| Cmhb Consultancy Limited | Professional & scientific | 2020 |
| CNS Couriers Ltd | Transport & logistics | 2021 |
| Co-Lend Holdings Ltd | Financial services | 2019 |
| Co-Lend Ltd | Financial services | 2019 |
| Coach House HR Limited | Administrative & support | 2015 |
| Coalition Works Ltd | Professional & scientific | 2026 |
| Coast and County Properties Limited | Real estate | 1959 |
| Coastal Breeze Developments Limited | Construction | 2025 |
| Coastal Cardiology Limited | Health & social care | 2015 |
| Coates Brothers Limited | Information & communication | 2016 |
| Cobb & Jones Recruitment Ltd | Administrative & support | 2018 |
| Cobblestone Properties Limited | Real estate | 2003 |
| Cobnut Close Management Company Limited | Households | 2023 |
| Cobtree Landscapes Ltd | Administrative & support | 2018 |
| Cobwebb Communications Limited | Information & communication | 1986 |
| Codebook Consulting Limited | Professional & scientific | 2020 |
| Coldchain Ltd | Professional & scientific | 2023 |
| Coldrum Consulting Limited | Information & communication | 2012 |
| Coldthorn Limited | Construction | 2024 |
| Coleman Anderson Architects Limited | Professional & scientific | 1989 |
| Coleman Anderson Interiors Limited | Professional & scientific | 2024 |
| Coleman Webb Limited | Professional & scientific | 2007 |
| Colin Nightingale Ltd | Professional & scientific | 2017 |
| Collicutt Holdings Limited | Financial services | 2019 |
| Colmer Consulting Limited | Hospitality | 2017 |
| Colour by Rogers Limited | Information & communication | 2017 |
| Colrock Group Ltd | Financial services | 2025 |
| Colt-Classics Limited | Arts & recreation | 2012 |
| Colts Hill Investments Limited | Extraterritorial | 2020 |
| Columba Systems Holdings Limited | Extraterritorial | 2014 |
| Columba Systems Limited | Information & communication | 2002 |
| Combined Book Services Limited | Information & communication | 1988 |
| Comek Holdings Limited | Administrative & support | 2001 |
| Comet Associates Limited | Information & communication | 2018 |
| Comfort Zone Limited | Administrative & support | 1998 |
| Comit Legal Limited | Professional & scientific | 2014 |
| Commercial Door Specialists Ltd | Construction | 2021 |
| Commercial Pressure Cleaning Services Limited | Administrative & support | 2011 |
| Commsol Associates Limited | Professional & scientific | 2017 |
| Communicate Great Limited | Health & social care | 2017 |
| Company and Property Services Limited | Information & communication | 1983 |
| Compare Zone Ltd | Financial services | 2026 |
| Compass Business Finance Limited | Financial services | 2005 |
| Compass Business Investments 1 Limited | Financial services | 2021 |
| Compass Business Investments 2 Limited | Financial services | 2021 |
| Compass Business Investments Limited | Financial services | 2020 |
| Compass Investments Limited | Real estate | 2008 |
| Compass Miniature Railways Ltd | Wholesale & retail | 2003 |
| Complement Business Services Limited | Professional & scientific | 2014 |
| Complete Catering Consultancy Limited | Hospitality | 2024 |
| Concept AV Controls Ltd | Professional & scientific | 2018 |
| Concept Beauty Clinic Limited | Other services | 2023 |
| Concusse Ltd | Health & social care | 2021 |
| Conflict Check Ltd | Information & communication | 2017 |
| Congenital & Children's Heart Centre Ltd | Health & social care | 2010 |
| Consilium Developments Surrey Limited | Construction | 2015 |
| Constanti & Co Consulting Limited | Professional & scientific | 2015 |
| Construct IT London Ltd | Construction | 2023 |
| Consult SUE Reynolds Ltd | Professional & scientific | 2021 |
| Contacta Group Holdings Limited | Financial services | 2009 |
| Contacta Systems Limited | Manufacturing | 1994 |
| Container Homes and Conversions Ltd | Manufacturing | 2026 |
| Content Kweens Ltd | Professional & scientific | 2022 |
| Contrail Aviation Ltd | Education | 2023 |
| Control Tech Limited | Wholesale & retail | 1990 |
| Convenient Capital Limited | Financial services | 2022 |
| Conversation Positive Limited | Wholesale & retail | 2024 |
| Cook & Co Accountants LLP | | 2022 |
| Cool Company Media Limited | Other services | 2024 |
| Cool Plumbings Ltd | Construction | 2023 |
| Coombe Court (Beckenham) Freehold Limited | Households | 2006 |
| Coombe Court (Beckenham) Management Limited | Households | 1977 |
| Cooper Fine Art & Antiques Limited | Wholesale & retail | 2025 |
| Copper Moon Enbay Limited | Professional & scientific | 2026 |
| Copper Moon Seafood Limited | Professional & scientific | 2024 |
| Copyright Agent UK Ltd | Administrative & support | 2019 |
| Cora Interiors Limited | Professional & scientific | 2022 |
| Cora Works Ltd | Information & communication | 2026 |
| Coral Events Ltd | Administrative & support | 2025 |
| Core Commercial Limited | Real estate | 1996 |
| Corma Ltd | Construction | 2014 |
| Cornerstone Christian Fellowship | Other services | 2011 |
| Cornish Forestry Products Limited | Agriculture & fishing | 2020 |
| Corredor Mcdonnell Medics Limited | Health & social care | 2019 |
| Corvus Properties Ltd | Real estate | 2025 |
| Cosmetic Car Care Company Ltd | Wholesale & retail | 2006 |
| Cosmos Innovation Ltd | Information & communication | 2011 |
| Cosmos Risk Solutions Limited | Professional & scientific | 2001 |
| Costcon Limited | Construction | 2019 |
| Cottage Farms (Horsmonden) Limited | Agriculture & fishing | 1962 |
| Couchman Consultancy Services Limited | Professional & scientific | 2011 |
| Counting Backwards Ltd | Health & social care | 2025 |
| Country and Equestrian Properties Limited | Real estate | 2000 |
| Countryside Holidays Limited | Administrative & support | 2016 |
| County Dairies (Kent) Ltd | Wholesale & retail | 2024 |
| Couravel Limited | Professional & scientific | 2001 |
| Court Plumbing & Heating Contractors Ltd. | Construction | 2005 |
| Court Plumbing & Heating Installations Limited | Construction | 1976 |
| Courtley Planning Consultants Limited | Professional & scientific | 2015 |
| Courtney Havers LLP | | 2006 |