| Coast Path Couriers Ltd | Transport & logistics | 2023 |
| Coast to Coast Electrical Ltd | Construction | 2016 |
| Coastal Bliss Spa Limited | Other services | 2024 |
| Coastal Property Cornwall Ltd | Real estate | 2020 |
| Cober Valley Construction Limited | Construction | 2024 |
| Coffee Cargo Limited | Wholesale & retail | 2018 |
| Colbert Consultancy Services Limited | Other services | 1995 |
| Colin Midson Limited | Administrative & support | 2012 |
| Collington and Co Limited | Manufacturing | 2004 |
| Colmore Health Limited | Health & social care | 2016 |
| Combellack Accountancy Ltd | Professional & scientific | 2012 |
| Combined Leisure Limited | Administrative & support | 1992 |
| Compassionate Communities UK Ltd | Health & social care | 2026 |
| Condy Construction Ltd | Construction | 2025 |
| Constantine Quay Community Interest Company | Transport & logistics | 2020 |
| Constrapt Construction Ltd. | Construction | 2018 |
| Construct Global Limited | Real estate | 2021 |
| Content Homes Limited | Construction | 2014 |
| Cooke Pubs Ltd | Hospitality | 2015 |
| Cool Canvas Tent Company Limited | Wholesale & retail | 2015 |
| Coops & Co Limited | Construction | 2025 |
| Cornish Art Ltd | Wholesale & retail | 2022 |
| Cornish Cask Limited | Hospitality | 2024 |
| Cornish Cleans Ltd | Administrative & support | 2023 |
| Cornish Commercial Limited | Real estate | 2024 |
| Cornish Fish and Chips Limited | Financial services | 2020 |
| Cornish Freebird Limited | Hospitality | 2004 |
| Cornish Holiday Escapes Limited | Hospitality | 2011 |
| Cornish House Energy Ltd | Construction | 2023 |
| Cornish Retreats Ltd | Real estate | 2018 |
| Cornish Sea Salt Company Limited | Mining & quarrying | 2004 |
| Cornwall Against Dean Super Quarry Ltd | Other services | 2015 |
| Cornwall Appliance Holdings Ltd | Professional & scientific | 2023 |
| Cornwall Appliance Services Ltd. | Wholesale & retail | 1998 |
| Cornwall Architectural Design Ltd | Professional & scientific | 2010 |
| Cornwall Auto Technics Limited | Wholesale & retail | 2014 |
| Cornwall Carpentry and Construction Ltd | Other services | 2023 |
| Cornwall Elite External Services Limited | Construction | 2024 |
| Cornwall Estate Agents Ltd | Real estate | 2016 |
| Cornwall Haulage Ltd | Transport & logistics | 2014 |
| Cornwall Heating and Plumbing Solutions Ltd | Construction | 2016 |
| Cornwall Homestay Limited | Hospitality | 2017 |
| Cornwall International Male Choral Festival Ltd | Arts & recreation | 2002 |
| Cornwall Photography Services Ltd | Professional & scientific | 2025 |
| Cornwall Properties SW Ltd | Real estate | 2023 |
| Cornwall Shed Company Ltd | Manufacturing | 2004 |
| Cornwall Skills Ltd | Financial services | 2017 |
| Cornwall Stairs Limited | Manufacturing | 2010 |
| Cornwall Ventilation and Electrical Services Limited | Construction | 2025 |
| Cornwall Women's Fund Limited | Wholesale & retail | 2024 |
| Cornwell HR Ltd | Administrative & support | 2025 |
| Counselling Cornwall Ltd | Health & social care | 2025 |
| Countryside Contracting Limited | Administrative & support | 2013 |
| Courtwood Photographic Limited | Real estate | 2005 |
| Cousin Jack's Theatre Company CIC | Arts & recreation | 2018 |
| Cove Gardening Limited | Administrative & support | 2012 |
| Cove View (Cornwall) Management Company Limited | Households | 2019 |
| Coventry Electrics (South West) Limited | Construction | 2008 |
| Crasken Farm Wellness Lodge Holidays Ltd | Hospitality | 2024 |
| Crays Property Limited | Construction | 2009 |
| Creative Craft Workshops Ltd | Arts & recreation | 2023 |
| Creekside Residents Limited | Financial services | 2022 |
| Crendon Limited | Real estate | 2022 |
| Cres Ltd | Hospitality | 2001 |
| Crowns Solutions Ltd | Wholesale & retail | 2017 |
| Crpmr Ltd | Construction | 2025 |
| CRS Store Ltd | Wholesale & retail | 2020 |
| CST Trading C.I.C. | Hospitality | 2020 |
| CTC South West Limited | Administrative & support | 2003 |
| Cury VP Ltd | Construction | 2020 |
| D & J Bray Plumbing and Heating Limited | Construction | 2005 |
| D a Giles Limited | Construction | 2008 |
| D H Benney Limited | Agriculture & fishing | 2017 |
| D. J. Kevern Ltd | Construction | 2009 |
| DAN H Williams Limited | Health & social care | 2015 |
| Dapr Collective Limited | Manufacturing | 2010 |
| DARA7 Group - Properties Limited | Construction | 2020 |
| DARA7 Group Limited | Professional & scientific | 2020 |
| Darkstone CS Limited | Administrative & support | 2014 |
| Dave Lamb Sound Limited | Information & communication | 2026 |
| Dave Truss Plumbing & Heating Limited | Construction | 2016 |
| David Gilbert Joinery Limited | Construction | 2008 |
| Day Productions Ltd | Information & communication | 2025 |
| Daytime Cars Limited | Transport & logistics | 2019 |
| DE Lealei Consulting Limited | Professional & scientific | 2004 |
| DE Lelay Properties Limited | Real estate | 2021 |
| Deedol Ltd | Wholesale & retail | 2005 |
| Delve & Nankervis Limited | Construction | 2008 |
| Dent Sales Limited | Other services | 2014 |
| DES Dairy Limited | Agriculture & fishing | 2019 |
| DIG in Catering Ltd | Hospitality | 2024 |
| Digimix Records Limited | Information & communication | 2007 |
| Digital Detail Ltd | Information & communication | 2014 |
| Digital Dynamics Limited | Information & communication | 2019 |
| Directors Circle Ltd | Administrative & support | 2012 |
| Dive Project Cornwall CIC | Education | 2021 |
| Dixeys Group Limited | Real estate | 1993 |
| DJ Whyment Ltd | Construction | 2020 |
| DJD Homes Limited | Construction | 2007 |
| DK Complete Services Ltd | Administrative & support | 2020 |