| C&C Consulting Limited | Administrative & support | 2024 |
| C&C Group Holdings Limited | Information & communication | 2004 |
| C-Tilde Ltd | Information & communication | 2024 |
| C. L. Properties Limited | Construction | 1929 |
| C.O.F. Developments Limited | Administrative & support | 1988 |
| C4 Plus Drainage Ltd | Water & waste | 2019 |
| C4D Ltd | Wholesale & retail | 2011 |
| Cabeck Holdings Limited | Real estate | 1964 |
| Caberfeigh Limited | Construction | 2009 |
| Caberfeigh Management Company Limited | Households | 2004 |
| Cache NET IT Limited | Information & communication | 2014 |
| Caddis Building Consultancy Limited | Real estate | 2010 |
| Cadogan Place (Horsham) Limited | Households | 2011 |
| Cadspire Design & Build Limited | Professional & scientific | 2017 |
| Caej Limited | Administrative & support | 1991 |
| Caenwood Estates Ltd | Real estate | 2021 |
| Cahootz Ltd | Professional & scientific | 2015 |
| Califig Ltd | Manufacturing | 2024 |
| Calum Kelly Designs Ltd | Manufacturing | 2024 |
| Calvers (Redhill) Limited | Administrative & support | 2003 |
| Calypso Bene Limited | Arts & recreation | 2023 |
| Calyxio Ltd | Information & communication | 2026 |
| Camcard Construction Ltd | Construction | 2021 |
| Camelot Court Ifield Ltd. | Households | 2008 |
| Cameron Specialty Europe Limited | Other services | 2024 |
| Camp Glide Ltd | Health & social care | 2013 |
| Campbell Close Management Co. Ltd | Households | 2016 |
| Camtech Data Solutions Ltd | Information & communication | 2018 |
| Canadian Spa Company Ltd | Wholesale & retail | 1999 |
| Candal Accountancy Limited | Professional & scientific | 2017 |
| Canons Training Solutions Limited | Administrative & support | 2008 |
| Canopy Partners Limited | Professional & scientific | 2026 |
| Cantico Consulting Limited | Professional & scientific | 2025 |
| Cantico Properties Limited | Real estate | 2022 |
| Capelton Property Holdings Ltd | Real estate | 2026 |
| Capital Maintenance Solutions Ltd | Construction | 2023 |
| Capital Water (London) Ltd | Water & waste | 2012 |
| Capital Water Treatment Compliance Limited | Water & waste | 2023 |
| Capital Water Treatment Limited | Water & waste | 1993 |
| Caravan Parks Limited | Hospitality | 1952 |
| Cardiff Student Living Ltd | Real estate | 2015 |
| Cardo Contractors Ltd (Global) Ltd | Construction | 2023 |
| Care Brick Damp Control UK Limited | Construction | 2014 |
| Care Calibre Limited | Health & social care | 2013 |
| Carecx Limited | Health & social care | 2025 |
| Carisbourne Limited | Households | 1977 |
| Carly Furnell Ltd | Administrative & support | 2024 |
| Carman Historic Ltd. | Wholesale & retail | 2016 |
| Carna Court Management Company Limited | Real estate | 2024 |
| Carpe Diem Network Limited | Other services | 2019 |
| Carpet Cave Limited | Wholesale & retail | 2007 |
| Carriage Walk Residents Limited | Households | 2011 |
| Cars Executive Ltd | Transport & logistics | 2024 |
| Carter Andrews Framing Ltd | Wholesale & retail | 2020 |
| Carter Brickwork Ltd | Construction | 2022 |
| Cartwright Creative Ltd | Professional & scientific | 2023 |
| Cartwright Pictures Ltd | Arts & recreation | 2023 |
| Casita Management Ltd | Real estate | 2024 |
| Castle Place Bletchingley Freehold Ltd | Households | 2013 |
| Castle Place Bletchingley Management Limited | Households | 2025 |
| Catalyst Architecture & Strategy Limited | Information & communication | 2025 |
| Catercall Ltd | Manufacturing | 2011 |
| Cathedral Consultancy Services Limited | Professional & scientific | 2018 |
| Catherine Lockett Fostering Services Ltd | Professional & scientific | 2019 |
| Cavendish House Estates LLP | | 2011 |
| Cayemel Limited | Professional & scientific | 2017 |
| CB Coaching Ltd | Education | 2021 |
| Cbsbutler Holdings Limited | Administrative & support | 2023 |
| CC and SJ Parker Limited | Health & social care | 2019 |
| Ccrl Consultancy Ltd | Professional & scientific | 2025 |
| CEC Engineering Services Limited | Construction | 1990 |
| Cedardrive Limited | Real estate | 1975 |
| Ceilp Wellness Limited | Wholesale & retail | 2025 |
| Celerity Care UK Limited | Administrative & support | 2022 |
| Celestial Audio Limited | Wholesale & retail | 2022 |
| Centauri Investments Ltd | Professional & scientific | 2025 |
| Centien Ltd | Professional & scientific | 2020 |
| Central News Limited | Information & communication | 1998 |
| Centre Court Management Limited | Real estate | 1985 |
| Ceramic Fitch Limited | Manufacturing | 2019 |
| CFM Financial Planning Ltd | Financial services | 2014 |
| CGW Investments Limited | Real estate | 2013 |
| Chailens Media and Marketing Ltd | Information & communication | 2024 |
| Chaiyo Lotus Thai Massage Ltd | Other services | 2026 |
| Chambers Accounting Services Limited | Professional & scientific | 2007 |
| Chance Cars Ltd | Transport & logistics | 2023 |
| Changing Minds Training Ltd | Education | 2021 |
| Chaoss Entertainment Ltd | Arts & recreation | 2023 |
| Chapel HAY Consulting Ltd | Information & communication | 2018 |
| Charles Maunders Consulting Ltd | Real estate | 2009 |
| Charlie Brown Dog Walking Ltd | Health & social care | 2018 |
| Charlwood Automotive Ltd | Wholesale & retail | 2012 |
| Chas Care Group Limited | Administrative & support | 2009 |
| Chas Developments Limited | Administrative & support | 2011 |
| Chas Investments Limited | Real estate | 2026 |
| Chase Developments (Surrey) Ltd | Construction | 2019 |
| Chatton 2025 Ltd | Construction | 2025 |
| Chatwin Construction Limited | Construction | 1986 |
| Chatwin Property Lettings Limited | Real estate | 2004 |
| Cheeld Wheeler Limited | Financial services | 2002 |