| Connell Accountants Limited | Administrative & support | 2015 |
| Connolly Cornwall Limited | Real estate | 2022 |
| Consistently Social Ltd | Professional & scientific | 2022 |
| Cook Belacevic Haffner and Partners Limited | Professional & scientific | 2021 |
| Cool Earth Action | Health & social care | 2007 |
| Corff Ystwyth Ltd | Health & social care | 2011 |
| Corker Media Limited | Information & communication | 2023 |
| Cornish Blacksmiths Collective C.I.C. | Education | 2024 |
| Cornish Dream Charters Limited | Transport & logistics | 2012 |
| Cornish Glass Art Limited | Arts & recreation | 2020 |
| Cornish Holiday Rentals Ltd | Hospitality | 2019 |
| Cornish Lithium PLC | Mining & quarrying | 2016 |
| Cornish Maid Ltd | Hospitality | 2011 |
| Cornish Paws Veterinary Practice Ltd | Professional & scientific | 2017 |
| Cornish Property Holdings Limited | Financial services | 2023 |
| Cornish Property Rentals Ltd | Real estate | 2005 |
| Cornish Road Transport and Haulage Ltd | Extraterritorial | 2021 |
| Cornish Service Co. Ltd | Administrative & support | 2025 |
| Cornish Shore Ltd | Hospitality | 2020 |
| Cornish Skips Ltd | Extraterritorial | 2021 |
| Cornish Tugboat Ltd | Wholesale & retail | 2008 |
| Cornwall Cabs Ltd | Transport & logistics | 2018 |
| Cornwall Erecting Services Ltd | Construction | 2010 |
| Cornwall Exterior Cleaning Ltd | Administrative & support | 2026 |
| Cornwall Film Festival | Information & communication | 2004 |
| Cornwall Flat Roofing UK Company Limited | Construction | 2006 |
| Cornwall Gateway CIC | Wholesale & retail | 2023 |
| Cornwall Homes Limited | Construction | 2025 |
| Cornwall Passenger Services Limited | Transport & logistics | 2023 |
| Cornwall Plus Limited | Hospitality | 2012 |
| Cornwall Surfacing and Groundworks Ltd | Construction | 2025 |
| Cornwall Zinc Roofing Limited | Construction | 2017 |
| Country Tradition Limited | Manufacturing | 1988 |
| Cove Construction (SW) Limited | Construction | 2005 |
| CP Nail Supplies Limited | Other services | 2019 |
| CR Electronics Limited | Other services | 2017 |
| Crafty Beer Seller Limited | Wholesale & retail | 2016 |
| Craigentinny Dental Care Limited | Health & social care | 2011 |
| Cream Cornwall Trading Ltd | Wholesale & retail | 2020 |
| Credability Productions Limited | Real estate | 2014 |
| Creo Cabinet Makers Ltd | Construction | 2010 |
| Crtestar Ltd | Administrative & support | 2022 |
| Crystal Services Sussex Ltd | Transport & logistics | 2020 |
| Cultivating Connections Cornwall CIC | Education | 2026 |
| Custom CAP Company Ltd | Wholesale & retail | 2026 |
| CUT by Beam Limited | Professional & scientific | 2020 |
| Cutting Edge (Hairdressing) Limited | Other services | 2002 |
| Cycle Solutions the Falmouth Bike Shop Ltd. | Manufacturing | 2001 |
| D & K Golf Ltd | Arts & recreation | 2020 |
| D & T Motors Gweek Limited | Wholesale & retail | 2025 |
| D & T Motors Limited | Wholesale & retail | 2019 |
| D Bunn Joinery Limited | Construction | 2017 |
| D G B Masonry Limited | Construction | 2016 |
| D L a L Limited | Construction | 2021 |
| D3LIVERY Ltd | Information & communication | 2018 |
| Daaku Foods Ltd | Hospitality | 2025 |
| Dalla Triga Limited | Administrative & support | 2024 |
| Dalriada Books Limited | Information & communication | 2007 |
| Dandy Technology Ltd | Wholesale & retail | 2021 |
| Daniell Court Management Company Limited | Households | 1989 |
| Dapple & DOT Ltd | Manufacturing | 2022 |
| Dart Architecture Limited | Professional & scientific | 2020 |
| Dartmoor Diner Limited | Hospitality | 2004 |
| David Carne (Sales) Limited | Wholesale & retail | 1979 |
| David COX Marine Surveyors and Consultants Limited | Professional & scientific | 2002 |
| David Doran Illustration Ltd | Arts & recreation | 2016 |
| Defiance Music CIC | Arts & recreation | 2025 |
| Dehaus Ltd | Wholesale & retail | 2018 |
| Delmo Limited | Hospitality | 2000 |
| Denspire Ltd | Professional & scientific | 2025 |
| Dental World Cornwall Ltd. | Health & social care | 2010 |
| Desertoak Limited | Construction | 1986 |
| Devoted to Dachshunds Limited | Wholesale & retail | 2014 |
| DH Auto Southwest Ltd | Wholesale & retail | 2021 |
| Diablito Development Ltd | Information & communication | 2018 |
| Digification Ltd | Professional & scientific | 2021 |
| Digitally Developed Limited | Wholesale & retail | 2014 |
| Discount Mobility Limited | Extraterritorial | 2010 |
| DJ in Cornwall Ltd | Information & communication | 2011 |
| DL Electrical & GAS Services SW Limited | Construction | 2022 |
| Dolvean Management Company Limited | Households | 1999 |
| Doogle Holdings Limited | Financial services | 2019 |
| Dorset Emergency Placement Services Ltd. | Health & social care | 2018 |
| Dowling Dodd Property Services Limited | Professional & scientific | 2005 |
| Downwind Management Consultancy Limited | Professional & scientific | 2015 |
| DP Industrial Services & Supplies Ltd | Wholesale & retail | 2023 |
| Dualgym Ltd | Other services | 2025 |
| Dunelm Safety Cornwall Ltd | Professional & scientific | 2021 |
| Dyad Investment Company Limited | Wholesale & retail | 2021 |
| E&R KG Ltd | Hospitality | 2020 |
| Eagles Engraving Ltd | Real estate | 2014 |
| Eastwood Garage Limited | Wholesale & retail | 2002 |
| EAT Drink Love Cornwall Limited | Wholesale & retail | 2025 |
| Ecological Lighting Solutions Ltd | Professional & scientific | 2022 |
| Elegant Homes and Estates Limited | Real estate | 2019 |
| Elite Render Solutions Ltd | Construction | 2025 |
| Embassy Media Ltd | Information & communication | 2020 |
| Emily Settle Design Ltd | Professional & scientific | 2020 |
| Emma Stacey Limited | Professional & scientific | 2014 |
| EMN Staffing Group Limited | Hospitality | 2018 |