| Davies Properties Exeter Ltd | Real estate | 2025 |
| DAW Bathrooms and Kitchens Ltd | Construction | 2016 |
| Dawes Electricians Ltd | Energy | 1983 |
| Dawlish Business Park Management Company Limited | Real estate | 2014 |
| Dawlish Skip Hire Limited | Water & waste | 2010 |
| Dawn Holdings | Professional & scientific | 1988 |
| Dayjay Ltd | Wholesale & retail | 2025 |
| Daykin Morgan Medical Ltd | Health & social care | 2024 |
| Daylight Music Productions Ltd | Manufacturing | 2011 |
| Daynes Farm Limited | Agriculture & fishing | 2018 |
| DB Luxury Cars Limited | Wholesale & retail | 2018 |
| DB Production Services Ltd | Administrative & support | 2014 |
| Dbax Ltd | Information & communication | 2022 |
| DC Design Works Ltd. | Professional & scientific | 2014 |
| DC Ground Construction Ltd | Administrative & support | 2024 |
| DC Space & Storage Solutions Ltd | Manufacturing | 2017 |
| DC Trading (SW) Limited | Wholesale & retail | 2015 |
| DCA Properties SW Ltd | Real estate | 2024 |
| Dcisive Leadership Limited | Professional & scientific | 2015 |
| Dcla Holdings Limited | Financial services | 2025 |
| Dcrr Dog Fields LP | | 2023 |
| DCS Plumbing Limited | Construction | 2017 |
| DCW Polymers Limited | Manufacturing | 2023 |
| DDC Lake Ltd | Information & communication | 2012 |
| DDF Fire Ltd | Construction | 2019 |
| DDL Property Investments Limited | Real estate | 2018 |
| Ddmh Developments Limited | Financial services | 2020 |
| Ddsg Properties Ltd | Real estate | 2026 |
| Ddtr Farming Limited | Agriculture & fishing | 2026 |
| Ddtr Limited | Water & waste | 2023 |
| Ddtr Potatoes Ltd | Agriculture & fishing | 2024 |
| Dean Forge (Holdings) Limited | Financial services | 2010 |
| Dean Forge Fabrications Limited | Manufacturing | 2011 |
| Dean Forge Limited | Manufacturing | 2002 |
| Dean Thorne Ltd | Professional & scientific | 2014 |
| Deanbreyley Ltd | Professional & scientific | 2013 |
| Deane Vale Motors Ltd | Wholesale & retail | 2013 |
| Deanos Flowers Ltd | Wholesale & retail | 2008 |
| Deanpark Logistics Limited | Transport & logistics | 2019 |
| Debonair Ventures Ltd | Wholesale & retail | 2023 |
| Deborah Samuel Coaching Ltd. | Professional & scientific | 2019 |
| Debra Holland Ltd | Professional & scientific | 2012 |
| Debtlink Limited | Professional & scientific | 1991 |
| Decision Insight Hub Limited | Information & communication | 2000 |
| Decision Insight Information Group (UK) Limited | Information & communication | 1987 |
| Deck Law Limited | Professional & scientific | 2024 |
| Decor Rooms Group Ltd | Manufacturing | 2020 |
| Decorum Care & Support Services Limited | Health & social care | 2014 |
| Dedicated Delivery Solutions Ltd | Transport & logistics | 2010 |
| DEE Plattinum Property Ltd | Real estate | 2022 |
| Deea Cris Ltd | Transport & logistics | 2019 |
| Deep Moor LF Limited | Water & waste | 1991 |
| Deepa International Ltd | Wholesale & retail | 2024 |
| Deer Deli Investments Ltd | Real estate | 2023 |
| Deer View Fisheries Ltd | Agriculture & fishing | 2025 |
| Degee Limited | Professional & scientific | 2016 |
| Degould Limited | Manufacturing | 2011 |
| Dekor Kitchens Limited | Construction | 2018 |
| Delacy Limited | Construction | 2020 |
| Delaford Property Consultants Limited | Real estate | 2026 |
| Delcor Upholstery Limited | Manufacturing | 2024 |
| Delivery Multitask Limited | Wholesale & retail | 2025 |
| Delve Mining Solutions Limited | Mining & quarrying | 2022 |
| Demarque International Ltd | Information & communication | 2000 |
| Demczuk Transport Ltd | Transport & logistics | 2025 |
| Dementia Counselling Ltd | Extraterritorial | 2022 |
| Demeter Systems Limited | Professional & scientific | 2023 |
| Deni Dlin Limited | Construction | 2025 |
| Denis & Andrei Flatbread Cafe Ltd | Hospitality | 2025 |
| Denis Wright Limited | Manufacturing | 1941 |
| Denleys Automobilia Ltd | Wholesale & retail | 2023 |
| Denmark Court Management Company (Exeter) Limited | Households | 1974 |
| Dennis James & Co Limited | Real estate | 2009 |
| Dent Business Consulting Ltd | Professional & scientific | 2018 |
| Dent Repair Service SW Ltd | Wholesale & retail | 2022 |
| Dentalogica Ltd | Professional & scientific | 2023 |
| Dentcure Ltd | Wholesale & retail | 2015 |
| Denthouse Trading Ltd | Wholesale & retail | 2020 |
| Dentivm Limited | Health & social care | 2025 |
| Denton Williams Ltd | Professional & scientific | 2006 |
| DEP23 Ltd | Hospitality | 2019 |
| Derived Effect Ltd | Manufacturing | 2024 |
| Dermalogical Ltd | Health & social care | 2024 |
| Dermaworks Cornwall Limited | Health & social care | 2024 |
| Dermelle Aesthetics Ltd | Health & social care | 2025 |
| Dermix Consultancy Ltd | Health & social care | 2026 |
| Dersim Grill (SW) Ltd | Hospitality | 2019 |
| Desert Hare Limited | Wholesale & retail | 2021 |
| Design & Construct SW Limited | Construction | 2022 |
| Design and Integrate Ltd | Information & communication | 2011 |
| Design by FOX Ltd | Professional & scientific | 2022 |
| Design for Today Ltd. | Information & communication | 2016 |
| Design Review Ltd | Professional & scientific | 2008 |
| Design Review West Ltd | Extraterritorial | 2019 |
| Design the New Limited | Information & communication | 2015 |
| DESIGN42 Ltd | Construction | 2014 |
| Designamite Ltd | Professional & scientific | 2003 |
| Designers Down South Limited | Information & communication | 2015 |
| Designers in Space Community CIC | Information & communication | 2023 |
| Designers UP North Ltd | Information & communication | 2013 |