Walters Consulting Ltd | Health & social care | 2018 |
| C I London & Southend Ltd | Wholesale & retail | 2019 |
| C Jenkin Heating & Plumbing Limited | Construction | 2025 |
| C L Heating Express Limited | Manufacturing | 2019 |
| C R Harrower Limited | Wholesale & retail | 2006 |
| C S G (Ushers) Limited | Administrative & support | 2008 |
| C T S Building Solutions Limited | Construction | 2008 |
| C V T Services Limited | Manufacturing | 2022 |
| C&A Delivery Ltd | Transport & logistics | 2020 |
| C&A Shine Limited | Administrative & support | 2024 |
| C&Al Construction Ltd | Construction | 2026 |
| C&C Building and Development Ltd | Construction | 2022 |
| C&C Invest Ltd | Construction | 2019 |
| C&Ca Construction & Building Supplies Limited | Manufacturing | 2025 |
| C&Dw General Contractors Ltd | Construction | 2020 |
| C&E Lambs Ltd | Wholesale & retail | 2025 |
| C&K Accountant Ltd | Professional & scientific | 2022 |
| C&K Nails Limited | Other services | 2020 |
| C&L Noble Property Investment Ltd | Real estate | 2021 |
| C&M Construction Ltd | Construction | 2014 |
| C&M Oakridge Properties Ltd | Real estate | 2026 |
| C&M Roofing Contractors Ltd | Construction | 2016 |
| C&N Estate Agents Limited | Real estate | 2016 |
| C&P Maintenance Ltd | Construction | 2026 |
| C&Y Taylor UK Ltd | Professional & scientific | 2007 |
| C. and S. Mccarthy Limited | Transport & logistics | 1985 |
| C.P Barbers Ltd | Other services | 2026 |
| C.R. Electrical Company Limited | Construction | 1976 |
| C.Y.G Site Catering Ltd | Hospitality | 2024 |
| C2S Storage Limited | Transport & logistics | 2026 |
| C9 Kitchen Ltd | Hospitality | 2025 |
| CA Andor Limited | Construction | 2016 |
| CA Events Mgmt Ltd | Arts & recreation | 2025 |
| CA PHE Sang Limited | Other services | 2024 |
| CAA Services Ltd | Health & social care | 2016 |
| Caaveri Ltd | Wholesale & retail | 2007 |
| Caaveri Wholesale Ltd | Wholesale & retail | 2020 |
| Cable Plus Limited | Wholesale & retail | 2017 |
| Caci Property Solutions Ltd | Real estate | 2025 |
| CAD Building Ltd | Construction | 2015 |
| Cadde IT Solutions Ltd | Information & communication | 2022 |
| Cadogan Homes (Herts) Limited | Construction | 2006 |
| CADWISE247 Ltd | Professional & scientific | 2025 |
| Caesar Group Ltd | Manufacturing | 2021 |
| Caesarstone (UK) Ltd | Manufacturing | 2005 |
| Cafe Nadia Ltd | Hospitality | 2025 |
| Cages Investments Limited | Real estate | 2024 |
| Cagiran Properties Limited | Real estate | 2020 |