| Bridgetech Industries Limited | Information & communication | 2015 |
| Bright MED Ltd | Professional & scientific | 2025 |
| Brighthouse Photography Limited | Professional & scientific | 2012 |
| Brinsworth Close Residents Association Limited | Households | 1959 |
| British Group Ltd | Manufacturing | 2025 |
| Broad Bridge Estates Limited | Real estate | 2020 |
| Broden.Ai Ltd | Professional & scientific | 2024 |
| Brook Associates Limited | Professional & scientific | 2000 |
| Brook Court Brentford (Freehold) Ltd | Real estate | 2022 |
| Brook House (Twickenham) Limited | Households | 2001 |
| Brook Road (Brentford) Residents Association Limited | Households | 1986 |
| Brookstone Roofing and Building Ltd | Construction | 2025 |
| Brosna Consulting Limited | Professional & scientific | 2014 |
| Brown Global Group Ltd | Wholesale & retail | 2016 |
| BSB Construction Services Limited | Professional & scientific | 2021 |
| BT Flooring Services Ltd | Construction | 2017 |
| BT Wood Flooring Services Ltd | Construction | 2023 |
| Btbb Ltd. | Education | 2024 |
| Bucklands Road Residents Association Limited | Households | 1989 |
| Buds Office Plants Limited | Administrative & support | 2013 |
| Buka Ltd. | Arts & recreation | 2015 |
| Bukit Ceylon Consulting Limited | Information & communication | 2023 |
| Bulang Limited | Information & communication | 2018 |
| Bull in a China Shop Ltd | Information & communication | 2016 |
| Bunnywell (Guildford) Ltd | Construction | 2020 |
| Bunnywell (ST Albans) Ltd | Construction | 2024 |
| Bunnywell Holdings Ltd | Real estate | 2020 |
| Buona Causa Limited | Real estate | 2022 |
| Burnell House Development Limited | Construction | 2017 |
| Burnum Group Ltd | Real estate | 2022 |
| Bushy Court (Hampton Wick) Limited | Households | 2008 |
| Business Accomplish Limited | Professional & scientific | 2006 |
| Business Car Manager Limited | Information & communication | 2005 |
| Business Enabling Services Limited | Administrative & support | 2014 |
| Button Monkey Limited | Information & communication | 2008 |
| Buzon (UK) Limited | Wholesale & retail | 2006 |
| Buzzer & Co Ltd | Other services | 2022 |
| Bwkw Fitness Ltd | Arts & recreation | 2025 |
| Bwkw Ltd | Information & communication | 2022 |
| BX Property Ltd | Construction | 2014 |
| C J Property Investments Ltd | Construction | 2011 |
| C2S Media Ltd | Information & communication | 2019 |
| C4+9 Holdings Limited | Administrative & support | 2007 |
| C4G Cycling CIC | Other services | 2025 |
| Cadenza Creations Limited | Administrative & support | 2010 |
| Caffell Tutoring Services Ltd | Education | 2013 |
| Caine Hendy Consulting Limited | Professional & scientific | 2022 |
| Calibre Collection Limited | Wholesale & retail | 2022 |
| Cambia Consultant Limited | Professional & scientific | 2026 |
| Camera Creations Limited | Information & communication | 2012 |
| Candid Finance Limited | Financial services | 2021 |
| Canewebbing Ltd | Wholesale & retail | 2021 |
| Cannon Accounting Limited | Professional & scientific | 2023 |
| Canoe Club (Freehold) Limited | Arts & recreation | 1931 |
| Caper Clothing Ltd | Wholesale & retail | 2025 |
| Capital City Cleaning Company Ltd | Administrative & support | 2013 |
| Capital Consultants and Investments Ltd | Financial services | 2022 |
| Caplen Estates Ltd | Real estate | 2017 |
| Caproig Associates Limited | Professional & scientific | 2016 |
| Car Pro Ltd | Wholesale & retail | 2021 |
| Care Medical Limited | Health & social care | 2010 |
| Careers Consulting Ltd | Professional & scientific | 2023 |
| Caribou Capital Business Advisory Ltd | Professional & scientific | 2020 |
| Caribou Capital Ltd | Professional & scientific | 2018 |
| Caribou Ventures I Ltd | Administrative & support | 2019 |
| Caring Touch Solutions Ltd | Health & social care | 2023 |
| Carlo Felice Limited | Wholesale & retail | 2016 |
| Carma Property Solutions Ltd | Real estate | 2020 |
| Carpe Noctum Limited | Arts & recreation | 2006 |
| Carragh Mcaree Limited | Health & social care | 2002 |
| Carter Owers Studio Ltd | Professional & scientific | 2020 |
| Casarustichella UK Limited | Hospitality | 2004 |
| Cash, Currency and Payments Limited | Other services | 2017 |
| Cassidy Media Consultancy Limited | Professional & scientific | 2010 |
| Cassis Cleaning Ltd | Administrative & support | 2025 |
| Castro Garcia Consulting Ltd | Professional & scientific | 2021 |
| Catalyst Productions Limited | Information & communication | 2014 |
| Caton Bell Ltd | Information & communication | 2013 |
| Caulder Moore Limited | Professional & scientific | 1998 |
| CB Hansen Limited | Professional & scientific | 2017 |
| CE Financial Operations Ltd | Professional & scientific | 2026 |
| Cedar Development Company Limited | Real estate | 1964 |
| Celsius Sports Limited | Wholesale & retail | 2022 |
| Centrals Agency Ltd | Professional & scientific | 2025 |
| Centras Group Limited | Financial services | 2026 |
| Centre of Excellence for Living Language Ltd | Education | 2022 |
| CF Brokers Limited | Financial services | 2025 |
| Ch&P Holdings Ltd | Financial services | 2025 |
| Chalcot Ventures Limited | Professional & scientific | 2012 |
| Chandhokproperty Limited | Real estate | 2017 |
| Change Activators Limited | Professional & scientific | 2013 |
| Chantry Estates London LLP | | 2023 |
| Chantry Securities Holding Company Limited | Real estate | 2003 |
| Chantry Securities Limited | Construction | 1999 |
| Chapel Court Management Company Limited | Households | 1986 |
| Chapel View Church Road Management Company Limited | Households | 2021 |
| Chapman Consulting Business Development Ltd | Professional & scientific | 2000 |
| Chard (London) Limited | Extraterritorial | 2008 |
| Charles Crehan Ltd | Professional & scientific | 2006 |
| Charlie Bravo Consulting Limited | Professional & scientific | 2025 |