| Cascade Cars Limited | Wholesale & retail | 2003 |
| Castle Builders (South East) Limited | Construction | 2013 |
| Castlethorpe Homes Ltd | Construction | 2020 |
| Catering Exclusive Ltd | Hospitality | 2020 |
| Catherine Muller Flower School London Limited | Education | 2012 |
| Catherine Muller London Limited | Professional & scientific | 2012 |
| Catinas Trans Ltd | Transport & logistics | 2014 |
| Causeway Steel Products Limited | Manufacturing | 2002 |
| CB Accounting Solutions Ltd | Professional & scientific | 2010 |
| CB Carpets and Flooring Limited | Construction | 2018 |
| CB Childcare Limited | Health & social care | 2026 |
| CBN Accounting Ltd | Professional & scientific | 2020 |
| CBW Developments Limited | Construction | 2013 |
| Ccdde London Ltd | Financial services | 2020 |
| CCM Vettes Ltd | Wholesale & retail | 2017 |
| CCS Interiors Kent Ltd | Construction | 2024 |
| CD Electrical & Data Limited | Construction | 2023 |
| Cdis Group Limited | Information & communication | 2009 |
| Cdrm Services Limited | Construction | 2017 |
| Cedaroak Group of Companies Limited | Administrative & support | 2017 |
| Cedaroak Security Ltd | Administrative & support | 2016 |
| Cedaroak Security Services Ltd | Administrative & support | 2018 |
| Cedaroak Services (Central) Limited | Administrative & support | 2018 |
| Cedaroak Services Southern Limited | Administrative & support | 2014 |
| CEE Growth Limited | Professional & scientific | 2025 |
| CEG Site Surveys Limited | Construction | 2011 |
| CEI Formwork Ltd | Construction | 2023 |
| Celebrations and Decor Ltd | Hospitality | 2026 |
| Celestia Collectables Limited | Wholesale & retail | 2024 |
| Celiku Construction Ltd | Administrative & support | 2017 |
| Celtic Research Limited | Professional & scientific | 2002 |
| Cement Fields | Education | 2007 |
| Centa-Co Ltd | Health & social care | 2009 |
| Centaurus Property Management Limited | Real estate | 2021 |
| Central Leisure Developments Limited | Construction | 2012 |
| CENTRED4CARE Ltd | Health & social care | 2022 |
| Centreline Ltd | Administrative & support | 2025 |
| Centron Diagnostics Limited | Manufacturing | 2010 |
| Centrum Works Ltd | Administrative & support | 2015 |
| Centura Properties Limited | Real estate | 2000 |
| Cerface Construction Products Limited | Construction | 1968 |
| Certified Testers Ltd | Information & communication | 2023 |
| Certisa International Ltd | Information & communication | 2011 |
| Certisa Limited | Information & communication | 2004 |
| Certo Construction Ltd | Construction | 2017 |
| Cerulean Management Consultancy Limited | Professional & scientific | 2013 |
| CEW Investments Ltd | Real estate | 2024 |
| Ceylu Production Ltd | Information & communication | 2024 |
| CG Metalwork Ltd | Construction | 2020 |
| CG Talent Ltd | Information & communication | 2024 |
| CGC Consultancy Limited | Professional & scientific | 2019 |
| Cgen Property Ltd | Real estate | 2021 |
| Cgp&H Limited | Construction | 2016 |
| CH Accountancy Services Limited | Professional & scientific | 1993 |
| CH Designs Studio Ltd | Professional & scientific | 2020 |
| Chaccs Limited | Transport & logistics | 2016 |
| Chalfont Solutions Limited | Construction | 2015 |
| Chalk Marine Environmental Limited | Other services | 2022 |
| Chambers Interior Solutions Ltd | Construction | 2021 |
| Champion M.B.E. Limited | Real estate | 1983 |
| Chapman Builders Ltd | Construction | 2025 |
| Chapmans Refrigeration Limited | Energy | 2008 |
| Charis Real Estates Ltd | Real estate | 2017 |
| Charismacrowns Events Ltd | Hospitality | 2024 |
| Charles & SON Property Group Ltd | Real estate | 2024 |
| Charles Akle Limited | Administrative & support | 2005 |
| Charles Hotel Ltd | Hospitality | 2017 |
| Charlie One MP Limited | Administrative & support | 2015 |
| Charlotte Hill Ltd | Health & social care | 2019 |
| Charlton Contractors Ltd | Construction | 2008 |
| Charrette Holdings Ltd | Real estate | 2019 |
| Charrette Law Limited | Professional & scientific | 2024 |
| Chatam Noodle Bar Limited | Hospitality | 2020 |
| Chatha Hygiene Group Limited | Water & waste | 2018 |
| Chatha Hygiene Limited | Other services | 2007 |
| Chatham and District Model Railway Club C.I.C. | Other services | 2023 |
| Chatham Cambridge House Limited | Households | 2022 |
| Chatham Cash & Carry Ltd | Wholesale & retail | 2023 |
| Chatham Freight Station Ltd | Transport & logistics | 2001 |
| Chatham Historic Dockyard (Trading) Limited | Wholesale & retail | 1986 |
| Chatham Historic Dockyard Trust(The) | Arts & recreation | 1984 |
| Chatham Home Store Ltd | Wholesale & retail | 2025 |
| Chatham Maritime Car Park Management Limited | Administrative & support | 2013 |
| Chatham Maritime K1 Construction Limited | Construction | 1996 |
| Chatham Maritime K1 Developments Limited | Construction | 1996 |
| Chatham Maritime Management Ltd | Households | 2025 |
| Chatham Maritime Trust | Real estate | 1994 |
| Chatham MB Ltd | Wholesale & retail | 2021 |
| Chatham Mobile Accessories Ltd | Wholesale & retail | 2016 |
| Chatham Phones Ltd | Wholesale & retail | 2024 |
| Chatham Town Football Club (2000) Limited | Arts & recreation | 1999 |
| Chatham Town Women Football Club Ltd | Arts & recreation | 2020 |
| Chattels Solutions Limited | Professional & scientific | 2014 |
| Chattenden Syndicate Limited | Administrative & support | 2003 |
| Chava Building Ltd | Real estate | 2021 |
| CHD Procurement Services Limited | Wholesale & retail | 2020 |
| Cheeky Events Ltd | Hospitality | 2024 |
| Cheema Construction Services Limited | Construction | 2009 |
| Cheema Formwork Limited | Construction | 2008 |
| Cheema Site Services Limited | Construction | 2008 |