| Chromacon UK Limited | Manufacturing | 2018 |
| Church Garage (Plymouth) Limited | Wholesale & retail | 2012 |
| Church Park Properties Ltd | Construction | 2025 |
| Churchtown Drive Road Management Ltd | Households | 2026 |
| Cisw Property Limited | Real estate | 2019 |
| City Style Limited | Other services | 2018 |
| CKW Property Services Ltd | Households | 2023 |
| Clean Team Plymouth Ltd | Administrative & support | 2023 |
| Cleanforce Plymouth Limited | Administrative & support | 2012 |
| Cloudbase Digital Limited | Information & communication | 2022 |
| Clovis Homes Limited | Real estate | 2016 |
| Coast Communications & Marketing Ltd | Professional & scientific | 2005 |
| Coastal Wraps Ltd | Construction | 2025 |
| Coastline Group South West Limited | Construction | 2022 |
| Codfather's (Saltash) Limited | Hospitality | 2010 |
| Colour Distribution Ltd | Wholesale & retail | 2013 |
| Columba Health Care Services Ltd | Health & social care | 2017 |
| Community Enterprises PL12 CIC | Professional & scientific | 2006 |
| Complete HQ Limited | Professional & scientific | 2019 |
| Composite Integration Ltd | Manufacturing | 2002 |
| Compusoft Business Software Ltd | Extraterritorial | 2013 |
| Concept Brickwork SW Ltd | Construction | 2019 |
| Concept Construction SW Ltd | Construction | 2024 |
| Connect Utilities SW Ltd | Construction | 2023 |
| Cornelle Communications Limited | Professional & scientific | 2011 |
| Cornerstone Developments Southwest Ltd | Construction | 2024 |
| Cornish Cleaners Ltd | Other services | 2025 |
| Cornish Construction Consultancy Ltd | Construction | 2025 |
| Cornish Harbour House Limited | Professional & scientific | 2025 |
| Cornwall Offroad South West Ltd | Wholesale & retail | 2025 |
| Coryton Arms Limited | Hospitality | 2019 |
| Cosgrove Construction (Cornwall) Limited | Wholesale & retail | 2003 |
| County Mortgages (Cornwall) Ltd | Financial services | 2020 |
| Courtvollard Estates Limited | Real estate | 1993 |
| Coxco Holdings Limited | Financial services | 2014 |
| Coxcocapital Limited | Financial services | 2023 |
| Cozium Ltd | Wholesale & retail | 2024 |
| Creative Direction IG Limited | Professional & scientific | 2016 |
| Crest Property Maintenance Ltd | Construction | 2025 |
| Crimetag Limited | Professional & scientific | 2013 |
| Critch H Developments Limited | Construction | 2026 |
| Crylla Valley Management Company Limited | Households | 2021 |
| CSF Recruitment and Logistics Limited | Administrative & support | 2019 |
| CSP Promotions Limited | Extraterritorial | 2001 |
| CSS Surveying Ltd | Professional & scientific | 2011 |
| Cubs Day Nursery and PRE School Ltd | Education | 2025 |
| CZH Properties Limited | Real estate | 2022 |
| D & C Commercials Ltd | Wholesale & retail | 2025 |
| D&G Performance Gym Ltd | Other services | 2021 |
| D&S Lewis Limited | Information & communication | 2025 |
| Daass Limited | Financial services | 2022 |
| Daisy Chain Trading Ltd | Professional & scientific | 2024 |
| Dart Developments (Pengover) Limited | Construction | 2022 |
| Dart Developments Ltd | Construction | 2021 |
| Dartana Ltd | Professional & scientific | 2014 |
| Dato Properties Ltd | Construction | 2023 |
| David Brown Plymouth Ltd | Other services | 2004 |
| David Francis Consultancy Ltd | Professional & scientific | 2026 |
| David Stitson Ltd | Health & social care | 2011 |
| DB Autos Ltd | Wholesale & retail | 2006 |
| DB Autos Southwest Ltd | Wholesale & retail | 2025 |
| DB Valeting and Detailing Ltd | Administrative & support | 2023 |
| Dcvac Group Ltd | Construction | 2018 |
| Dead Hand Records Ltd | Arts & recreation | 2025 |
| Deakin Construction SW Ltd | Construction | 2025 |
| Delecto Marketing Limited | Information & communication | 2011 |
| Deltor Holdings Limited | Financial services | 2016 |
| Department of Wellbeing Ltd | Health & social care | 2015 |
| Design & Safety Limited | Professional & scientific | 2007 |
| Devon & Cornwall Maintenance Solutions Ltd | Construction | 2015 |
| Devon Ventures Ltd | Professional & scientific | 2025 |
| Diamond Nails (Saltash) Ltd | Other services | 2022 |
| Diamond Nails (ST Austell) Ltd | Other services | 2023 |
| Digital Fashion Framework Ltd | Information & communication | 2020 |
| Diorama Days Limited | Professional & scientific | 2018 |
| DIY Media Group Ltd | Professional & scientific | 2022 |
| DM Assets Ltd | Real estate | 2020 |
| Dm-Xtech UK Ltd | Professional & scientific | 2024 |
| DMY Ltd | Wholesale & retail | 2022 |
| Done Right Driveways Ltd | Extraterritorial | 2026 |
| Done Right SW Ltd | Construction | 2016 |
| Doneright Plastering and Building Limited | Construction | 2024 |
| Dragonfly Interiors Ltd | Professional & scientific | 2019 |
| Drb@Uxb Ltd | Transport & logistics | 2014 |
| DSC Scaffolding & Waste Ltd | Water & waste | 2020 |
| Duchy Car Sales Limited | Wholesale & retail | 2021 |
| Duchy Lettings Limited | Real estate | 2022 |
| Duchy Property Services Ltd | Real estate | 2023 |
| Duncan House (Saltash) Limited | Households | 2020 |
| Dxrbystudios Ltd | Wholesale & retail | 2021 |
| Dynamic Branding Ltd | Professional & scientific | 2023 |
| Dynamic Marine Consultancy Ltd | Professional & scientific | 2026 |
| DZL Risk and Resilience Ltd | Administrative & support | 2025 |
| Earthcoat Ltd | Construction | 2019 |
| Eastgate Engravers Ltd | Wholesale & retail | 2010 |
| Eclectic Interiors (Plymouth) Ltd | Wholesale & retail | 2017 |
| Eco Roofing 2025 Limited | Construction | 2025 |
| Eco-Nexus Engineering Ltd | Professional & scientific | 2024 |
| Ecobuildsupplies Ltd | Extraterritorial | 2009 |
| Ecovest Ltd | Professional & scientific | 2022 |