| D88 Ltd | Information & communication | 2020 |
| Dailly Investments Limited | Real estate | 2017 |
| Dalebridge Properties Limited | Real estate | 2000 |
| Dalmore Land Limited | Construction | 2015 |
| Dalton Edwards Limited | Financial services | 2013 |
| Dalton Recruitment Ltd | Administrative & support | 2019 |
| Damit Solutions Ltd | Information & communication | 2013 |
| Damson Place Management Limited | Households | 2026 |
| DAN Preston Limited | Manufacturing | 2016 |
| DAN Wood Communications Limited | Professional & scientific | 2010 |
| Dance News Limited | Information & communication | 1941 |
| Dance News Special Projects Limited | Administrative & support | 2012 |
| Daniel Holt Limited | Arts & recreation | 2021 |
| Danielle Van Cuyck Ltd | Other services | 2021 |
| Daremead Limited | Information & communication | 2017 |
| Darwin Co-Invest a LP | | 2012 |
| Dasco Trading Limited | Wholesale & retail | 2010 |
| Dash Automotive Ltd | Wholesale & retail | 2026 |
| Dash Sports Limited | Arts & recreation | 2020 |
| Dastma Limited | Wholesale & retail | 2026 |
| Data Analysis Service (D.A.S.) Ltd | Professional & scientific | 2012 |
| Data Mixx Ltd | Information & communication | 2016 |
| Data Tigme Limited | Information & communication | 2024 |
| Datawalkcouk Limited | Information & communication | 2023 |
| David Graham AU Ltd | Manufacturing | 2013 |
| David Ireland HR Solutions Limited | Other services | 2016 |
| David Lloyd Investments S2 LP | | 2010 |
| David Lloyd Investments SI LP | | 2010 |
| Dawnfine Limited | Construction | 1984 |
| DB Carnaby Ltd | Real estate | 2023 |
| DB Oxford Ltd | Real estate | 2023 |
| DB Soho Ltd | Real estate | 2023 |
| DBA Corporate Communications Limited | Professional & scientific | 2000 |
| DC50 Ltd | Information & communication | 2026 |
| DCB Landscapes Ltd | Administrative & support | 2015 |
| Ddraig Limited Partnership | | 2026 |
| DE Bathe Ltd | Education | 2016 |
| DE Mallet Morgan Limited | Professional & scientific | 2010 |
| Deborah Stead Associates Limited | Professional & scientific | 2013 |
| Debrol Limited | Wholesale & retail | 1983 |
| Decentral Technologies Limited | Information & communication | 2019 |
| Deepslate Properties Ltd | Real estate | 2025 |
| Delphi Collective Ltd | Professional & scientific | 2025 |
| Delphine Homecare Limited | Health & social care | 1999 |
| Delta Alpha Publishing Limited | Information & communication | 1998 |
| Delta Form Automotive Ltd | Manufacturing | 2025 |
| Deltatower Limited | Other services | 2013 |
| Denfit Shopfitters Limited | Administrative & support | 1993 |
| Denton & Co. Trustees Limited | Financial services | 1985 |
| Dentons Holdings PLC | Financial services | 2004 |
| Dentons Investment Services Limited | Financial services | 2000 |
| Dentons Pension Management Limited | Financial services | 1989 |
| Dermato Logical Limited | Manufacturing | 2007 |
| Design Build Enhance Limited | Construction | 2020 |
| Design Intent Ltd | Construction | 2013 |
| Design LAB Solutions Limited | Information & communication | 2016 |
| DESIGN7UK Limited | Manufacturing | 2026 |
| Deuchar Consulting Limited | Professional & scientific | 2010 |
| Devoto Limited | Professional & scientific | 2005 |
| DFB Commerce Limited | Wholesale & retail | 2023 |
| DG Nice Move Ltd | Transport & logistics | 2011 |
| DGS Capital Partners LLP | | 2016 |
| DGX Consulting Services Ltd | Professional & scientific | 2025 |
| Diamond Grill Ltd | Hospitality | 2019 |
| Diamond Lead Films Limited | Information & communication | 2025 |
| Diamond Nails HA Limited | Other services | 2025 |
| Digital Distilla Limited | Professional & scientific | 2015 |
| Digital First Capital LLP | | 2025 |
| Digital Resolutions Limited | Information & communication | 2007 |
| Digital Sign Services Limited | Manufacturing | 2001 |
| Digital Super Glue Limited | Information & communication | 2012 |
| Dilan Ltd | Construction | 2020 |
| Dimond Bikes UK Limited | Professional & scientific | 2014 |
| Dinefwr Systems Ltd | Transport & logistics | 2017 |
| Direct Property Assets Limited | Real estate | 2020 |
| Direction International Ltd | Manufacturing | 2024 |
| Dive Deep Events Limited | Professional & scientific | 2026 |
| DJW Plumbing & Heating Ltd | Construction | 2013 |
| DK Plumbing and Building Services Ltd | Construction | 2026 |
| DMP Media Limited | Information & communication | 2021 |
| DNL Finance Limited | Professional & scientific | 2026 |
| Dobson Developments Limited | Construction | 2011 |
| Dog Days Holdings Ltd | Other services | 2025 |
| Domaines Bournet-Lapostolle UK Limited | Agriculture & fishing | 2022 |
| Donation Tech Solutions Ltd | Information & communication | 2023 |
| Donovan & Co.(Barges)Limited | Real estate | 1934 |
| Doric Developments Europe LLP | | 2007 |
| DOT Duff Media Ltd | Information & communication | 2010 |
| DOT Origin Ltd | Information & communication | 1997 |
| DOT Sign Language Limited | Education | 2010 |
| Dough Culture Ltd | Professional & scientific | 2020 |
| Dove House Interiors & Exteriors Ltd | Construction | 2019 |
| Dovetail Language Services Ltd | Professional & scientific | 2015 |
| Download Education Ltd | Education | 2013 |
| Download Learning Ltd | Education | 2015 |
| DPJ City Limited | Information & communication | 2019 |
| DPM Legal Services Limited | Other services | 2012 |
| DPS 45 Limited | Arts & recreation | 2020 |
| DR Alice Martell Limited | Health & social care | 2015 |
| DR C Smile and Aesthetics Limited | Financial services | 2022 |