| Dashora Property Ltd | Real estate | 2025 |
| Data Cable Installs Limited | Information & communication | 2012 |
| Data Centre Partners Limited | Information & communication | 2013 |
| Data Controls and Analytics Services Limited | Information & communication | 2021 |
| Data Dumps Ltd | Information & communication | 2025 |
| Data Protection Management Consultants Ltd | Professional & scientific | 2025 |
| Data Scrub Ltd | Administrative & support | 2012 |
| Data Wave Technologies Limited | Information & communication | 2017 |
| Databox Technologies Limited | Information & communication | 2018 |
| Dataforms Chartered Press Limited | Manufacturing | 1965 |
| Dataforms Limited | Manufacturing | 1964 |
| Dataprov Limited | Information & communication | 2021 |
| Datatropy Limited | Information & communication | 2023 |
| David Cassettari Ltd | Information & communication | 2015 |
| David Priestley Limited | Wholesale & retail | 2024 |
| David Smith GAS Installations Limited | Construction | 2019 |
| David Wingfield & Associates Ltd | Professional & scientific | 2013 |
| David's.House Limited | Real estate | 2025 |
| Davosh Limited | Real estate | 2020 |
| Dawn Court Limited | Households | 2016 |
| Dawn Pharma Group Ltd | Administrative & support | 2016 |
| DAWN2DUST Cleaning Services Ltd | Administrative & support | 2023 |
| Dawnline Media Limited | Information & communication | 2025 |
| Dazzlin Daizy Ltd. | Manufacturing | 2008 |
| DC Graphic Design Limited | Manufacturing | 2002 |
| DCC Civils Ltd | Construction | 2026 |
| DCL Developments Ltd | Construction | 2015 |
| DCM Property Maintenance Limited | Administrative & support | 2010 |
| Dcrypt.Digital Ltd | Professional & scientific | 2015 |
| DD Collections Limited | Administrative & support | 2025 |
| DD Group Limited | Construction | 2015 |
| DDH Recruiting Ltd | Administrative & support | 2024 |
| DE Castro Property Group Ltd | Real estate | 2022 |
| DE Electrical Solutions Limited | Construction | 2018 |
| Debora Brockwell Associates Limited | Professional & scientific | 2002 |
| Deceo Ltd | Construction | 2011 |
| Deckhouse (Sevenoaks) Ltd | Hospitality | 2022 |
| Deckhouse (Taunton) Limited | Hospitality | 2022 |
| Deckhouse Ltd | Hospitality | 2021 |
| Decorated Tables Ltd | Extraterritorial | 2016 |
| DEE Nails Limited | Other services | 2024 |
| Dee's Enterprise Limited | Health & social care | 2012 |
| Deebriel Limited | Real estate | 2019 |
| Deegan & Sons Ltd | Extraterritorial | 2024 |
| Deem Team Ltd | Hospitality | 2018 |
| DEFINITION1013 Ltd | Professional & scientific | 2025 |
| Deji & Kola Limited | Wholesale & retail | 2022 |
| Delco Services Bromley Ltd | Manufacturing | 2025 |
| Deleshos and Sons Ltd | Hospitality | 2021 |
| Delexity Ltd | Professional & scientific | 2021 |
| Delight of India Ltd | Hospitality | 2025 |
| Delights Care Limited | Health & social care | 2025 |
| Delree Training and Consultancy Ltd | Professional & scientific | 2022 |
| Delta Enterprises Group Limited | Other services | 2023 |
| Delta Theta Alpha Limited | Administrative & support | 2012 |
| Delta WCS Limited | Administrative & support | 2021 |
| Deluxe Residential Ltd | Real estate | 2018 |
| Delvitas Ltd | Transport & logistics | 2018 |
| Delyiks Ltd | Health & social care | 2011 |
| DEM Entertainment Limited | Arts & recreation | 2025 |
| Demiraj Construction Services Ltd | Construction | 2023 |
| Demler Aesthetics and Beauty Ltd | Health & social care | 2025 |
| Demo London Ltd | Wholesale & retail | 2023 |
| Demot Services Ltd | Wholesale & retail | 2024 |
| Dempsey Construction Ltd | Construction | 2011 |
| Dencare Clinic Limited | Health & social care | 2018 |
| Denco Waterproofing Ltd | Construction | 2024 |
| Denimist UK Ltd | Wholesale & retail | 2022 |
| Dennehy Wealth Limited | Financial services | 1980 |
| Denstel Limited | Transport & logistics | 2018 |
| Derefred Limited | Professional & scientific | 2025 |
| Design & Management Air Conditioning & Mechanical Services Limited | Construction | 1994 |
| Design Aesthete Ltd | Wholesale & retail | 2020 |
| Detailing Apex Projects Ltd | Wholesale & retail | 2026 |
| Detecho Ltd | Wholesale & retail | 2021 |
| DEV Leopard Housing Limited | Households | 2018 |
| DEV Leopard Ltd | Information & communication | 2014 |
| Developers Connect Limited | Real estate | 2021 |
| Devil's Detailing Ltd | Wholesale & retail | 2022 |
| Devine & Co (London) Ltd | Wholesale & retail | 2025 |
| Dexion (SE) Limited | Construction | 2015 |
| DF Elevators Ltd | Construction | 2022 |
| DG Chauffuer Services Limited | Transport & logistics | 2017 |
| DG Projects Group Ltd | Construction | 2025 |
| DG Sims Limited | Real estate | 2023 |
| DGM Express Ltd | Transport & logistics | 2023 |
| DH Building Projects Ltd | Construction | 2022 |
| DH Clamp Consulting Limited | Administrative & support | 2012 |
| Dhathri Homes Limited | Real estate | 2021 |
| Dhudi Investments Limited | Hospitality | 2025 |
| Diagon Fire Protection Ltd | Construction | 2022 |
| Diamond Steel Solutions Ltd | Construction | 2019 |
| Diandro Chef's Limited | Hospitality | 2022 |
| Dibbinsdale Brook Views Project Ltd | Real estate | 2025 |
| Different Colour Property Services Ltd. | Real estate | 2005 |
| Digidel Ltd | Information & communication | 2019 |
| Digital Alchemy Hub Ltd | Professional & scientific | 2024 |
| Digital Business Tech Limited | Information & communication | 2024 |
| Digital Sourcing Limited | Administrative & support | 2020 |
| Digital Wealth Ltd | Wholesale & retail | 2024 |