| DCH (Cornwall 1) Ltd | Construction | 2018 |
| DCH (Cornwall 2) Ltd | Construction | 2018 |
| DE Glanville Limited | Administrative & support | 2013 |
| DE Luci Park Management Company Limited | Households | 2015 |
| DE Lunch Limited | Hospitality | 2012 |
| DE Nimes Holdings Limited | Hospitality | 2019 |
| Debt Consultancy Service C.I.C. | Administrative & support | 2016 |
| Deer Park Energy Ltd | Energy | 2016 |
| Deer Park Leisure Limited | Hospitality | 2023 |
| Defender Music Limited | Information & communication | 1995 |
| Deliver Biosciences Limited | Professional & scientific | 2019 |
| Delta PHI Group Limited | Financial services | 2026 |
| Delta PHI IP Limited | Information & communication | 2026 |
| Demolition South West Ltd | Construction | 2015 |
| Demsretail Ltd | Wholesale & retail | 2025 |
| Denis MAY & Sons Limited | Manufacturing | 2006 |
| Denning Design Limited | Arts & recreation | 2007 |
| Denning Farms Ltd | Agriculture & fishing | 2014 |
| Denning/Trewithen LLP | | 2020 |
| Derma Biosciences PLC | Professional & scientific | 2023 |
| Design Room Cornwall Limited | Professional & scientific | 2010 |
| Design Unltd Limited | Information & communication | 2014 |
| Designer Systems Limited | Professional & scientific | 2009 |
| Desin Awen Limited | Professional & scientific | 2023 |
| Desmonde & Associates Ltd | Construction | 2011 |
| Desmonde Partnership Ltd | Administrative & support | 2018 |
| Destillerz Ltd | Manufacturing | 2025 |
| DEV Laxmi Ltd | Hospitality | 2024 |
| Dev-Ent Limited | Construction | 1993 |
| Devfixr Ltd | Administrative & support | 2026 |
| Devine Media Ltd | Professional & scientific | 2019 |
| Devington Court Management Company Limited | Households | 1987 |
| Devington Homes (Westward) Limited | Real estate | 2010 |
| Devon Functional Medicine LLP | | 2026 |
| Devon Healthcare Ltd | Financial services | 2017 |
| Devon Shoulder & Elbow Ltd | Health & social care | 2025 |
| Devoran Autocare Ltd | Wholesale & retail | 2010 |
| Devoran Developments Limited | Real estate | 2002 |
| Devoran Joinery Co Ltd | Manufacturing | 2010 |
| Devoran Metals Limited | Manufacturing | 1966 |
| Devoran Pre-School | Education | 2003 |
| Devren Ltd | Real estate | 2023 |
| Dhumale Events Ltd. | Hospitality | 2016 |
| Diamond & Beauty Ltd | Wholesale & retail | 2020 |
| Diamond Builders and Timber Merchants Limited | Transport & logistics | 1987 |
| Diamond Hair Design Limited | Other services | 2016 |
| DIG360 Limited | Information & communication | 2020 |
| Digital Design Labs Limited | Information & communication | 2015 |
| Dimissi Ltd | Real estate | 2024 |
| Divine Pole & Aerial Ltd | Arts & recreation | 2022 |
| Dizzy O'Dare Ltd | Arts & recreation | 2013 |
| DJW Developments Ltd | Construction | 2024 |
| DKB Construction Services Limited | Construction | 2022 |
| Dlharvey Limited | Arts & recreation | 2026 |
| DLO Holdings Limited | Professional & scientific | 2024 |
| DMB Property Development Ltd | Construction | 2025 |
| Dmcl Healthcare Ltd | Health & social care | 2024 |
| DMS Cornwall Limited | Manufacturing | 2023 |
| DMS Freehold Limited | Real estate | 2019 |
| DMS Holdings (South West) Limited | Financial services | 2018 |
| DMS Moorcroft Limited | Manufacturing | 2023 |
| DMS South Molton Limited | Manufacturing | 2023 |
| DNA Drinks Limited | Hospitality | 2014 |
| DNA Property Ltd | Real estate | 2011 |
| Dnns Solutions Ltd | Real estate | 2020 |
| Dnrb Solutions Limited | Information & communication | 2023 |
| Doananda Ltd | Health & social care | 2011 |
| Docherty Ltd | Construction | 2012 |
| Dodkins Advisory Labs Limited | Information & communication | 2025 |
| Dolton Project Limited | Construction | 2022 |
| Donaldson Jones Properties Ltd | Real estate | 2025 |
| Doublegates Management Company Limited | Households | 2005 |
| Dowling Property Management Limited | Real estate | 2024 |
| Down by the Sea Limited | Wholesale & retail | 2003 |
| Down to Earth Foundation | Education | 2008 |
| Downend Car Park Limited | Hospitality | 2016 |
| Dowra Technologies Ltd | Professional & scientific | 2024 |
| Dozmere Residents Association Limited | Households | 2011 |
| Dplp Properties Limited | Real estate | 2025 |
| DPR Offshore Ltd | Construction | 2012 |
| Dptqs Ltd | Professional & scientific | 2023 |
| DR P. Sharma Limited | Health & social care | 2012 |
| DR Healthcare Ltd | Health & social care | 2023 |
| Dracaena Apartments Limited | Hospitality | 1995 |
| Drang Holdings Limited | Wholesale & retail | 2017 |
| Driftwood Spars Ltd | Manufacturing | 2015 |
| Drilling & Workover Consultancy Services Limited | Mining & quarrying | 2005 |
| Drivenergy Ltd | Construction | 2014 |
| Driving Mobility | Other services | 1987 |
| Drone Logistics Ltd | Transport & logistics | 2024 |
| DRUMS4FUN CIC | Health & social care | 2018 |
| DRW Flooring Ltd | Construction | 2015 |
| DSW Demolition Ltd | Extraterritorial | 2023 |
| DSW Environmental Ltd | Water & waste | 2016 |
| DSW Group Holdings Ltd | Financial services | 2020 |
| DSW Skip Hire Ltd | Water & waste | 2025 |
| Duchy Business Centre Limited | Real estate | 2014 |
| Duchy Concrete Limited | Manufacturing | 2021 |
| Duchy Equine Vets Limited | Professional & scientific | 2023 |
| Duchy Glass Ltd | Construction | 2015 |