| Cmadf Limited | Professional & scientific | 2023 |
| CMH Engineering Services Ltd | Construction | 1998 |
| CMK Surfacing Ltd | Construction | 2019 |
| CML Fibre Contractors Ltd | Construction | 2024 |
| CMP Groundworks and Paving Ltd | Construction | 2026 |
| CMS Plumbing & Heating Limited | Construction | 2008 |
| CNC Property Limited | Real estate | 2014 |
| Cnomo Limited | Other services | 2016 |
| CNS Homes Limited | Real estate | 2017 |
| CNS Luxe Homes Limited | Real estate | 2025 |
| Coach Hire Connect Limited | Transport & logistics | 2025 |
| Coach Works Enterprises Limited | Real estate | 2024 |
| Coachai Ltd | Information & communication | 2025 |
| Coah Hair Limited | Other services | 2022 |
| Coalesce Construction Limited | Construction | 2017 |
| Coalesce Group Limited | Financial services | 2022 |
| Coast & Country Roofing & Construction Ltd | Construction | 2023 |
| Coast Communications Limited | Professional & scientific | 2003 |
| Coast Pro Limited | Construction | 2016 |
| Coastal Collective (Kent) Limited | Real estate | 2018 |
| Coastal Property Management Services Limited | Real estate | 2021 |
| Coates Carpentry & Building Limited | Construction | 2018 |
| Cobb Lettings Limited | Real estate | 2023 |
| Cobblers One Limited | Other services | 2022 |
| Cobblers Two Limited | Other services | 2022 |
| Cobham Court Landscaping Ltd | Administrative & support | 2010 |
| Cobham Electrical Contractors Ltd | Construction | 2026 |
| Coda Commerce Limited | Other services | 1999 |
| Coda Commerce Property Ltd | Other services | 2020 |
| Codac Consultancy Limited | Professional & scientific | 2019 |
| Code Blue Automation Limited | Construction | 2026 |
| Codeblitz Limited | Wholesale & retail | 2025 |
| Coffee Bean Holdings Limited | Manufacturing | 2019 |
| Coffee Bean Shop Company (Kent) Ltd | Real estate | 2020 |
| Coffee Bean Shop Limited | Manufacturing | 2008 |
| Coffee Doctors Ltd | Other services | 2018 |
| Coffee Operations Limited | Other services | 2020 |
| Cognet Limited | Real estate | 2021 |
| Cognitiv Ltd | Real estate | 2008 |
| Col-Cot Travel Ltd | Administrative & support | 2025 |
| Colbeck ROE Construction Limited | Construction | 2012 |
| Colby Capital Limited | Extraterritorial | 2010 |
| Cold Case Limited | Manufacturing | 2010 |
| Coldfix Solutions Limited | Construction | 2019 |
| Coldweld Limited | Extraterritorial | 2000 |
| Cole & Co Ashford Limited | Professional & scientific | 2025 |
| Colefax Place Management Company Limited | Households | 1999 |
| Colin Batt Removals Limited | Transport & logistics | 2012 |
| Colin Edwards Travel Limited | Information & communication | 1992 |
| Colin J Hall Ltd | Real estate | 2010 |
| Colin King Fire Consultancy Ltd | Public administration | 2025 |
| Colin Teevan Limited | Arts & recreation | 2010 |
| Colldale Airedale & Terriers Ltd | Agriculture & fishing | 2018 |
| Colleton Park (Hythe) Limited | Real estate | 2011 |
| Collins &T Wholesala Limited | Wholesale & retail | 2021 |
| Collins Bespoke Homes Limited | Construction | 2022 |
| Collins Bespoke Limited | Manufacturing | 2014 |
| Collins Medical Limited | Manufacturing | 2024 |
| Collum Securities Limited | Agriculture & fishing | 1973 |
| Colour ME Crazy (Shepperton) Ltd | Other services | 2021 |
| Colourful Homes Limited | Real estate | 2003 |
| Colt Stables (2016) Limited | Manufacturing | 2016 |
| Coltek (UK) Limited | Administrative & support | 2009 |
| Coltek Limited | Transport & logistics | 1992 |
| Column Limited | Construction | 2018 |
| Comcor (Bishop's Court) Ltd | Construction | 2023 |
| Comcor (Grand Parade) Ltd | Construction | 2023 |
| Comcor (Normandy) Ltd | Construction | 2023 |
| Comcor (Riviera) Ltd | Arts & recreation | 2024 |
| Comcor (Shepherds Wharf) Ltd | Construction | 2023 |
| Comcor (Tregenna) Ltd | Construction | 2023 |
| Comcor (Whitehill) Ltd | Construction | 2023 |
| Comcor (WRT) Ltd | Construction | 2023 |
| Comcor Capital Drake's Island Lending Limited | Financial services | 2023 |
| Comcor Capital Ltd | Financial services | 2023 |
| Comcor Construction Ltd | Construction | 2023 |
| Comcor Group Ltd | Financial services | 2023 |
| Comcor Investment Group Ltd | Administrative & support | 2024 |
| Comfy Abodes Limited | Real estate | 2019 |
| Commar Services Ltd | Administrative & support | 2006 |
| Commerce Solution Ltd | Wholesale & retail | 2022 |
| Commercial Chemical Brothers Limited | Administrative & support | 2020 |
| Commercial Financing Solutions Limited | Financial services | 2011 |
| Commercial Plumbing Services Ltd | Construction | 2024 |
| Comms Rocks Ltd | Professional & scientific | 2025 |
| COMMUNIC8ER Limited | Information & communication | 2024 |
| Community Impacts International C.I.C. | Information & communication | 2025 |
| Community Nursing & Care Agency Limited | Extraterritorial | 2016 |
| Companionship Services Ltd | Other services | 2024 |
| Company Team Ltd | Administrative & support | 2017 |
| Compasionate Care Ltd | Health & social care | 2025 |
| Compass Economic Development Group Limited | Professional & scientific | 2016 |
| Compass Economic Development International Limited | Professional & scientific | 2021 |
| Competition Cams Limited | Professional & scientific | 1987 |
| Competition Components Limited | Professional & scientific | 1987 |
| Competitive Edge Consultants Ltd | Professional & scientific | 2024 |
| Complete Cleaning Ltd | Administrative & support | 2023 |
| Complete Composite Systems Limited | Wholesale & retail | 2013 |
| Complete Hygenic Interiors & Canopies Ltd | Construction | 2023 |
| Complete Independent Inventories Limited | Other services | 2009 |