| DM Consultants Limited | Professional & scientific | 2021 |
| DM Electrical Installations & Testing Services Ltd | Construction | 2023 |
| DM Informatics Ltd | Information & communication | 2015 |
| Dmaa Sports Ltd | Wholesale & retail | 2018 |
| DMC Plymouth Ltd | Construction | 2018 |
| DMH Services (South West) Ltd | Construction | 2015 |
| Dmipi Limited | Real estate | 2005 |
| DMS Wrangaton Motors Ltd | Wholesale & retail | 2012 |
| Dmse Limited | Arts & recreation | 2016 |
| Dmsn Ltd | Real estate | 2019 |
| DMT 8 Limited | Transport & logistics | 2020 |
| DMW Plumbing and Heating Ltd | Construction | 2021 |
| DNB Tattoo Limited | Other services | 2010 |
| DNH Construction Limited | Construction | 2002 |
| DNK-Z2H Ltd | Information & communication | 2025 |
| DNS Construction Solutions Limited | Construction | 2023 |
| DO IT UP Ltd | Construction | 2019 |
| Doane AG Ltd | Hospitality | 2025 |
| Dobson's Group Limited | Wholesale & retail | 2019 |
| Dockmate UK & Ireland Ltd | Wholesale & retail | 2024 |
| Dockside Marine Services Ltd | Manufacturing | 2026 |
| Doddridge Properties Limited | Real estate | 2026 |
| Dodi Enterprise Ltd | Manufacturing | 2012 |
| Dog Walker Plymouth Limited | Other services | 2025 |
| Doggieexpress Limited | Transport & logistics | 2026 |
| Dollface Beauty & Aesthetics Ltd | Other services | 2021 |
| Dollhouse Academy Limited | Education | 2020 |
| Dolls Tanning Creams Plymouth Limited | Manufacturing | 2025 |
| Dolphin Drones Ltd | Professional & scientific | 2026 |
| Dolphin Hotel Property Limited | Real estate | 2015 |
| Dolphin House (Southampton) Limited | Professional & scientific | 2002 |
| Dolphin House Student Accommodation Ltd | Real estate | 2024 |
| Dolphin Owners RTM Company Limited | Households | 2013 |
| Dolphin Quay Holdings Limited | Real estate | 2017 |
| Domicly Properties UK Ltd | Real estate | 2025 |
| Dominora Group Ltd | Wholesale & retail | 2025 |
| Domus Letting and Management Ltd | Real estate | 2018 |
| Domus Property and Construction Consultants Ltd | Professional & scientific | 2017 |
| Donacia Ltd | Real estate | 2019 |
| DONGSHENG88 Limited | Hospitality | 2026 |
| Donnington Estate Agent Group Ltd | Administrative & support | 2019 |
| Donnington Family Partnership LLP | | 2022 |
| Donny Wear Ltd | Wholesale & retail | 2020 |
| Door and Window Solutions SW Ltd | Construction | 2019 |
| Doorcare South West Limited | Construction | 2003 |
| Doors and Windows Limited | Manufacturing | 1983 |
| Doorstep Property Management Limited | Households | 2014 |
| Dorcas Media Ltd | Professional & scientific | 2013 |
| Dorey & Lawson Limited | Agriculture & fishing | 1929 |
| Dosky Kebab Ltd | Hospitality | 2023 |
| DOT9 Ideas Ltd | Professional & scientific | 2018 |
| Dottee Limited | Information & communication | 2016 |
| Dotty Rose Limited | Wholesale & retail | 2013 |
| Double a Professional Limited | Wholesale & retail | 2018 |
| Double Diamond Brewery Limited | Other services | 2013 |
| Dougalldevelopments Ltd | Real estate | 2019 |
| Dousland Langford Ltd | Other services | 2026 |
| Dousland Livgreen Ltd | Other services | 2026 |
| Dousland Ltd | Real estate | 2026 |
| Dousland-Thergis Ltd | Financial services | 2026 |
| Dove Court (Paignton) Management Company Limited | Households | 2010 |
| Dowma Holdings Ltd | Information & communication | 2025 |
| Down 2 Earth Services (SW) Limited | Water & waste | 2026 |
| Doyen Voss Ltd | Administrative & support | 2020 |
| DP Construction & Interiors Ltd | Construction | 2019 |
| DP Developments SW Limited | Construction | 2024 |
| DPB Rail Ltd | Construction | 2018 |
| DPG One Ltd | Real estate | 2023 |
| Dplusd Ltd | Construction | 2015 |
| DPM Plympton Ltd | Extraterritorial | 2019 |
| DPS Construction Ltd | Construction | 2017 |
| DPS Electrical SW Ltd | Construction | 2021 |
| DPW Design Ltd | Professional & scientific | 2018 |
| DPW Media Design Ltd | Professional & scientific | 2022 |
| DPW Retail Ltd | Wholesale & retail | 2012 |
| DPW Wellington Limited | Hospitality | 2025 |
| DR C J Burrell Ltd | Health & social care | 2015 |
| DR Cassie JO Evans Limited | Health & social care | 2024 |
| DR Colin Jones Grants Limited | Professional & scientific | 2011 |
| DR Colin Jones Limited | Health & social care | 2020 |
| DR Cool Ltd | Construction | 2023 |
| DR Hot Ltd | Wholesale & retail | 2018 |
| DR Jessica Calf Ltd | Health & social care | 2025 |
| DR Mohamed Medcare Ltd | Health & social care | 2025 |
| DR Russell Shobrook & Associates Ltd | Education | 2023 |
| DR Sarah Psychology Ltd | Health & social care | 2022 |
| Dragon MSK Imaging Ltd | Health & social care | 2022 |
| Dragon Property Initiatives Ltd | Households | 2024 |
| Dragonhtakeaway Ltd | Wholesale & retail | 2024 |
| Drain Care (South West) Ltd. | Water & waste | 1995 |
| Drain Sense Group Ltd | Water & waste | 2026 |
| Drake Circus Limited | Real estate | 2015 |
| Drake Court Limited | Households | 1983 |
| Drake Homecare Limited | Health & social care | 2012 |
| Drake Logistics Limited | Wholesale & retail | 2023 |
| Drake Medical Alliance Limited | Health & social care | 2015 |
| Drake Mill Car Sales Ltd | Administrative & support | 2025 |
| Drake Projects Ltd | Real estate | 2021 |
| Drake Property Ltd | Households | 2023 |
| Drake Rentals Ltd | Administrative & support | 2025 |