| Cacia Studio Ltd | Wholesale & retail | 2009 |
| Cadenza Rhapsody Limited | Professional & scientific | 2021 |
| Cafe Arora Ltd | Hospitality | 2023 |
| Cafe Astria Ltd | Hospitality | 2025 |
| Caffery Company Ltd | Health & social care | 2024 |
| Caffrey London Ltd | Professional & scientific | 2021 |
| Caitlin Roberts Design Ltd | Information & communication | 2025 |
| Cake Buzz Limited | Hospitality | 2020 |
| Calandra Ltd | Hospitality | 2026 |
| Calforma Ltd | Professional & scientific | 2025 |
| Cali Contractors Ltd | Construction | 2020 |
| Cali's House Ltd | Wholesale & retail | 2026 |
| Callaghan Interiors Ltd | Manufacturing | 1992 |
| Callaghan Kitchens Limited | Manufacturing | 2003 |
| Calma Barber Ltd | Other services | 2025 |
| Cambrian Consulting Limited | Professional & scientific | 2026 |
| Cambs Maison Ltd | Real estate | 2026 |
| Campbell Johnson Limited | Professional & scientific | 2022 |
| Canary Wharf Physiotherapy Limited | Health & social care | 2003 |
| Candiasoil Limited | Wholesale & retail | 2011 |
| Candor & Courage Ltd | Professional & scientific | 2020 |
| Candy and Mobile Assessories Ltd | Wholesale & retail | 2025 |
| CANINE2FIVE Ltd | Other services | 2019 |
| Canny Fish Limited | Professional & scientific | 2025 |
| CAP Ferret Films Ltd | Information & communication | 2024 |
| Capel Lodge Ltd | Households | 2024 |
| Caplis Ltd | Construction | 2015 |
| CAPTURVAT3 Ltd | Hospitality | 2025 |
| Capzul Ltd | Information & communication | 2015 |
| Caribbean Kitchen POT Ltd | Hospitality | 2024 |
| Carisbrooke House Limited | Households | 2015 |
| Carl Speck Ltd | Education | 2024 |
| Carling Court Residents Company Limited | Households | 1995 |
| Carmen Rendell Limited | Health & social care | 2024 |
| Caros Consulting Ltd | Administrative & support | 2016 |
| Carpet Town Retail Limited | Wholesale & retail | 1996 |
| Carpets Limited | Wholesale & retail | 2019 |
| Carphin Limited | Real estate | 2025 |
| Carr Humphreys Ltd | Professional & scientific | 2016 |
| Cartagena Ltd | Households | 2024 |
| Carvewise Ltd | Professional & scientific | 2022 |
| Casa Vita Management Limited | Real estate | 2025 |
| Casend Limited | Professional & scientific | 2007 |
| Casse Limited | Manufacturing | 2025 |
| Cast a Legacy Ltd | Wholesale & retail | 2025 |
| Castellan Services Ltd | Other services | 2026 |
| Castlemakers Ltd | Construction | 2020 |
| Castor Bay Property Limited | Real estate | 2017 |
| Cat Tarbuck Coaching & Consulting Ltd | Professional & scientific | 2023 |
| Catapult Business Solutions Ltd | Information & communication | 2008 |
| Catch Photos Ltd | Information & communication | 2024 |
| Caunton Farleigh Ltd | Professional & scientific | 2012 |
| Causer Buildings Management Limited | Administrative & support | 2014 |
| Cayley Wright & Associates Limited | Professional & scientific | 2022 |
| CB Legal Consulting Ltd | Professional & scientific | 2026 |
| CBB & Associates Ltd | Wholesale & retail | 2007 |
| Cbreaks Limited | Administrative & support | 2021 |
| Cctwickenham Ltd | Hospitality | 2026 |
| CD Broadcasting Ltd | Information & communication | 2024 |
| Cdaa Design Ltd | Professional & scientific | 2022 |
| Cecil Global Ltd | Other services | 2015 |
| Cedarlume Ltd | Financial services | 2026 |
| Cedarwood Homes Limited | Real estate | 2018 |
| Ceiba Tree Limited | Wholesale & retail | 2022 |
| Cellarmaster Wines (UK) Limited | Administrative & support | 1989 |
| Cellarmaster Wines Holdings (UK) Limited | Financial services | 1968 |
| Cellwether Ltd | Professional & scientific | 2010 |
| Cengiz Consultancy Ltd | Extraterritorial | 2016 |
| Central Maintenance Services (London) Limited | Construction | 2006 |
| Central Moves Group Limited | Financial services | 2024 |
| Central Moves Ltd | Transport & logistics | 2001 |
| Central Storage Ltd | Transport & logistics | 2014 |
| Centre for Access to Sport and Education (Case) C.I.C. | Education | 2025 |
| Centuary Construction Ltd | Construction | 2017 |
| CFX1M Ltd | Construction | 2025 |
| CGM S.E. Design Ltd | Professional & scientific | 2019 |
| Chaffey Properties Ltd | Real estate | 2022 |
| Chai Rendezvous Ltd | Hospitality | 2025 |
| Chainview Sports Ltd | Professional & scientific | 2025 |
| Chalfont Limited | Extraterritorial | 2017 |
| Chance Media Services Ltd | Information & communication | 2020 |
| Chandraveena Limited | Health & social care | 2022 |
| Change Education Consultancy Ltd | Education | 2020 |
| Chapellane Limited | Construction | 1996 |
| Chaps Barbering Epping Ltd | Other services | 2025 |
| Charge-Ez Ltd | Information & communication | 2024 |
| Chariot Heating Solutions Ltd | Construction | 2018 |
| Charles Alexander Property Holdings Limited | Real estate | 2017 |
| Charles Alexander Van DEN Berg Limited | Construction | 2017 |
| Charles DOE Architects Ltd | Professional & scientific | 2009 |
| Charlie Fowler Ltd | Professional & scientific | 2019 |
| Charlie Myers Consulting Limited | Administrative & support | 2012 |
| Charlotte Street Productions Ltd | Information & communication | 2013 |
| Chattaway Business Services Limited | Administrative & support | 1997 |
| Chattyconnell Ltd | Information & communication | 2024 |
| Chawner-Ellis Group Ltd | Wholesale & retail | 2025 |
| Chebi Ltd | Real estate | 2026 |
| Chebydesign Ltd | Construction | 2021 |
| Cheeky Chops Play Ltd | Arts & recreation | 2020 |
| Chekid OUT Limited | Information & communication | 2023 |