| Dumont Trading Limited | Real estate | 2017 |
| Dumpay Ltd | Wholesale & retail | 2025 |
| Dumped Stock Ltd | Wholesale & retail | 2021 |
| Dumpling Creative Ltd | Professional & scientific | 2024 |
| Dunalastair Hotel Limited | Hospitality | 2016 |
| Dunamis Care Services Ltd | Health & social care | 2017 |
| Dunamis Management Consultancy Limited | Professional & scientific | 2017 |
| Dunamis Management Ltd | Administrative & support | 2025 |
| Dunamis Solutions Limited | Administrative & support | 2023 |
| Dunbar Capital Projects Limited | Construction | 1997 |
| Dunbar Education Recruitment Limited | Administrative & support | 2016 |
| Dunbar Properties Limited | Real estate | 2026 |
| Dunbar West Limited | Arts & recreation | 2021 |
| Dunber Estates Limited | Real estate | 2024 |
| Dunchurch Engineering Limited | Professional & scientific | 2010 |
| Dundam Healthcare Limited | Health & social care | 2016 |
| Dundashill 4B Limited | Construction | 2025 |
| Dundee & Dundee Limited | Extraterritorial | 2021 |
| Dundee Chambers Assets Limited | Real estate | 2023 |
| Dundee Chambers LP | | 2023 |
| Dundee Chemicals Limited | Extraterritorial | 2004 |
| Dundee George GP LLP | | 2025 |
| Dundee George LP | | 2025 |
| Dundee George Nominees Limited | Real estate | 2025 |
| Dundee High Street LP | | 2025 |
| Dundee Telephone Assets Limited | Real estate | 2024 |
| Dundonald Property Management Limited | Households | 2023 |
| Dunewall Ltd | Real estate | 2022 |
| Dunfair Media Limited | Manufacturing | 2025 |
| Dunfine Limited | Construction | 1973 |
| Dunford Limited | Administrative & support | 2015 |
| Dungannon LP | | 2020 |
| Dunham GAP Projects Ltd | Construction | 2022 |
| Dunham Mews (Management Company) Limited | Households | 1982 |
| Dunham Mews Limited | Construction | 2015 |
| Dunham Property Management Limited | Real estate | 2016 |
| Dunham Residential Ltd | Real estate | 2024 |
| Dunhams Accountants Ltd | Extraterritorial | 2008 |
| Dunhams Audit Ltd | Extraterritorial | 2008 |
| Dunhams Consultants Limited | Extraterritorial | 2015 |
| Dunhams Financial Planning Limited | Financial services | 1988 |
| Dunhams Financial Services Limited | Extraterritorial | 2016 |
| Dunhams Investments Limited | Financial services | 2003 |
| Dunhams Limited | Professional & scientific | 2024 |
| Dunhil Constructions Ltd | Construction | 2021 |
| Dunhill Ltd. | Manufacturing | 2024 |
| Dunhill Systems Ltd | Information & communication | 2022 |
| Dunkil Developments Limited | Construction | 2007 |
| Dunlop Extrusions Limited | Extraterritorial | 2001 |
| Dunlop Industries Limited | Professional & scientific | 2005 |
| Dunlop Property Group Limited | Real estate | 2025 |
| Dunn AC (Midlands) Limited | Manufacturing | 2018 |
| Dunn Family Holdings LLP | | 2024 |
| Dunne Holdings Ltd | Wholesale & retail | 2026 |
| Dunnehl Ltd | Professional & scientific | 2011 |
| Dunning Deals Limited | Wholesale & retail | 2026 |
| Dunnsmoor Property Management Limited | Professional & scientific | 2005 |
| Dunn’S River Restaurants Ltd | Hospitality | 2019 |
| Dunraf Labs Ltd | Wholesale & retail | 2024 |
| Dunree Properties Limited | Real estate | 2025 |
| Dunsmore Hall Limited | Hospitality | 2016 |
| Dunsmore Hall Management Limited | Hospitality | 2016 |
| Dunsmure Road Estates Ltd | Real estate | 2019 |
| Dunston Dunfermline Nominees Limited | Real estate | 2022 |
| Dunston GP LLP | | 2022 |
| Dunston Livingston Nominees Limited | Real estate | 2022 |
| Dunston LP | | 2022 |
| Dunyyas Ltd | Real estate | 2024 |
| DUO Creative Services Limited | Information & communication | 2005 |
| DUO Delivery Ltd | Transport & logistics | 2025 |
| DUO Packaging Group Limited | Manufacturing | 2014 |
| DUO Plastics Limited | Manufacturing | 1988 |
| DUO Wellness Ltd | Other services | 2024 |
| Duoba Developments Ltd | Construction | 2019 |
| Duoban Consultancy Limited | Administrative & support | 2017 |
| Duoessens Ltd | Wholesale & retail | 2024 |
| Duolabz Limited | Information & communication | 2026 |
| Duologiq Ltd | Information & communication | 2026 |
| Duomi Group Limited | Wholesale & retail | 2025 |
| Duovision Ltd | Information & communication | 2025 |
| Dupoin UK Ltd | Financial services | 2014 |
| DUR Tailor Ltd | Manufacturing | 2020 |
| Dura Ace Plumbing & Heating Ltd | Construction | 2021 |
| Dura Hose and Fittings Limited | Wholesale & retail | 1984 |
| Durand Investments Ltd | Real estate | 2024 |
| Durban Design Studio Ltd | Professional & scientific | 2018 |
| Durfield Limited | Real estate | 1988 |
| Durgan and Ashworth Dental Care Limited | Health & social care | 2007 |
| Durgo Ltd | Hospitality | 2024 |
| Durham Assets 1 Limited | Real estate | 2026 |
| Durham Assets Limited | Real estate | 2026 |
| Durham Data Solutions Limited | Information & communication | 2026 |
| Durham Estates (Ukco) Limited | Real estate | 2022 |
| Durham Flap Course Ltd | Health & social care | 2010 |
| Durham Real Estates (NO2) Limited | Real estate | 2018 |
| Durham Real Estates Ltd | Real estate | 2018 |
| Durjaya Limited | Real estate | 2023 |
| Durling Street Investments Limited | Real estate | 2005 |
| Durnford Financial Management Ltd | Administrative & support | 2017 |
| Durnford Ltd | Real estate | 2021 |