| Data Science Partners Ltd | Information & communication | 2024 |
| DATA221 Limited | Professional & scientific | 2021 |
| Databricks IT Solutions Ltd | Information & communication | 2026 |
| Databroker Holdings Ltd | Financial services | 2024 |
| Databroker Ltd | Professional & scientific | 2009 |
| Datahuman Limited | Health & social care | 2025 |
| Datalease Limited | Professional & scientific | 2013 |
| Dataload Ltd | Information & communication | 2022 |
| Datalorian Limited | Professional & scientific | 2020 |
| Datanautics Limited | Professional & scientific | 2024 |
| Dataphonics Limited | Professional & scientific | 2023 |
| Dataq Ltd | Information & communication | 2015 |
| Datastream Insights Limited | Professional & scientific | 2019 |
| Datasys Consulting Limited | Professional & scientific | 2025 |
| Datawallet LP | | 2021 |
| Dateshare Limited | Health & social care | 1990 |
| Dave Spanovic Offshore Construction and Installation Limited | Professional & scientific | 2023 |
| Dave Thomas Limited | Arts & recreation | 1958 |
| Davenport & Co. Estates Ltd | Real estate | 2025 |
| David Baugh Ltd | Transport & logistics | 2025 |
| David Bebb Limited | Transport & logistics | 2008 |
| David Beckwith Consultancy Ltd | Extraterritorial | 2022 |
| David Berryman Holdings Limited | Wholesale & retail | 2016 |
| David Berryman Limited | Wholesale & retail | 1987 |
| David C. Smith Architects Limited | Professional & scientific | 1996 |
| David Crowley Limited | Information & communication | 2022 |
| David Hart Aerospace Pipes (Machining Division) Ltd | Extraterritorial | 2013 |
| David Hart Aerospace Pipes Limited | Manufacturing | 1999 |
| David M. Robinson Limited | Wholesale & retail | 1969 |
| David Mclean Homes (Midlands) Limited | Wholesale & retail | 1983 |
| David Mclean Homes (South West) Ltd | Wholesale & retail | 1976 |
| David Mclean Homes Limited | Wholesale & retail | 1971 |
| David Vincent Digital Limited | Professional & scientific | 2016 |
| David Yunus Gosal Neurological Services Ltd | Health & social care | 2023 |
| Davidjo Consulting Limited | Information & communication | 2016 |
| Davidson Consult Limited | Health & social care | 2015 |
| Davies & Smallwood Limited | Professional & scientific | 2002 |
| Davies Digital Ltd | Professional & scientific | 2024 |
| Dawah Pharma UK Limited | Health & social care | 2025 |
| Dawley Park Ltd | Financial services | 2024 |
| Dawn Porter Ltd | Wholesale & retail | 2018 |
| Dawson Bros. (Properties) Limited | Real estate | 1939 |
| Dawson Financial Services (UK) Limited | Professional & scientific | 2017 |
| Dawson Forte Ltd | Wholesale & retail | 2017 |
| Day Light Yacht Company Limited | Professional & scientific | 2008 |
| Daymeadow Residents Association Limited | Real estate | 1984 |
| Daystrike Ltd | Real estate | 2012 |
| Daytona Holdco Limited | Financial services | 2015 |
| Daytona Systems Limited | Professional & scientific | 2022 |
| DB CAD Services Limited | Administrative & support | 2016 |
| DB Heating and GAS Limited | Construction | 2022 |
| Dbit Limited | Information & communication | 1998 |
| DBO Private Limited | Real estate | 2019 |
| DC Beauty Enterprise Limited | Other services | 2025 |
| DCE Smiles Ltd | Health & social care | 2021 |
| DCI Global Ltd | Health & social care | 2025 |
| DCK Enterprise Ltd | Other services | 2020 |
| DCK Industrial Roofing & Cladding Limited | Construction | 2005 |
| DCL Newco Limited | Extraterritorial | 2018 |
| Ddesoftware Limited | Professional & scientific | 2018 |
| DE Martiis Bros Ltd | Hospitality | 2014 |
| DE Novo Aesthetics Ltd | Other services | 2019 |
| DE Tomaso Automobili UK Limited | Manufacturing | 2025 |
| Deacon Syme Holdings Limited | Professional & scientific | 2019 |
| Dead Cloud Ltd | Wholesale & retail | 2023 |
| Deakins Park Management Company Limited | Real estate | 1999 |
| Dealbhadh Limited | Professional & scientific | 2026 |
| Dean Flute Limited | Real estate | 2013 |
| Dean Lawrence Social Work Practice Consultancy Limited | Professional & scientific | 2024 |
| Deane IT Services Ltd | Information & communication | 2013 |
| Deano Barber Ltd | Other services | 2022 |
| Deano's Temperly Barbershop Limited | Other services | 2013 |
| Deans Water Services Limited | Administrative & support | 2008 |
| Deansgate Wealth Management Limited | Financial services | 2018 |
| Dearden Property Ltd | Real estate | 2023 |
| Debesys Holdings Ltd | Financial services | 2025 |
| Deborah J Hickling Limited | Health & social care | 2009 |
| Debt Resolution Forum | Other services | 2006 |
| Debugged Ltd | Information & communication | 2022 |
| Debuthall Limited | Households | 1985 |
| Decibel Group London Limited | Financial services | 2011 |
| Decibel Insight Limited | Information & communication | 2013 |
| Decimal Point Limited | Administrative & support | 2016 |
| Decision Systems Limited | Information & communication | 1987 |
| Declan Jacobs Barbering Kidderminster Ltd | Other services | 2025 |
| Declan Jacobs Barbering Limited | Other services | 2021 |
| Decorum Systems Limited | Information & communication | 2016 |
| Decotex Limited | Wholesale & retail | 1995 |
| Dedicated (UK) Ltd | Professional & scientific | 2005 |
| DEE Thai Limited | Hospitality | 2025 |
| DEE YE Ltd | Households | 2023 |
| DEE YEE Limited | Real estate | 2023 |
| Deel Payments UK Ltd | Information & communication | 2020 |
| Deeney Investments Limited | Real estate | 2021 |
| Deeney Media Limited | Professional & scientific | 2021 |
| Deep Dive Technology Limited | Professional & scientific | 2022 |
| Deeplook Medical Ltd | Professional & scientific | 2026 |
| Deeply Blue Limited | Professional & scientific | 2026 |
| Deepuro Limited | Financial services | 2020 |
| Deeya Investments Ltd | Real estate | 2020 |