| Dominantalex Limited | Administrative & support | 2023 |
| Domnick Hunter Fabrication Limited | Professional & scientific | 1986 |
| Domnick Hunter Group Limited | Professional & scientific | 1989 |
| Domnick Hunter Limited | Professional & scientific | 1963 |
| Domus Wealth Management Ltd | Administrative & support | 2024 |
| Don'T Fomo Ltd | Wholesale & retail | 2022 |
| Donald Heating & Plumbing Services Limited | Construction | 2023 |
| Donald Quest Services Limited | Wholesale & retail | 2020 |
| Doodle Juice Ltd | Information & communication | 2025 |
| Doorphones Services Limited | Administrative & support | 1992 |
| Dorenisa Ltd | Other services | 2024 |
| Dormer Grab Services Ltd | Water & waste | 2018 |
| DOT Dash Consultancy Limited | Professional & scientific | 2023 |
| DOT Glasses International Ltd | Manufacturing | 2022 |
| Dotch Flavour Foods Ltd | Hospitality | 2026 |
| Dotcom Estate Ltd | Real estate | 2025 |
| Dott Consultancy Ltd | Information & communication | 2019 |
| Double H Logistics Limited | Manufacturing | 2026 |
| Doug's Property Services Ltd | Construction | 2019 |
| Doughdynasty Ltd | Hospitality | 2025 |
| Douglas Road and Prairie Road Residents Association Limited | Households | 2006 |
| Dovecon Limited | Construction | 2023 |
| Doves Care Agency Ltd | Other services | 2016 |
| Dower Mews Management Limited | Administrative & support | 1988 |
| Down to a Tea Limited | Real estate | 2016 |
| Downham BR1 Management Limited | Households | 2006 |
| Doyle CAD Services Ltd | Professional & scientific | 2010 |
| DP Consulting Ltd | Information & communication | 2025 |
| DPL Properties Limited | Real estate | 2020 |
| Dppc Ltd | Professional & scientific | 2023 |
| DPS Investments Ltd | Real estate | 2026 |
| DPW Ltd | Other services | 2020 |
| DR Coaching Limited | Administrative & support | 2009 |
| DR Results Limited | Education | 2018 |
| Draeger Medical UK Limited | Manufacturing | 2001 |
| Drain Busters Watford Ltd | Administrative & support | 2024 |
| Drawing OUT Potential Limited | Professional & scientific | 2017 |
| Drax Film Two Ltd | Information & communication | 2024 |
| Drax Productions Ltd | Information & communication | 2022 |
| Drayton Bird Associates Limited | Administrative & support | 2004 |
| Drayton Property Management Company Limited | Households | 2019 |
| Dream Rentals Ltd | Transport & logistics | 2021 |
| Dream Salad Media Ltd | Information & communication | 2026 |
| Dream Supplies Ltd | Wholesale & retail | 2022 |
| Dreams Homes Ltd | Construction | 2013 |
| Dreams Living Care Ltd | Health & social care | 2024 |
| Dreamweaver Entertainments Ltd | Wholesale & retail | 2016 |
| Dreamworx Group Ltd | Information & communication | 2024 |
| Dreen Consultancy Limited | Wholesale & retail | 2010 |
| Dress UP Fashion Ltd | Wholesale & retail | 2025 |
| Drift Limits Ltd | Arts & recreation | 2013 |
| Drift Limits Performance Limited | Wholesale & retail | 2015 |
| Drilistone Ruci UK Ltd | Manufacturing | 2023 |
| Dripcycle Ltd | Wholesale & retail | 2025 |
| Driply Ltd | Health & social care | 2025 |
| Drive 25 Ltd | Transport & logistics | 2014 |
| Drive and Protect Limited | Transport & logistics | 2003 |
| Driveauto Ltd | Education | 2020 |
| Driveon Automotive Limited | Wholesale & retail | 2025 |
| Driver Experience Ltd | Transport & logistics | 2022 |
| Driver Services Network Limited | Information & communication | 2012 |
| Drone Building Inspection and Surveying Services Ltd. | Professional & scientific | 2021 |
| Dronestu" Drone Surveying Services Limited | Professional & scientific | 2024 |
| DRR Salons Limited | Administrative & support | 2021 |
| Drumfire Consulting Limited | Professional & scientific | 2024 |
| Drumgoon Contracts Limited | Professional & scientific | 2022 |
| Drunken Turtle Ltd | Wholesale & retail | 2021 |
| Drussel Consulting Limited | Professional & scientific | 2012 |
| DRV Electrics Ltd | Construction | 2025 |
| Dryliquid Ltd | Hospitality | 2026 |
| DS Home Textiles Ltd | Wholesale & retail | 2026 |
| DSC Heating Limited | Construction | 2020 |
| DSF Consultant Services Limited | Professional & scientific | 2013 |
| Dshh Electrical Ltd | Construction | 2022 |
| DSI Rail Limited | Construction | 2014 |
| Dsm-Donna Ltd | Administrative & support | 2016 |
| DSP Oak Limited | Wholesale & retail | 2026 |
| DSP Retail Limited | Wholesale & retail | 2018 |
| Dsvp Advisors Limited | Professional & scientific | 2024 |
| Dtab Neuro Ltd | Health & social care | 2025 |
| Dtlr Ltd | Wholesale & retail | 2026 |
| DTM Classics Limited | Wholesale & retail | 2019 |
| DTM Tyres Limited | Wholesale & retail | 2007 |
| Dtol Landscaping and Construction Ltd | Administrative & support | 2024 |
| DTP Group Ltd | Administrative & support | 2026 |
| Duchess & Butler Ltd | Hospitality | 2015 |
| Dudley Property and Estates Limited | Real estate | 2020 |
| DUDU91 Limited | Construction | 2018 |
| Duesbury Place Management Company Limited | Households | 2002 |
| Dukes International Ltd | Professional & scientific | 2023 |
| DULL2BRIGHT Glazing Services Ltd | Construction | 2024 |
| Duna General Builders Ltd | Construction | 2019 |
| Dunfield Developments Ltd | Construction | 2016 |
| Dunlop Aerospace Group Limited | Professional & scientific | 1998 |
| Dunlop Aerospace Holdings Limited | Professional & scientific | 1998 |
| Dunlop Aerospace Limited | Extraterritorial | 1960 |
| Dunlop Aerospace Overseas Investments Limited | Extraterritorial | 1998 |
| Dunlop Aerospace Overseas Limited | Professional & scientific | 1998 |
| Dunlop Holdings Limited | Professional & scientific | 1896 |
| Dunlop Limited | Professional & scientific | 1970 |