| D&D of Medway Limited | Construction | 2024 |
| D'Art Building Consultants Limited | | 1985 |
| D.I.P.P. Limited | Real estate | 2007 |
| D.J.R Management Services Limited | Professional & scientific | 2017 |
| D2 Corporate Development Limited | Professional & scientific | 2018 |
| D3NETWORK Limited | Information & communication | 2011 |
| D4N Detailing Ltd. | Wholesale & retail | 2016 |
| DA Design Studio Ltd | Professional & scientific | 2019 |
| DAB Advisory Ltd | Professional & scientific | 2022 |
| DAF Solutions Ltd | Information & communication | 2021 |
| Dagan Services Ltd | Professional & scientific | 2013 |
| Dahlquist LLP | | 2025 |
| Dahlstrom UX Consulting Limited | Information & communication | 2011 |
| Daily Bread (Rusthall) Ltd | Hospitality | 2013 |
| Daisy Ashton Design Limited | Administrative & support | 2025 |
| Daisypoppy Properties Limited | Real estate | 2004 |
| DAJ Consultancy Ltd | Professional & scientific | 2024 |
| Dalby Real Estate Ltd | Real estate | 2021 |
| Dale & Simpson Limited | Professional & scientific | 2015 |
| Dali Investments Ltd | Real estate | 2022 |
| Damasach Limited | Financial services | 2021 |
| Damhurst Ltd | Administrative & support | 2016 |
| DAN George Communications Limited | Administrative & support | 2012 |
| DAN Transporter Ltd | Transport & logistics | 2020 |
| Dancing PIN Holdings Limited | Financial services | 2026 |
| Dandara South East Limited | Construction | 2020 |
| Daniel Green Fitness Limited | Health & social care | 2017 |
| Daniel J Boyes Limited | Real estate | 2019 |
| Danielsix Limited | Construction | 2025 |
| Daniil Magerov Ltd | Arts & recreation | 2025 |
| Danimak F M Limited | Construction | 2009 |
| Danish Living (London Road) Limited | Real estate | 2022 |
| Danish Living (Polegate) Limited | Real estate | 2023 |
| Danish Living (Ridgedown) Limited | Real estate | 2026 |
| Danish Living Limited | Other services | 2013 |
| Danish Living Properties Limited | Real estate | 2022 |
| Danob IT Consultancy Limited | Information & communication | 2019 |
| Dapop Logistics Ltd | Transport & logistics | 2019 |
| Darby Digital Limited | Information & communication | 2021 |
| Darcy & Co Consulting Ltd | Professional & scientific | 2019 |
| Dark Pyre Interactive Limited | Information & communication | 2018 |
| Darkhorse Brand Consulting Ltd | Professional & scientific | 2015 |
| Darley PCM Limited | Other services | 2010 |
| Darren Hughes Limited | Administrative & support | 2008 |
| Darryl Curcher Photography & Events Ltd | Professional & scientific | 2012 |
| Dart Projects Limited | Professional & scientific | 2022 |
| Darwin Clayton (UK) Limited | Financial services | 1993 |
| Darwin Clayton Limited | Financial services | 1978 |
| Dastec Consulting Limited | Administrative & support | 2010 |
| Data Flare Solutions Limited | Information & communication | 2022 |
| Data Physics (UK) Limited | Manufacturing | 1973 |
| DATAH2O Ltd | Information & communication | 2023 |
| Datahelix Limited | Information & communication | 2011 |
| Datalinx Labelling Ltd. | Other services | 2008 |
| Datametrics Ltd | Professional & scientific | 2012 |
| Date App Ltd | Information & communication | 2020 |
| DAV Logistics Ltd | Transport & logistics | 2019 |
| Dave Frost Ltd | Information & communication | 2023 |
| Dave Wild Design Limited | Professional & scientific | 2019 |
| Davella Ltd | Information & communication | 2023 |
| Davey Lamp Limited | Administrative & support | 2005 |
| David Haugh Ltd | Manufacturing | 2005 |
| David Hill Construction Ltd | Construction | 2019 |
| David L E Davis Ltd | Information & communication | 2024 |
| David Thomas Media Limited | Professional & scientific | 2008 |
| David Toole Roofing Limited | Construction | 2003 |
| David Turfitt Limited | Professional & scientific | 2015 |
| David Williams Contract Services Limited | Financial services | 2008 |
| Davis Care Limited | Health & social care | 2004 |
| Davstock Limited | Extraterritorial | 2022 |
| Davut GUL Bespoke and Alteration Ltd | Manufacturing | 2021 |
| Day Construction Consulting Ltd | Professional & scientific | 2024 |
| Dayba Limited | Information & communication | 2007 |
| DB Financial Ltd | Financial services | 2007 |
| DB Gardens Ltd | Administrative & support | 2018 |
| DC Camera and Vision Ltd | Information & communication | 2022 |
| DC Psychiatric Services Ltd | Health & social care | 2017 |
| DC Steel Finance Ltd | Professional & scientific | 2026 |
| DC Wilson & Associates Ltd | Professional & scientific | 2018 |
| DCN Property Investments Limited | Real estate | 2023 |
| Dcrose Property Consultants Ltd | Real estate | 2022 |
| DCX Agent AI Ltd | Administrative & support | 2026 |
| Ddly Limited | Information & communication | 2016 |
| Ddxor UK Limited | Information & communication | 2024 |
| DE Carteret Accounting Ltd | Professional & scientific | 2023 |
| DE Vere Auctions Ltd | Wholesale & retail | 2024 |
| DE Winter House Limited | Households | 2011 |
| Deacon CAD Ltd | Construction | 2012 |
| Deacon Securities Limited | Real estate | 1983 |
| Dean Evans Translations Ltd | Professional & scientific | 2021 |
| Dean Hanley Consulting Limited | Professional & scientific | 2026 |
| Dean Vipond Design Services Ltd | Information & communication | 2022 |
| Dear Lisa Limited | Other services | 2025 |
| Dear Prudence Ltd | Professional & scientific | 2023 |
| Deba Engineering Ltd | Construction | 2016 |
| Debbie Hayes HR Ltd | Administrative & support | 2021 |
| Deben Bioprocess Limited | Professional & scientific | 2026 |
| Debonair Social Club Limited | Information & communication | 2022 |
| Debra Price Associates Limited | Education | 2015 |
| Decentralised Media Ltd | Professional & scientific | 2025 |