| Carbis Bay Holdings Limited | Financial services | 2020 |
| Carbis Bay Holiday Lets Limited | Real estate | 2020 |
| Carbis Bay Hotel Limited | Hospitality | 2011 |
| Carbis Bay Property Limited | Construction | 2023 |
| Carclew Barton Ltd | Agriculture & fishing | 2023 |
| Carclew Investments Limited | Real estate | 2003 |
| Carden Property Developers (Cornwall) Limited | Construction | 2016 |
| Careers 4U CIC | Education | 2015 |
| Caretm Limited | Public administration | 2018 |
| Carleys of Cornwall Limited | Manufacturing | 2000 |
| Carlyon DRY Ltd | Hospitality | 2026 |
| Carmython Court Limited | Households | 1985 |
| Carn Brea Auctions Ltd | Wholesale & retail | 2016 |
| Carn Crew Ltd | Education | 2025 |
| Carne Farm and Fishing LLP | | 2023 |
| Carnego Systems Limited | Information & communication | 2006 |
| Carnon Contracting Limited | Professional & scientific | 1906 |
| Carnsworth Limited | Real estate | 2016 |
| Carolyn Susan Cygan-Dawson Limited | Extraterritorial | 2025 |
| Carpenter Hotels Limited | Financial services | 2017 |
| Carrara Carpentry Ltd | Construction | 2018 |
| Carrick House Management Company Limited | Households | 2023 |
| Carrington Wood Solutions Limited | Administrative & support | 2024 |
| Carter Co Cornwall Ltd | Financial services | 2021 |
| Carter-Hutchings Limited | Real estate | 2003 |
| Carters Packaging (Cornwall) Ltd | Financial services | 2020 |
| Carters Packaging Limited | Wholesale & retail | 2003 |
| Carters Property Holding Limited | Real estate | 2020 |
| Carthian Management Co Limited | Households | 2003 |
| Casa Carpentry Ltd | Construction | 2024 |
| Casale Consulting Limited | Information & communication | 2024 |
| Caspercat Holdings Limited | Financial services | 2021 |
| Castle View Developments 2019 Ltd | Construction | 2019 |
| Castlematter Limited | Transport & logistics | 1998 |
| Castlezens Construction Limited | Construction | 2016 |
| Catchin' Cards Limited | Wholesale & retail | 2025 |
| Cathedral Homes Limited | Construction | 1987 |
| Cathedral Vehicle Services Ltd | Wholesale & retail | 2023 |
| Cathedral View Holdings Limited | Financial services | 2006 |
| Cathedral View Limited | Health & social care | 2003 |
| Catherine Smith Accountants Ltd | Professional & scientific | 2022 |
| Cayton Blue Ltd | Construction | 2011 |
| CB Building & Developments Limited | Construction | 2015 |
| CBT Cornwall Psychological Services Ltd. | Health & social care | 2015 |
| CCG Southwest Ltd | Manufacturing | 2025 |
| CCH Plant Limited | Administrative & support | 2024 |
| Ccmescano Limited | Health & social care | 2025 |
| CCR Business Finance Limited | Financial services | 2005 |
| CCR Business Investments Limited | Financial services | 2023 |
| Cdaj Ltd | Professional & scientific | 2024 |
| Celtic Link Limited | Wholesale & retail | 2019 |
| Celtic Plastics Company Limited | | 1987 |
| CEM Consultancy Limited | Professional & scientific | 2002 |
| Centaur Projects Ltd | Construction | 2001 |
| Central Bar and Restaurant Limited | Hospitality | 2017 |
| Centrum Chiropractic Limited | Health & social care | 2015 |
| Cfmoto Center Ltd | Wholesale & retail | 2024 |
| Cfmoto Centre Ltd | Wholesale & retail | 2024 |
| CGR Estate FIC Limited | Financial services | 2013 |
| Chaap Holdings Ltd | Financial services | 2026 |
| Chaap Management Ltd | Professional & scientific | 2026 |
| Chacewater Garden Centre Limited | Wholesale & retail | 2018 |
| Chacewater Self Storage Limited | Real estate | 2016 |
| Challenger Quay Falmouth Management Limited | Real estate | 1999 |
| Chalro Properties Ltd | Construction | 2024 |
| Champions Gym Ltd | Arts & recreation | 2022 |
| Channel Digital Limited | Information & communication | 2007 |
| Chaos Cornwall CIC | Health & social care | 2014 |
| Chaos Group Cornwall Ltd | Financial services | 2022 |
| Chapel Hill Consultancy (Truro) LLP | | 2020 |
| Chapel Meadows (Porthtowan) Limited | Extraterritorial | 2013 |
| Chapel REI Limited | Real estate | 2024 |
| Chapel Rock Limited | Information & communication | 1996 |
| Chapman Drilling Ltd | Mining & quarrying | 2019 |
| Charlestown Harbour Limited | Arts & recreation | 2006 |
| Charlie Blake Motors Ltd | Wholesale & retail | 2026 |
| Charlies Angels Cleaning Services Limited | Administrative & support | 2012 |
| Charlottes Way Apartments Limited | Households | 2017 |
| Charterwood Commercial Property Consultants Ltd | Administrative & support | 2003 |
| Chateau DU Doux Ltd | Construction | 1996 |
| Chbn Community Radio CIC | Information & communication | 2011 |
| Cheat Codezzz Ltd | Hospitality | 2025 |
| Checkmyfile Limited | Financial services | 2003 |
| Chenoweths Business Park Limited | Real estate | 2008 |
| Chenoweths Holdings Ltd | Wholesale & retail | 2018 |
| Chenoweths Industries Ltd | Construction | 2021 |
| Cher Varya Commercial Ltd | Real estate | 2014 |
| Cher Varya Construction Limited | Construction | 2013 |
| Cher Varya Development Limited | Administrative & support | 2009 |
| Cher Varya Group Limited | Real estate | 1995 |
| Cher Varya Housing Limited | Real estate | 1996 |
| Cherrytop Weddings Ltd | Arts & recreation | 2020 |
| Chester Court Management Company (Newquay) Limited | Real estate | 1988 |
| Chesterton Medical Ltd | Health & social care | 2025 |
| CHI an MOR Ltd. | Households | 2021 |
| CHI Hevra Limited | Real estate | 2025 |
| CHI Lowen Cornwall Limited | Health & social care | 2025 |
| CHI Lowen Drive Management Company Limited | Households | 2020 |
| China Development Consulting Limited | Manufacturing | 2019 |
| Chippy TOM Ltd | Construction | 2016 |