| Chichester House Bexhill Limited | Households | 1997 |
| Chris Walker Music Ltd | Administrative & support | 2005 |
| Chris Wright Construction Limited | Construction | 2006 |
| Chris's Cleaning Company Limited | Administrative & support | 2003 |
| Christie Management Limited | Professional & scientific | 1972 |
| Chromatics UK Ltd | Manufacturing | 2006 |
| Church Communities UK | Information & communication | 1948 |
| Churchill & SIM International Ltd. | Agriculture & fishing | 1994 |
| Churchill & SIM Limited | Agriculture & fishing | 1997 |
| Cinque Port Arms Limited | Hospitality | 2007 |
| City Pointing Systems Limited | Wholesale & retail | 1989 |
| Cityscale Limited | Real estate | 2000 |
| CJL Airworthiness Compliance Ltd | Professional & scientific | 2022 |
| Claimwatch Limited | Information & communication | 2002 |
| Claire Haigh Associates Ltd | Professional & scientific | 2006 |
| Clariso Limited | Information & communication | 2007 |
| Clarity Alliance Ltd | Other services | 1989 |
| Clark's Valeting Limited | Administrative & support | 2004 |
| Clarke Roofing (Southern) Limited | Construction | 1994 |
| Classic FOX Records Limited | Information & communication | 1998 |
| Clatplan Limited | Households | 1988 |
| Clause One Consulting Limited | Administrative & support | 2016 |
| Cleancut (South East) Limited | Administrative & support | 2007 |
| Clear Thinking (Software) Limited | Information & communication | 1986 |
| Clear Thinking Limited | Extraterritorial | 1988 |
| Clethorne Properties Limited | Real estate | 2002 |
| Cleveland Fencing Ltd | Construction | 2026 |
| Clever Kids Limited | Education | 2007 |
| Climpson Brothers Tree Surgeons Limited | Administrative & support | 2006 |
| Clinton Construction Limited | Wholesale & retail | 1980 |
| Clive Richardson Tours Limited | Administrative & support | 2002 |
| CLM Planning Limited | Professional & scientific | 2006 |
| Cloche IT Solutions Limited | Information & communication | 2004 |
| Club 4 Kids Limited | Education | 2002 |
| Coast Chiropractic Limited | Health & social care | 2006 |
| Coastal Management Limited | Real estate | 1996 |
| Cochrane Design 5 Limited | Real estate | 2018 |
| Cockshut Road Residents Association Limited | Extraterritorial | 1973 |
| Coffee Table TV Limited | Administrative & support | 2003 |
| Colebrooke Consulting Limited | Arts & recreation | 1983 |
| Colin Swansborough Limited | Extraterritorial | 2001 |
| Collaborative Connections Limited | Information & communication | 1999 |
| College Road Management Company Limited | Households | 1999 |
| Collier Enterprises Limited | Real estate | 1980 |
| Collings Decor Limited | Construction | 2005 |
| Collington Close Company Limited | Real estate | 1986 |
| Collins Enterprises (UK) Limited | Financial services | 2006 |
| Collins Planning Services Limited | Construction | 2006 |
| Commercial Catering Contracts Limited | Administrative & support | 2004 |
| Commercial Printing and Stationery Company,Limited(The) | Professional & scientific | 1895 |
| Commercials Cost Control Limited | Professional & scientific | 1991 |
| Community Training Assistance and Support (Ctas) Limited | Health & social care | 2004 |
| Compagnie Privee D'Import & D'Export Ltd | Wholesale & retail | 1998 |
| Company 39 Limited | Professional & scientific | 1999 |
| Company Secretaries (South) Limited | Administrative & support | 2005 |
| Complete Electrical Service Limited | Construction | 2005 |
| Complete Housewares Limited | Wholesale & retail | 2003 |
| Comprehensive Business Consultants Limited | Professional & scientific | 1995 |
| Computer Assignments Limited | | 1985 |
| Computer Security Management Limited | Professional & scientific | 2002 |
| Comtec | | 1996 |
| Concordia (UK) | Administrative & support | 1943 |
| Conquest a I Limited | Wholesale & retail | 2003 |
| Constant Fire and Electrical Ltd | Public administration | 2005 |
| Contactright Limited | Information & communication | 1988 |
| Contain-Er Protection Solutions Limited | Wholesale & retail | 2005 |
| Cook Brighton Limited | Construction | 1930 |
| Coombe Developments Limited | Construction | 1974 |
| Coombe Hill Pharmacy Limited | Wholesale & retail | 2007 |
| Coomber Roofing Limited | Construction | 2003 |
| Cooper and Purdey Limited | Administrative & support | 2002 |
| Cooper Racing Ltd | Administrative & support | 2002 |
| Coppard Plant Hire Limited | Construction | 1972 |
| Coppercrest Investments Limited | Real estate | 1987 |
| Copylink Digital Limited | Wholesale & retail | 2002 |
| Cordless Limited | Construction | 2001 |
| Corehouse Limited | Construction | 1994 |
| Corin Dudley Electrical Services Limited | Construction | 2002 |
| Corner Market Ltd | Wholesale & retail | 2019 |
| Cornford Builders Limited | Construction | 2006 |
| Corporate Potential Ltd | Education | 2005 |
| Countrival Limited | Construction | 1987 |
| Country Carers Limited | Health & social care | 2003 |
| Court Garden Limited | Manufacturing | 1977 |
| Courtenay Towers Hove Limited | Households | 2003 |
| Courtfold Limited | Water & waste | 1981 |
| Covey Consulting Ltd | Professional & scientific | 2024 |
| Cowie Montgomery Architects LLP | | 2006 |
| COX & Taylor Limited | Construction | 1981 |
| COX Development Company (Eastbourne) Limited | Real estate | 2003 |
| CPS Language Services Limited | Professional & scientific | 2000 |
| Craigholme (Bexhill) Limited | Households | 1958 |
| Crawley Window Company Limited | | 1983 |
| Crazy Chameleon Limited | Information & communication | 1997 |
| Cream Decorators Limited | Construction | 2005 |
| Createcan Limited | Information & communication | 1997 |
| Creative Curators Limited | Wholesale & retail | 1997 |
| Crestex (U.K.) Limited | Arts & recreation | 1989 |
| CRF Surveyors Ltd | Professional & scientific | 2013 |
| Croft Glass Home Improvements Ltd. | Professional & scientific | 1998 |