| Brampton Chase Management Limited | Real estate | 1989 |
| Brandon James Design Limited | Administrative & support | 2003 |
| Bray Pharma Limited | Wholesale & retail | 2018 |
| Bray Reach Wealth Management Limited | Financial services | 2013 |
| Breakthrough Labs Ltd | Professional & scientific | 2022 |
| Breathnach Financial Services Compliance Consulting Limited | Financial services | 2018 |
| Bremont Watch Company Limited | Manufacturing | 2005 |
| Brep Student Ltd | Financial services | 2017 |
| Brick Investing Ltd | Wholesale & retail | 2020 |
| Bridge Technology Ltd | Information & communication | 2021 |
| Bridgend Flannel Mill Development Limited | Real estate | 1999 |
| Brighter Lives Ltd | Administrative & support | 2010 |
| Brightstock Financial Planning Ltd | Financial services | 2023 |
| Brightwell Associates Services Limited | Administrative & support | 2007 |
| Brimpton Landings Ltd | Real estate | 2025 |
| Brix Trade Holdings Ltd. | Information & communication | 2024 |
| Brixx UK Limited | Information & communication | 2010 |
| Broadcast Service Centre Limited | Manufacturing | 1993 |
| Broadlands Retail Group Limited | Wholesale & retail | 2020 |
| Brompton Shipping Ltd | Wholesale & retail | 2017 |
| Brookes Private Credit Limited | Financial services | 2025 |
| Brooks Building & Development Ltd | Construction | 2023 |
| Brookstones Property Solutions Limited | Real estate | 2013 |
| Brown OWL Consulting Limited | Information & communication | 2024 |
| Brunswick Investment Management Limited | Financial services | 2013 |
| Bruton Charles Audit Services Ltd | Professional & scientific | 2026 |
| Bruton Charles Business Support Ltd | Information & communication | 2011 |
| Bruton Charles Systems Limited | Administrative & support | 1986 |
| Bucknall Property Investments Ltd | Construction | 2022 |
| Buffery Secretaries Ltd | Extraterritorial | 2024 |
| Bugaboo UK Limited | Wholesale & retail | 2011 |
| Bulstrode Camp Limited | Real estate | 1971 |
| Bunker Hill Ventures Ltd | Professional & scientific | 2025 |
| Burroughs Financial Limited | Professional & scientific | 2020 |
| Business Alchemy Limited | Information & communication | 2012 |
| Business Operations Solution Services Limited | Professional & scientific | 2019 |
| Busykind Limited | Information & communication | 2000 |
| Butlers Yard Management Company Limited | Households | 2002 |
| Butterfly Accounting Ltd | Professional & scientific | 2025 |
| Buy Solutions Ltd | Real estate | 2013 |
| C a Home Improvements Ltd | Construction | 2025 |
| C E C Management Company Limited | Households | 1998 |
| C Grow Limited | Administrative & support | 2014 |
| C M Investment Nominees Limited | Extraterritorial | 1988 |
| Cacao Sita Ltd | Wholesale & retail | 2025 |
| Cadogan Publishing Limited | Professional & scientific | 2021 |
| Cafe 1870 Ltd | Hospitality | 2022 |
| Cafecreate Trustee Limited | Administrative & support | 2019 |
| Calder Wolff Limited | Administrative & support | 2022 |
| Calibrate Creative Consultancy Ltd | Administrative & support | 2017 |
| Camp Road Estates Limited | Real estate | 1996 |
| Campbell Gray Hotels Limited | Professional & scientific | 2002 |
| Campion Project Consultants Limited | Professional & scientific | 2014 |
| Canterbury Systems Limited | Real estate | 1971 |
| Capital Investment Partners Limited | Administrative & support | 2007 |
| Capsafa Ltd | Information & communication | 2026 |
| Carbon Offsets Limited | Other services | 2006 |
| Care Bridge Specialists Limited | Administrative & support | 2020 |
| CARED4 Care Services Ltd | Public administration | 2024 |
| Carle Consulting Limited | Professional & scientific | 2011 |
| Carruthers Court Management Limited | Households | 2014 |
| Carter Consultants Limited | Professional & scientific | 2015 |
| Cartridge Zone Ltd | Wholesale & retail | 2012 |
| Casey Construction (London) Ltd | Construction | 2025 |
| Castelian Marsh Limited | Professional & scientific | 2015 |
| Castle Hill Shutters Limited | Wholesale & retail | 2012 |
| Castle Street Wallingford Management Company Limited | Households | 2009 |
| Catenaix Limited | Information & communication | 2022 |
| Cath Jones Consulting Limited | Professional & scientific | 2019 |
| Catherine Jones Marketing and Communications Limited | Professional & scientific | 2021 |
| Cawlporth.Property Ltd | Construction | 2026 |
| Caxton House Properties Limited | Construction | 2026 |
| CAZ Studio Limited | Manufacturing | 2023 |
| CB Food Solutions Limited | Professional & scientific | 2018 |
| CB Pool Servicing Limited | Construction | 2011 |
| CBB London Limited | Professional & scientific | 2019 |
| Cdtl International Limited | Professional & scientific | 2007 |
| CDV Architects Ltd | Professional & scientific | 2007 |
| Cedar Court Management (Henley) Limited | Households | 2009 |
| Celia Byatt Event Consultancy Limited | Administrative & support | 2011 |
| Central Brooke Ltd | Real estate | 2024 |
| Central Suites Capital Ltd | Real estate | 2020 |
| Central Suites Limited | Real estate | 2018 |
| Central Suites R1 Limited | Real estate | 2019 |
| Century Galleries Limited | Other services | 1970 |
| Cerniqa Ltd | Information & communication | 2025 |
| CFD Holdings Ltd | Real estate | 2024 |
| Cfma Limited | Professional & scientific | 2012 |
| Chair School LLP | | 2025 |
| Chalcraft Management Company Limited | Households | 1985 |
| Challis Financial Ltd | Other services | 2019 |
| Chalmore Partners Ltd | Professional & scientific | 2021 |
| Change Delivery Consulting Limited | Professional & scientific | 2011 |
| Changebright Property Management Limited | Households | 1988 |
| Chaps (Southern) Limited | Construction | 2007 |
| Charity Consultants Limited | Professional & scientific | 1990 |
| Charlotte Barton Property Ltd | Real estate | 2024 |
| Charter House Management Company (Wantage) Limited | Households | 1989 |
| Chartersfields Management Company Limited | Households | 1999 |
| Chatham Place (Building 1) Manco Limited | Households | 2004 |