| Diana Royal Jelly Limited | Wholesale & retail | 1989 |
| Dickey's Limited | Wholesale & retail | 2025 |
| Dieple Consulting & Training Limited | Information & communication | 2019 |
| Digital Imaging Systems Limited | Manufacturing | 2002 |
| Digital Skills Auth UK Ltd | Professional & scientific | 2023 |
| Digital Skills Authority HD Ltd | Financial services | 2024 |
| Digital Skills Authority Ltd | Professional & scientific | 2016 |
| Digital Sleuth Consulting Ltd | Information & communication | 2018 |
| Digital Studios Ltd | Professional & scientific | 2014 |
| DIGITIZE01 Ltd | Information & communication | 2019 |
| Dilveen Limited | Wholesale & retail | 2018 |
| DIN Trading & Co Limited | Wholesale & retail | 2018 |
| Dine Fusion Limited | Hospitality | 2018 |
| Dinofox Ltd | Information & communication | 2025 |
| Dins Jewellery Ltd | Other services | 2023 |
| Dips Goraya Ltd | Real estate | 2023 |
| Direct 121 Products Limited | Wholesale & retail | 2014 |
| Disruptive Ventures Limited | Professional & scientific | 2018 |
| Distinctive Directories Ltd | Information & communication | 2024 |
| Distinctive Roofing Services Ltd | Construction | 2024 |
| Distributed Energy Customer Solutions Limited | Energy | 2003 |
| Divan Shisha Lounge Ltd | Hospitality | 2024 |
| Divine Software Consultancy Services Ltd | Information & communication | 2016 |
| DJS Drains Ltd | Water & waste | 2026 |
| DMC DJ Ltd | Wholesale & retail | 2025 |
| DMG Cars Limited | Wholesale & retail | 2021 |
| Dmll Ltd | Professional & scientific | 2026 |
| DN Holdings 17 Limited | Financial services | 2025 |
| DNA Agency Limited | Arts & recreation | 2023 |
| Docslot Limited | Health & social care | 2008 |
| Docsmart Ltd | Health & social care | 2021 |
| Doctor AH Aesthetics Ltd | Health & social care | 2024 |
| Doctors Chambers (UK) Limited | Health & social care | 2011 |
| Doctors Chambers Group Limited | Professional & scientific | 2011 |
| Doctors Chambers Holdings Limited | Financial services | 2021 |
| Doctors Chambers Solutions Limited | Other services | 2010 |
| Doggie Bandannas Limited | Wholesale & retail | 2024 |
| Dominica Court Freehold Limited | Extraterritorial | 2005 |
| Domus Capital Developments Limited | Construction | 2015 |
| Donaldson Services Limited | Administrative & support | 2021 |
| Dorchester Mansions Residents Limited | Households | 2020 |
| Dorina Eagles Ltd | Administrative & support | 2022 |
| Doris London Limited | Professional & scientific | 2016 |
| Dorney Estates Limited | Real estate | 2015 |
| Dorney Events Ltd | Hospitality | 2022 |
| Dottyjack Limited | Professional & scientific | 2015 |
| Double Jack Investment Ltd | Real estate | 2019 |
| Doughglow Limited | Manufacturing | 2023 |
| Douglas Charlton Limited | Construction | 2015 |
| Dower House Residents Association (Sunninghill) Limited | Real estate | 1967 |
| Downes Holdings Limited | Other services | 2017 |
| Doyle Farming Limited | Agriculture & fishing | 2022 |
| Doyle Hire Limited | Administrative & support | 2020 |
| Doyle Machinery (Spares) Limited | Administrative & support | 2023 |
| Doyle Machinery Limited | Wholesale & retail | 2014 |
| DPO Services Limited | Information & communication | 2024 |
| DQ Associates Limited | Real estate | 2018 |
| DR Katrina Medical Aesthetics Ltd | Other services | 2026 |
| Dragonfly Gardens Design & Build Ltd | Administrative & support | 2017 |
| Dragonz Limited | Transport & logistics | 2019 |
| Drake Lodge (Amersham) Residents Management Company Limited | Households | 2020 |
| Dreamline Motors Ltd | Wholesale & retail | 2020 |
| Dreamweldtech Limited | Manufacturing | 2023 |
| DRM Engineering Limited | Information & communication | 2008 |
| Drommex Ltd | Professional & scientific | 2025 |
| Drug Safety Professionals Ltd | Health & social care | 2018 |
| Drum Opal Limited | Professional & scientific | 2023 |
| Druthers Financial Planning Limited | Financial services | 2018 |
| DRW Office Interiors Limited | Construction | 2009 |
| DS Goraya Ltd | Wholesale & retail | 2025 |
| DSG Event and Traffic Management Limited | Professional & scientific | 2022 |
| DTB Virginia Ltd | Administrative & support | 2012 |
| Dtoxid Ltd | Information & communication | 2020 |
| DU FEU Dance Limited | Arts & recreation | 2019 |
| Dubai Cars Limited | Wholesale & retail | 2018 |
| Dublin Homes Limited | Real estate | 2015 |
| Dubov Ltd | Construction | 2022 |
| Dudley Court Residents Association Limited | Households | 1965 |
| DUE South Group Limited | Energy | 2019 |
| Duffy Architects Ltd | Professional & scientific | 2020 |
| Duncflex Limited | Administrative & support | 2024 |
| Duncraig Research Consulting Limited | Professional & scientific | 2014 |
| Dunk Design Limited | Administrative & support | 2012 |
| Durbar Hospitality Limited | Hospitality | 2018 |
| Durkin Badham Ltd | Manufacturing | 2026 |
| Durkin Holdings Ltd | Construction | 2018 |
| Durline Limited | Manufacturing | 2025 |
| Duvano Ltd | Wholesale & retail | 2015 |
| Dvjones Ltd | Professional & scientific | 2018 |
| DW Machine Services Limited | Manufacturing | 2014 |
| Dynamic Glazing Ltd | Construction | 2020 |
| Dynamic Solutions (International) Limited | Administrative & support | 2000 |
| Dynamix Ltd | Wholesale & retail | 2026 |
| Dyno-Rod Limited | Other services | 1972 |
| D’Cher UK Limited | Hospitality | 2024 |
| E & Z Enterprise Limited | Real estate | 2019 |
| E Hamlet Holdings Limited | Real estate | 2010 |
| E Hamlet Property Services Limited | Real estate | 2010 |
| E&Z Estate Ltd | Real estate | 2024 |
| E.C. Care Limited | Health & social care | 2007 |