| D&C Investors Group Ltd | Professional & scientific | 2022 |
| D&D FIX Limited | Construction | 2018 |
| D&D Services London Ltd | Other services | 2019 |
| D'Argent Ltd | Arts & recreation | 2017 |
| D-Tec Performance Engineering Limited | Administrative & support | 2008 |
| D. & J. Winton Limited | Wholesale & retail | 1973 |
| D. Rose Planning LLP | | 2015 |
| D.A. Psychology Ltd | Education | 2025 |
| D.B.M Pro Trans Ltd | Transport & logistics | 2018 |
| D1 Hand Car Wash Ltd | Wholesale & retail | 2024 |
| D3 Chauffeur Ltd | Transport & logistics | 2022 |
| D3 Construction Limited | Construction | 2020 |
| DA Vinci's Dreams Limited | Professional & scientific | 2015 |
| Daah Properties Limited | Real estate | 2016 |
| DAB Hold Co Limited | Information & communication | 2023 |
| Dabas Health Care Limited | Health & social care | 2019 |
| Dabee & Co. Ltd | Wholesale & retail | 2023 |
| DAG Housing Ltd | Administrative & support | 2026 |
| DAI Consulting Ltd | Professional & scientific | 2016 |
| Daisy London Home Ltd | Wholesale & retail | 2023 |
| Dale Properties Limited | Real estate | 2008 |
| Dalmage Active Ltd | Public administration | 2019 |
| Dalmaine Ltd | Information & communication | 2021 |
| DAM Catering Limited | Hospitality | 2010 |
| DAN Harler Electrical Ltd | Construction | 2016 |
| DAN Williams Photography Limited | Administrative & support | 2015 |
| Dan's Solutions Ltd | Construction | 2019 |
| Dancle Distribution Ltd | Manufacturing | 2012 |
| Danesbridge Interiors Ltd | Wholesale & retail | 2023 |
| Danesh Communications Limited | Professional & scientific | 2014 |
| Daniel Hill Professional Shop Limited | Arts & recreation | 2017 |
| Danny Collins Productions Limited | Information & communication | 2001 |
| Danny Simpson Academy Ltd | Education | 2026 |
| Danny Simpson Limited | Other services | 2013 |
| Danson Motors Limited | Wholesale & retail | 2012 |
| DAP Enterprises Ltd | Information & communication | 2023 |
| Daphne Foods Ltd | Hospitality | 2019 |
| Dar-E-Abbas CIC | Health & social care | 2021 |
| Daria's Hospitality Limited | Hospitality | 2014 |
| Darik Limited | Transport & logistics | 2011 |
| Darklight Art Ltd | Professional & scientific | 2020 |
| Darne PT Limited | Arts & recreation | 2026 |
| Darren Strowger Limited | Financial services | 2008 |
| Dashvelle Private Limited | Real estate | 2024 |
| Data Disposal Limited | Administrative & support | 2017 |
| Data Mandala Limited | Administrative & support | 2025 |
| Datadestruction Ltd | Administrative & support | 2019 |
| DATAMIG4U Ltd | Information & communication | 2024 |
| Datasearch Services Limited | Administrative & support | 1976 |
| Daty Limited | Real estate | 2025 |
| Dauksa Ltd | Financial services | 2012 |
| Dauth Limited | Professional & scientific | 2015 |
| DAV Building Ltd | Construction | 2017 |
| Dava RES Ltd | Financial services | 2024 |
| Davenfive Group Limited | Construction | 2025 |
| Davenfive Holdings Limited | Financial services | 2025 |
| Davenfive Limited | Construction | 2023 |
| Davenheath Security Limited | Construction | 2023 |
| David & Andrew Limited | Administrative & support | 2025 |
| David Driscoll Limited | Construction | 1977 |
| Davids N Davids Ltd | Real estate | 2016 |
| Davis Hand and Dual Controls Limited | Wholesale & retail | 2001 |
| Dawngame Limited | Wholesale & retail | 1988 |
| Day Real Estate Limited | Real estate | 2026 |
| Daydrmr Ltd | Administrative & support | 2025 |
| Daymac Group Ltd | Administrative & support | 2019 |
| Daymac London Ltd | Administrative & support | 2019 |
| DBK Designs Limited | Construction | 2009 |
| Dbsr Limited | Real estate | 2015 |
| DC Workflow Ltd | Construction | 2021 |
| DCB Consultancy Ltd | Administrative & support | 2025 |
| DCL Group Services Limited | Construction | 2022 |
| DD Essex Ltd | Wholesale & retail | 2026 |
| DE Lacy Figaji Limited | Health & social care | 2025 |
| DE Silva Property Management Ltd | Hospitality | 2025 |
| DE Vere Court RTM Company Limited | Households | 2021 |
| Deacons Consultant Limited | Administrative & support | 2016 |
| Dealer Link Recruitment Limited | Administrative & support | 2026 |
| Dealpraise Limited | Arts & recreation | 1992 |
| Dean Perry Property Limited | Real estate | 2022 |
| Dean UK LLP | | 2009 |
| Deanplan Limited | Real estate | 1969 |
| Deanway Construction Limited | Construction | 2010 |
| Debbie Louise Performing Arts Limited | Arts & recreation | 2014 |
| Debbies Events Limited | Arts & recreation | 2017 |
| Debbridge Holdings Limited | Real estate | 2008 |
| Deborah Julie Sampson Ltd | Extraterritorial | 2022 |
| Decipha C.I.C. | Education | 2005 |
| Deckett Investments Limited | Real estate | 1952 |
| Decomo UK Limited | Construction | 1999 |
| Deen Property Corporation Ltd | Real estate | 2025 |
| Deep in Dentine Limited | Health & social care | 2022 |
| Deepspur Limited | Administrative & support | 2006 |
| Defined Holdings Ltd | Financial services | 2022 |
| Defined Interiors Ltd | Construction | 2017 |
| Defix Global Limited | Wholesale & retail | 2021 |
| Deli Twist Ltd | Hospitality | 2012 |
| Delight at the END of the Tunnel Ltd | Manufacturing | 2025 |
| Delilah Property Management Ltd | Administrative & support | 2017 |
| Deltarite Commercial Ltd | Manufacturing | 1997 |