| Dacol Services (UK) Limited | Construction | 1977 |
| Dainton Self Store Limited | Professional & scientific | 2002 |
| Dakada Developments Limited | Construction | 2007 |
| Daniel Group Holdings Limited | Professional & scientific | 1984 |
| Dart Abbey Glastonbury Limited | Real estate | 2022 |
| Dart Abbey Poole Limited | Construction | 2022 |
| Dart Financial Advice Ltd | Financial services | 2007 |
| Dart Mortgages Limited | Financial services | 2007 |
| Dart Plumbing & Heating (Southwest) Ltd | Construction | 2018 |
| Dart Sensors Limited | Manufacturing | 1994 |
| Dartington Trading Company Limited(The) | Wholesale & retail | 1975 |
| Dartmoor Estates & Property Management (Sales) | | 1994 |
| Dartmoor Photographic Limited | Manufacturing | 2003 |
| Dartmoor Windows and Conservatories Limited | Construction | 2004 |
| Dartside Paintworks Limited | Manufacturing | 2024 |
| Dash Direct Limited | Wholesale & retail | 2001 |
| Dasped Ltd | Administrative & support | 2021 |
| Data Disk (U.K) Limited | | 1983 |
| Dave Chapman Carpets & Flooring Limited | Construction | 2003 |
| Dave Johnson Limited | Construction | 2003 |
| Dave Pollard Transport Limited | Transport & logistics | 2002 |
| David Roche Geoconsulting Limited | Professional & scientific | 2001 |
| David Youll Hair Designers Ltd | Other services | 2003 |
| Davis Developments (SW) Limited | Construction | 2005 |
| Daydream Holidays Ltd | Hospitality | 2005 |
| Daydreams Travel Limited | Administrative & support | 1987 |
| DBD Construction Limited | Construction | 2007 |
| Dcms (Construction) Limited | | 1988 |
| Deafid Ltd | Transport & logistics | 2018 |
| Dealdrive Limited | Professional & scientific | 2004 |
| Deep Blue Sound Limited | Education | 1998 |
| Deep Network Ltd | Administrative & support | 2009 |
| Deka Contracting Ltd | Other services | 2023 |
| Denis Brinicombe Group Limited | Agriculture & fishing | 2001 |
| Denis Brinicombe Limited | Professional & scientific | 1979 |
| Dental & Implant Centre Ltd | Health & social care | 2007 |
| Denvern Limited | Transport & logistics | 2003 |
| Desets Ltd | Transport & logistics | 2020 |
| Detox Yogi Ltd | Health & social care | 2006 |
| Devon & Cornwall Surfacing Ltd | Administrative & support | 2006 |
| Devon & Somerset Flight Training Ltd | Arts & recreation | 2005 |
| Devon Air Ambulance Trading Company Limited | Transport & logistics | 1999 |
| Devon and Cornwall Refugee Support | Health & social care | 2007 |
| Devon Bedstead Company Ltd | Manufacturing | 2025 |
| Devon Bookkeeping Solutions Limited | Professional & scientific | 2023 |
| Devon Cakes Limited | Wholesale & retail | 2005 |
| Devon Chiropractic Clinic Ltd | Health & social care | 2006 |
| Devon Ecobuild Limited | Construction | 2007 |
| Devon Farm Catering Butchers Limited | Transport & logistics | 1987 |
| Devon Foods Limited | Agriculture & fishing | 2001 |
| Devon Forestry Consultants Limited | Agriculture & fishing | 2015 |
| Devon Grain (Services) Limited | Agriculture & fishing | 1983 |
| Devon House Maintenance Company Limited | Real estate | 1988 |
| Devon Oak Traditional Foods Limited | Transport & logistics | 1991 |
| Devon Payroll Solutions Limited | Extraterritorial | 2023 |
| Devon Power Services Ltd | Energy | 2015 |
| Devon Real Estate Limited | Real estate | 2023 |
| Devon Street Food Limited | Hospitality | 2010 |
| Devon Tax Solutions Limited | Extraterritorial | 2023 |
| Devon Thatching Ltd | Construction | 2005 |
| Devon Vineyards Ltd | Agriculture & fishing | 2007 |
| Devon Wildlife Enterprises Limited | Professional & scientific | 1990 |
| Devon Wildlife Trust | Other services | 1962 |
| DG Catering Services Ltd | Hospitality | 2023 |
| Dick Oliver Limited | Arts & recreation | 1980 |
| Diespeker (Interiors) Limited | Construction | 2002 |
| Digitel Technology Ltd | Wholesale & retail | 1997 |
| Dinan Garage Limited | Wholesale & retail | 2003 |
| Dionilife Nominees Limited | Financial services | 2025 |
| Direct Electrical Contractors Limited | Construction | 1999 |
| Dirty Duck Limited | Hospitality | 2007 |
| Discovery Software Ltd | Information & communication | 2002 |
| Dittisham Boat Hire Ltd | Administrative & support | 2015 |
| Dmqa Limited | Other services | 2022 |
| Dolphin Court Shaldon Management Company Limited | Real estate | 1981 |
| Donkey World Limited | Wholesale & retail | 2002 |
| Douglas Victor House Management Company Limited(The) | Households | 1985 |
| Doveleigh Care Limited | Hospitality | 2000 |
| Dragonfly Foods Holdings Limited | Manufacturing | 2025 |
| Dragoon Limited | Real estate | 2003 |
| Drakesmead Management (Tavistock) Limited | Hospitality | 2006 |
| Droppa & Droppa Limited | Manufacturing | 2003 |
| DUE South Limited | Professional & scientific | 1999 |
| Dukes of Sidmouth Limited | Professional & scientific | 2004 |
| Duncan Research & Development Ltd | Manufacturing | 1998 |
| Dunrell Limited | | 1985 |
| Dura Manufacturing Limited | Manufacturing | 2007 |
| Duralight (South West) Limited | Construction | 1987 |
| Duratherm Limited | Real estate | 1979 |
| Durrant Hotel Limited | Hospitality | 2003 |
| DW Health & Wellness Limited | Other services | 2025 |
| E. J. Gifford Limited | Professional & scientific | 1982 |
| E.C. Jones Limited | Manufacturing | 2001 |
| E.D.S. Developments Limited | Other services | 1995 |
| E.H.B.P.T. Enterprises Limited | Real estate | 2002 |
| Eagle Country Exhibitions | | 1992 |
| Eagle Timber Projects Limited | Construction | 2004 |
| East Avercombe Farm Limited | Agriculture & fishing | 2003 |
| East Devon Car Breakers Limited | Wholesale & retail | 1985 |
| East Prawle Festival Ltd | Arts & recreation | 2026 |