| Carbisdale Ourhq Ltd | Real estate | 2018 |
| Carewenna Community Support Ltd | Health & social care | 2026 |
| Carlyon Bay Beach Shop Ltd | Wholesale & retail | 2022 |
| Carlyon Court Management Company Limited | Real estate | 2006 |
| Carnel Homes Limited | Real estate | 2002 |
| Caroline Couch Limited | Professional & scientific | 2007 |
| Carpalla Limited | Hospitality | 2014 |
| Casa MIA Management Company Limited | Hospitality | 2007 |
| Cataclew Ltd | Real estate | 2021 |
| Cate's Kottages Ltd | Hospitality | 2025 |
| CCM Construction SW Ltd | Construction | 2022 |
| Cedarcroft Nurseries Limited | Wholesale & retail | 2022 |
| Celtic Enterprises Limited | Real estate | 1958 |
| Cemas Deliveries Ltd | Transport & logistics | 2026 |
| Ceremo Ltd | Other services | 2025 |
| CG Transport & Recovery Ltd | Transport & logistics | 2024 |
| Chang LI Farm Ltd | Agriculture & fishing | 2014 |
| Chang LI Limited | Arts & recreation | 2005 |
| Chapman PCN Ltd | Construction | 2026 |
| Chapman's of Sevenoaks Limited | Wholesale & retail | 1997 |
| Chapmans Fish Brokers Limited | Wholesale & retail | 2006 |
| Charis Incorporated Limited | Hospitality | 2022 |
| Charles French Holdings Limited | Financial services | 2022 |
| Charles French Properties Limited | Real estate | 2022 |
| Charles French Solicitors Ltd | Professional & scientific | 2012 |
| Charlestown Harbour Gifts Ltd | Wholesale & retail | 2026 |
| Charlestown Joinery Ltd | Manufacturing | 2013 |
| Charlotte Brach Creative Ltd | Information & communication | 2025 |
| Chestnut Interiors and Lifestyle Limited | Professional & scientific | 2022 |
| Chetwood Investment Management Limited | Financial services | 2019 |
| Chetwood Private Wealth Limited | Financial services | 2018 |
| Chetwood Review Service Limited | Financial services | 2024 |
| Chetwood Wealth Management Ltd | Financial services | 2000 |
| CHG Adapt Limited | Construction | 2024 |
| Chief Electrical Limited | Construction | 2011 |
| CHY Blew Hair Limited | Other services | 2016 |
| CHY Kernow Holdings Limited | Financial services | 2025 |
| CIG Construction Ltd | Construction | 2022 |
| Circusinkuk Ltd | Other services | 2025 |
| CIS Group Holdings Ltd | Financial services | 2020 |
| Clay Country Commercial Services Limited | Professional & scientific | 2017 |
| Clay Country Dairy Ltd | Wholesale & retail | 2026 |
| CLEAN4YOU Ltd | Administrative & support | 2025 |
| Cleancare TJ Ltd | Administrative & support | 2025 |
| Cleavers Way Management Company Limited | Households | 2005 |
| Clieve Holdings Limited | Mining & quarrying | 2016 |
| Cloud Base Accounts Ltd | Professional & scientific | 2014 |
| Clougha Ltd | Information & communication | 2022 |
| Cluck N Games Ltd | Arts & recreation | 2026 |
| Cmd+Space Ltd | Information & communication | 2020 |
| Coast & Country Fires Limited | Construction | 2021 |
| Coast 2 Coast Security Ltd | Administrative & support | 2004 |
| Coast 2 Coast Security Storage & Training Ltd | Education | 2012 |
| Coastal I.T. Limited | Information & communication | 2000 |
| Coastal Specialist Ironmongery Limited | Wholesale & retail | 2008 |
| Coastal Woodburners Ltd | Wholesale & retail | 2023 |
| Colledge Optical Ltd | Professional & scientific | 2024 |
| College Oriental Limited | Extraterritorial | 2014 |
| Collings Brothers Developments Limited | Construction | 2023 |
| Colvin Builders Ltd | Construction | 2013 |
| Combellack Vehicle Recyclers Holdings Limited | Financial services | 2019 |
| Combellack Vehicle Recyclers Limited | Wholesale & retail | 1999 |
| Common Vegetation Management Limited | Agriculture & fishing | 2019 |
| Community 1ST Cornwall Limited | Real estate | 2004 |
| Community Cancer Cafes CIC | Other services | 2024 |
| Compass Bike Training Ltd | Education | 2019 |
| Connected Transport Limited | Transport & logistics | 2025 |
| Consultancy 3639 Ltd | Professional & scientific | 2025 |
| Contec South West Limited | Wholesale & retail | 2014 |
| Copper Bridge Limited | Hospitality | 2023 |
| Coral and Moss Limited | Construction | 2020 |
| Cornish Chowder Company Ltd | Manufacturing | 2024 |
| Cornish Flooring Limited | Construction | 2021 |
| Cornish Industrial Supplies Ltd | Wholesale & retail | 2014 |
| Cornish Inventories Ltd | Real estate | 2019 |
| Cornish K9 Ltd | Manufacturing | 2025 |
| Cornish Property Investments Ltd | Construction | 2016 |
| Cornish Seaside Cleaning LLP | | 2021 |
| Cornish Supplying Co Ltd | Wholesale & retail | 2021 |
| Cornish Sustainable Seafood Ltd | Agriculture & fishing | 2023 |
| Cornish Tails Ltd | Wholesale & retail | 2024 |
| Cornubia Marine LLP | | 2012 |
| Cornwall Adventure Limited | Education | 2007 |
| Cornwall Ambulance Service Limited | Health & social care | 2019 |
| Cornwall Association of Primary Headteachers Co-Operative CIC | Education | 2014 |
| Cornwall Blinds Ltd | Manufacturing | 2024 |
| Cornwall Building Solutions Limited | Manufacturing | 2023 |
| Cornwall Clear Limited | Health & social care | 2025 |
| Cornwall Clothing Company Ltd | Wholesale & retail | 2022 |
| Cornwall Co-Working Ltd | Administrative & support | 2026 |
| Cornwall Construction Limited | Construction | 2024 |
| Cornwall Crafts and Curios Ltd | Administrative & support | 2021 |
| Cornwall Defence Solicitors LLP | | 2009 |
| Cornwall Educational Psychology Ltd | Education | 2012 |
| Cornwall Executive Homes Ltd | Construction | 2018 |
| Cornwall Hair and Beauty Academy Ltd | Other services | 2020 |
| Cornwall Handyman Services Ltd | Construction | 2026 |
| Cornwall HCW Ltd | Other services | 2015 |
| Cornwall Hospice Care Lottery Limited | Arts & recreation | 2006 |
| Cornwall Hospice Care Trading Limited | Wholesale & retail | 2006 |