| Chelmsford St.Annes School Limited | Education | 1960 |
| Chelsea Creative Lighting Ltd | Wholesale & retail | 2016 |
| Cheltenham Trading Limited | Financial services | 1998 |
| Chemprindex Limited | Other services | 2018 |
| Chennells Investment Management Ltd | Financial services | 2007 |
| Chepworth Limited | Professional & scientific | 1981 |
| Cherry Tree IT Limited | Information & communication | 2004 |
| Chesterfield Food Limited | Hospitality | 2025 |
| Chesterton Properties Limited | Real estate | 1993 |
| Chestnut Court (Newport) Residents Association Limited | Households | 2002 |
| Chevick Consulting Limited | Health & social care | 2022 |
| Cheyvoc Ltd | Health & social care | 2022 |
| Chibili Homes Ltd | Real estate | 2025 |
| Chick - N - DIP Ltd | Hospitality | 2024 |
| Chick DIP Limited | Wholesale & retail | 2017 |
| Chicken HUT Limited | Hospitality | 1998 |
| Chiecare Ltd | Health & social care | 2018 |
| Chief Clicks Ltd | Professional & scientific | 2025 |
| Chigoz Medical Ltd | Health & social care | 2024 |
| Chigwell Grove Management Company Limited | Households | 2017 |
| Chigwell Investment Limited | Real estate | 2023 |
| Chigwell Mitre Enterprises Limited | Real estate | 1992 |
| Chigwell Spice Limited | Hospitality | 2018 |
| Chigwell Valet Limited | Other services | 2006 |
| Chilton Place (Sudbury) Residents Management Company Limited | Households | 2020 |
| Chin Chin Holdings Limited | Hospitality | 2023 |
| Chinwejov Ltd | Health & social care | 2012 |
| Chinwosu Limited | Professional & scientific | 2017 |
| Chiq-Cliq PVT Ltd | Wholesale & retail | 2024 |
| Chisholm & Winch (Building Services) Limited | Construction | 1983 |
| Chisholm & Winch (Contracts) Ltd | Construction | 1962 |
| Chisholm & Winch Limited | Administrative & support | 1973 |
| Chittinghurst Construction Limited | Construction | 2002 |
| Chivisa Healthcare Limited | Health & social care | 2023 |
| Chlor-Alkali SH (Ca-Sh) Limited | Other services | 2018 |
| Choice Discount Stores Limited | Wholesale & retail | 1983 |
| Choice Homes Limited | Wholesale & retail | 1964 |
| Choose to Build Ltd | Construction | 2024 |
| Choppers Barbers Ltd | Other services | 2024 |
| Chorley Timber (London) Limited | Wholesale & retail | 1989 |
| Chovin Ltd | Other services | 2022 |
| Chowdhury Biriyani & Catering (UK) Ltd | Hospitality | 2020 |
| Chowdhury Estates Ltd | Real estate | 2002 |
| Chowza Limited | Manufacturing | 2024 |
| Chris Diagnostic Hub Limited | Health & social care | 2026 |
| Chris Gosling Ceramics Ltd | Construction | 2007 |
| Chris Kyan Ltd | Wholesale & retail | 2001 |
| Chris Oddy Productions Limited | Information & communication | 2006 |
| Christ Apostolic Church Total Victory Christian Centre Ltd. | Other services | 2008 |
| Christchurch Service Station Limited | Wholesale & retail | 1999 |
| Christian Behnam Ltd | Professional & scientific | 2007 |
| Christian Drama Resource Centre | Arts & recreation | 1997 |
| Christies (U.K.) Limited | | 1984 |
| Christies Office Pro Cleaning Ltd | Administrative & support | 2018 |
| Christmas Cactus Ltd | Wholesale & retail | 2023 |
| Christmas Developments Limited | Wholesale & retail | 1981 |
| Christopher MC COY Limited | Construction | 1976 |
| Chronicles Consulting Limited | Professional & scientific | 2012 |
| Chrust Solutions Limited | Information & communication | 2024 |
| Chrysus Gold Ltd | Wholesale & retail | 2023 |
| Church Farm Energy Centre Limited | Energy | 2019 |
| Church's (Pork Butchers) Limited | Wholesale & retail | 1986 |
| Churchill Beckett Partners Ltd | Arts & recreation | 2019 |
| Churchill Property Management Co Limited | Households | 1992 |
| Churchill Scaffolding Limited | Construction | 1987 |
| Chy-Mex Medicare Limited | Health & social care | 2025 |
| Cigamon Limited | Information & communication | 1994 |
| Ciking Ltd | Health & social care | 2015 |
| Cildes Croft Management Company Limited | Households | 2017 |
| Cinnamon Chai London Ltd | Hospitality | 2024 |
| Circad Design Limited | Manufacturing | 2001 |
| Circle Specialist Limited | Wholesale & retail | 2025 |
| Circling the Square Limited | Arts & recreation | 2002 |
| Circuit Creative Agency Ltd | Information & communication | 2021 |
| Circulus Technologies Limited | Wholesale & retail | 2026 |
| Citi Kitchen Ltd | Hospitality | 2023 |
| City & Country Warley Limited | Construction | 2003 |
| City & Essex Limited | Administrative & support | 1981 |
| City Law Associates | | 2007 |
| City Management Corporation Limited | Professional & scientific | 1988 |
| City Nest Properties Ltd | Hospitality | 2021 |
| City Shredding Services Limited | Wholesale & retail | 1977 |
| City Street Properties Limited | Real estate | 2000 |
| City Tax Management Consultants Ltd. | Professional & scientific | 1972 |
| City Telecom Services Limited | Information & communication | 1994 |
| Cityscheme Limited | Information & communication | 1987 |
| CJO Medical Services Ltd | Administrative & support | 2021 |
| CJR Photography Limited | Professional & scientific | 2009 |
| CK Consultations Ltd | Professional & scientific | 2025 |
| CK Pharma Consult Ltd | Administrative & support | 2017 |
| CKK Civil Engineering Limited | Construction | 2018 |
| CKM Management Ltd | Real estate | 2017 |
| CKS Accountancy Limited | Professional & scientific | 2003 |
| Clacton Electronics Limited | Wholesale & retail | 2004 |
| Clacton Tool Hire Limited | Wholesale & retail | 2002 |
| Clacton-On-Sea Golf Club Limited | Other services | 2006 |
| Clactons Limited | | 1989 |
| Claim Help UK Ltd | Other services | 2022 |
| Clare Harding Limited | Arts & recreation | 2003 |
| Clarivel Ltd | Wholesale & retail | 2025 |