| DDL Wealth Management Ltd. | Financial services | 2011 |
| DDN Construction Ltd | Construction | 2022 |
| DE 2D'S Limited | Health & social care | 2022 |
| DE Bastos Joinery Ltd | Construction | 2017 |
| DE Savoye Europa Ltd | Administrative & support | 2020 |
| DE Savoye Group Ltd | Professional & scientific | 2017 |
| DE Savoye Medical Concierge Ltd | Health & social care | 2017 |
| DE Savoye Medical Solutions Ltd. | Health & social care | 2020 |
| DE Villars Limited | Professional & scientific | 1926 |
| Deadtide Limited | Households | 1995 |
| Dean Cashman Psychotherapy Limited | Professional & scientific | 2020 |
| Dean Wright & Co Accounting Limited | Professional & scientific | 2025 |
| Deanna Nava Limited | Professional & scientific | 2022 |
| Deanstone Construction Limited | Wholesale & retail | 1996 |
| Deappleby Limited | Extraterritorial | 2020 |
| Dear Brothers Catering Ltd | Wholesale & retail | 2022 |
| Death of Guitar POP Limited | Information & communication | 2018 |
| DEB Banbury Limited | Administrative & support | 2010 |
| Deba Group Ltd | Wholesale & retail | 2024 |
| Debate Planet Limited | Education | 2022 |
| Debbie Wedge Limited | Professional & scientific | 2009 |
| Debco Rentals 23 Ltd | Construction | 2000 |
| Deborah Perkins Limited | Administrative & support | 2009 |
| Decastro Solutions Ltd | Construction | 2025 |
| Decibel Training Limited | Extraterritorial | 2010 |
| Decima Engineering Company Limited | Wholesale & retail | 1970 |
| Decision Calling Limited | Professional & scientific | 2023 |
| Decmir Limited | Transport & logistics | 2017 |
| Deconstruct VG Ltd | Construction | 2025 |
| Decor Repair Services Limited | Construction | 2014 |
| Decrypt DX Ltd. | Information & communication | 2018 |
| Dedham Vale Financial Services Limited | Financial services | 2019 |
| Dedicate Care Ltd | Information & communication | 2026 |
| Dedoland Ltd | Wholesale & retail | 2023 |
| Deep Focus Home Cinema Ltd | Wholesale & retail | 2022 |
| Deepdream AI Ltd | Information & communication | 2025 |
| Deerlands Day Nursery Ltd | Education | 2002 |
| Defcon Training Limited | Professional & scientific | 2013 |
| Defence Support International Limited | Wholesale & retail | 1992 |
| Defense Security Services Ltd | Administrative & support | 2024 |
| Definition Dance Ltd | Arts & recreation | 2020 |
| Definitions Hair & Beauty Studio Limited | Other services | 2010 |
| Defroand Consulting Ltd | Professional & scientific | 2019 |
| Delauney Holdings Limited | Financial services | 2026 |
| Delete Pest Control Limited | Other services | 2005 |
| Delew Consulting Limited | Professional & scientific | 2010 |
| Delgaven Pipeline Supply Limited | Transport & logistics | 1979 |
| Delight Delicious Ltd | Hospitality | 2021 |
| Delight Development Properties Ltd | Real estate | 2023 |
| Della (UK) Limited | Real estate | 2000 |
| Delman Consulting Limited | Professional & scientific | 2022 |
| Delnevo Interiors Ltd | Construction | 2019 |
| Delrem Services Limited | Other services | 2018 |
| Delta T Electrical Services Limited | Construction | 2023 |
| Delta Wealth Management (Chelmsford) Limited | Professional & scientific | 2021 |
| Delta Wealth Management Limited | Extraterritorial | 2025 |
| Deltad Consulting Limited | Professional & scientific | 2025 |
| Demimi Holdings Limited | Financial services | 2025 |
| Demir Town Ltd | Hospitality | 2017 |
| Demka Food & Wine Ltd | Wholesale & retail | 2024 |
| Denbrick Investments Limited | Financial services | 1960 |
| Denbrick Limited | Financial services | 1990 |
| Dene Care Limited | Health & social care | 2019 |
| Dengie Heating Services Ltd | Construction | 2014 |
| Dengie SWF PCN Limited | Health & social care | 2022 |
| Dengietech Ltd | Information & communication | 2013 |
| Denia Consulting Ltd | Professional & scientific | 2026 |
| Deniz Building Services Ltd | Construction | 2021 |
| Denjul UK Limited | Construction | 2022 |
| Dennis Pethers Ministries Ltd | Other services | 2014 |
| Dent Roofing Ltd | Construction | 2016 |
| Dental Waste Services Limited | Water & waste | 2018 |
| Dentalair Services (UK) Limited | Manufacturing | 2000 |
| Dentyx Ltd | Wholesale & retail | 2019 |
| Denukan Network UK BR. Ltd | Administrative & support | 2025 |
| Denward Manufacturing Limited | Manufacturing | 2000 |
| Depoha Holdings Limited | Financial services | 2025 |
| Derivative Contracts Limited | Professional & scientific | 2017 |
| Des-Daita Logistics Limited | Transport & logistics | 2024 |
| Des-Daita Services Group Limited | Water & waste | 2018 |
| Design & Contract Management (Holdings) Ltd | Professional & scientific | 2014 |
| Design & Contract Management Limited | Professional & scientific | 2004 |
| Design by Two Limited | Professional & scientific | 2020 |
| Design Consultancy U.K. Limited | Construction | 2016 |
| Design Lounge (UK) Limited | Manufacturing | 2006 |
| Design Properties Ltd | Construction | 2001 |
| Design Unboxed Ltd | Professional & scientific | 2024 |
| Designers Anonymous Limited | Information & communication | 2003 |
| Destination Care Services Ltd | Health & social care | 2025 |
| Destiny Makers Limited | Education | 2020 |
| Detail Office Solutions Limited | Administrative & support | 2007 |
| Deuteron Group Limited | Financial services | 2018 |
| Deve Limited | Professional & scientific | 1982 |
| Development Connections & Associates Limited | Professional & scientific | 2008 |
| Develovation Ltd | Construction | 2021 |
| Devenish Electrical Limited | Construction | 2026 |
| Devils Treats Ltd | Manufacturing | 2025 |
| Devines Accountants Limited | Professional & scientific | 2002 |
| Devrip Management Limited | Hospitality | 2026 |
| Devv-It Ltd | Information & communication | 2019 |