| Cantideck | Manufacturing | 2006 |
| Canton & Co Holdings Ltd | Real estate | 2026 |
| Capella Print Ltd | Professional & scientific | 2025 |
| Capio Ltd | Information & communication | 2026 |
| Capital and Scull Limited | Professional & scientific | 2018 |
| Captivating India Limited | Wholesale & retail | 2025 |
| Carbon Technical Limited | Professional & scientific | 2010 |
| Carbon Zero Solutions Limited | Households | 2023 |
| Cardoso Property Management Ltd | Administrative & support | 2022 |
| Care Home Bedding and More Ltd | Wholesale & retail | 2023 |
| Care Home Interiors Group Ltd | Financial services | 2024 |
| Care Home Interiors Ltd | Administrative & support | 2014 |
| Care Home Photo Furnishings Ltd | Manufacturing | 2023 |
| Care Home Rental Furniture Ltd | Wholesale & retail | 2023 |
| Carly Ferguson Consulting Ltd | Other services | 2017 |
| Carol Willey Market Research Limited | Professional & scientific | 2014 |
| Carriera Limited | Administrative & support | 2011 |
| Cartbridge Marina Group Limited | Real estate | 2024 |
| Cartbridge Marina Limited | Real estate | 2024 |
| Carterman Property Investments Ltd | Real estate | 2019 |
| Casalee Ltd | Wholesale & retail | 2019 |
| Casas V M Ltd | Real estate | 2019 |
| Caserta Investments Limited | Construction | 1994 |
| Cassidy's Bar Ltd | Hospitality | 2022 |
| Cassini International Property Limited | Real estate | 2007 |
| Cast Group Limited | Wholesale & retail | 1999 |
| Castle Creek Music Ltd | Information & communication | 2024 |
| Caterpillars Montessori Limited | Education | 2006 |
| Cato Computers Ltd | Wholesale & retail | 2012 |
| Caution Runners Limited | Wholesale & retail | 1993 |
| Cavendish Place (Hydefarm) Limited | Professional & scientific | 2002 |
| Cbme Consulting Ltd | Administrative & support | 2026 |
| Cccs Holdings Ltd | Financial services | 2022 |
| Cedar Courtyard Ltd | Hospitality | 2016 |
| Celerity Space Ltd | Information & communication | 2026 |
| Cemetery Field S5 CH LLP | | 2014 |
| Centiel (Holdings) Ltd. | Financial services | 2016 |
| Centiel UK Limited | Information & communication | 2005 |
| Centra Support Services Holding Company Limited | Financial services | 2016 |
| Centralfinal Residents Management Limited | Households | 1988 |
| Ceress Foods Limited | Extraterritorial | 2025 |
| CFM Racing Limited | Wholesale & retail | 2023 |
| Chadney Bulgin LLP | | 2008 |
| Chalet Tintin Limited | Real estate | 2013 |
| Chamberlain Contracts Limited | Construction | 2015 |
| Champagne Limited | Other services | 2025 |
| Chapel Gardens Estate Limited | Real estate | 2026 |
| Character Construction (London) Ltd | Construction | 2019 |
| Charcot Limited | Real estate | 2017 |
| Chariya's Kitchen Limited | Hospitality | 2023 |
| Charles Henry EA Limited | Real estate | 2022 |
| Charles Read & Daughter Limited | Other services | 1989 |
| Charltons Management Company (Odiham) Limited | Extraterritorial | 2001 |
| Charnham Park Limited | Real estate | 1990 |
| Chavez Consulting Ltd | Professional & scientific | 2021 |
| Chawilbe Just Software Limited | Information & communication | 2023 |
| Chawton House Library | Arts & recreation | 1993 |
| Chawton Innovation Services Limited | Professional & scientific | 2009 |
| Chawton Park Indoor Bowls Club Limited | Arts & recreation | 1995 |
| Chawton Park Limited | Arts & recreation | 2021 |
| Check My Quotes Ltd | Information & communication | 2026 |
| Cheese Louise Ltd | Wholesale & retail | 2024 |
| Chefs Kitchen Alton Ltd | Hospitality | 2021 |
| Chelsea Colorectal Investments Ltd | Health & social care | 2017 |
| Chelsea Surgical Consulting Ltd | Health & social care | 2017 |
| Cheriton Garage Limited | Wholesale & retail | 2006 |
| Cherry's Fitness Suite Limited | Arts & recreation | 2015 |
| Chesham Estates (Holdings) Limited | Financial services | 2013 |
| Chesham Estates Limited | Real estate | 2008 |
| Chichester (T) Hairdressing Limited | Other services | 1995 |
| Chichester Trading Ltd | Wholesale & retail | 2017 |
| Chilcroft Homes Limited | Construction | 2019 |
| Chillpoint Ltd | Manufacturing | 2018 |
| China Garden Alton Limited | Hospitality | 2023 |
| Chiswick High Road 2 Limited | Other services | 2018 |
| Chris Abbotts Workshops Limited | Wholesale & retail | 2002 |
| Chris Coles Broadcasting Ltd | Information & communication | 2020 |
| Chris Dunford Limited | Information & communication | 2010 |
| Chris KAY Heating Limited | Construction | 2015 |
| Chris Moore Transport Company Limited | Construction | 1997 |
| Christopher Janes Recruitment Ltd | Administrative & support | 2018 |
| Christou Electrics Ltd | Construction | 2019 |
| Chronic Art Limited | Wholesale & retail | 2023 |
| Church Farm Hilfield Limited | Agriculture & fishing | 2021 |
| CHX Challenge Ltd | Administrative & support | 2021 |
| Cinechem Foto Limited | Professional & scientific | 2012 |
| Cinema Printing Company London Ltd | Manufacturing | 2014 |
| Cinetech UK Ltd | Manufacturing | 2011 |
| Cineverse Limited | Information & communication | 2024 |
| Cipher Films Limited | Information & communication | 2003 |
| Circai Ltd | Information & communication | 2025 |
| Cirsium Limited | Hospitality | 2020 |
| Cityscape Medical Ltd | Health & social care | 2022 |
| CJ and AJ Sanderson Ltd | Professional & scientific | 2014 |
| CK2MMM Trading AS Corporate Occupational Health Limited | Health & social care | 2016 |
| CKS Plumbing and Heating Engineers Limited | Construction | 2007 |
| CL Carpentry Ltd | Construction | 2026 |
| Claines Limited | Professional & scientific | 2018 |
| Clapham (T) Hairdressing Limited | Other services | 2003 |
| Clarendon Properties Limited | Construction | 1987 |