| D-Way Logistics Limited | Transport & logistics | 2025 |
| D-Way Services Ltd | Information & communication | 2017 |
| D. a. Legacy Ltd | Hospitality | 2023 |
| D. Catchesides Limited | Construction | 2002 |
| D.A.B. Renovations Limited | Construction | 2008 |
| D.A.M Records Ltd | Information & communication | 2012 |
| D.D.P. Services Limited | Construction | 1990 |
| D.E.E. Accountant Ltd | Professional & scientific | 2025 |
| D.James Properties Limited | Real estate | 2019 |
| D.L.K Electrical Contractors Ltd | Construction | 2014 |
| D.Mobi FIX Ltd | Other services | 2023 |
| D.P. Turner & Company Limited | Transport & logistics | 2002 |
| D.P.G. Advisory Services Ltd | Health & social care | 2004 |
| D11V11NE Limited | Wholesale & retail | 2020 |
| D2812 Limited | Professional & scientific | 2023 |
| D3TEM Limited | Information & communication | 2019 |
| D8A Development Limited | Information & communication | 2015 |
| D8A IT Services Ltd | Information & communication | 2021 |
| DAA London Ltd | Construction | 2023 |
| Dabs Barbering Ltd | Other services | 2025 |
| Dacya Limited | Health & social care | 2023 |
| Dairy Close Residents Company Limited | Real estate | 1999 |
| Daisy Heywood Ltd | Real estate | 2022 |
| Daiwar Limited | Construction | 1996 |
| DAK Accounting Limited | Professional & scientific | 2019 |
| DAL Bromley Ltd | Real estate | 2018 |
| Dala Ventures Ltd | Wholesale & retail | 2025 |
| Dale Construction Ltd | Construction | 2016 |
| Daley Bread Limited | Hospitality | 2011 |
| Dalkey Properties Limited | Hospitality | 2003 |
| Dalston Curve RTM Company Ltd | Households | 2025 |
| Damia Holdings Ltd | Financial services | 2024 |
| Damian Collins Consulting Limited | Administrative & support | 2024 |
| Damien Peters Holdings Limited | Financial services | 2023 |
| Damien Peters Limited | Information & communication | 2016 |
| Damnshaqs House Ltd | Professional & scientific | 2025 |
| Damon Court (Sidcup) Limited | Households | 1983 |
| DAN Academy of Science and Technology Ltd | Education | 2025 |
| DAN Scott Lighting & Media Ltd | Information & communication | 2018 |
| Danagher Rail Consultancy DRC GB Ltd | Construction | 2019 |
| Danay's Incorporated Ltd | Professional & scientific | 2025 |
| Dancefloor Collective Ltd | Arts & recreation | 2026 |
| Dandson Limited | Hospitality | 2014 |
| Dandy PIO Ltd | Professional & scientific | 2025 |
| Daneron Group Ltd. | Extraterritorial | 2018 |
| Danetworkuk Limited | Arts & recreation | 2019 |
| Dani Style Limited | Construction | 2015 |
| Daniel Alan Upcraft Limited | Administrative & support | 2015 |
| Daniel Smithson Ltd | Education | 2025 |
| Daniel Upcraft Limited | Administrative & support | 2014 |
| Danieldeco Ltd | Other services | 2015 |
| Danielle Lieu Ltd | Extraterritorial | 2017 |
| Danmar Systems Limited | Construction | 2015 |
| Danny Lane Limited | Arts & recreation | 2002 |
| Danora Atelier Ltd | Wholesale & retail | 2025 |
| Danray Estates Holdings Ltd | Real estate | 2026 |
| Dapido Ltd | Extraterritorial | 2025 |
| Dapmedia Limited | Arts & recreation | 2010 |
| Dapoani Ltd | Information & communication | 2024 |
| Daqaas Limited | Information & communication | 2023 |
| Daqhard Ltd | Manufacturing | 2024 |
| Darcy London Limited | Real estate | 2021 |
| Daria Construct Ltd | Construction | 2026 |
| Dark Blue 85 Ltd | Transport & logistics | 2019 |
| Dark Matter Roasters Limited | Wholesale & retail | 2024 |
| Daroco Limited | Construction | 2016 |
| Darren Newbound Plumbing & Heating Ltd | Construction | 2014 |
| Darshini PVT Ltd | Wholesale & retail | 2024 |
| Dart Infotech Limited | Information & communication | 2020 |
| Dart Solutions Ltd | Public administration | 2013 |
| Dartmouth Court Blackheath Ltd | Real estate | 2005 |
| Dartmouth Court Freehold Limited | Households | 2018 |
| Dartmouth Court RTM Company Limited | Real estate | 2009 |
| DAS Healthcare Providers Ltd | Health & social care | 2023 |
| Dasgupta Enterprises Ltd | Financial services | 2019 |
| Dash & Sterling Ltd | Arts & recreation | 2020 |
| Dasha (London) Limited | Real estate | 2018 |
| Data & Solution Ltd | Information & communication | 2009 |
| Datadollar Limited | Professional & scientific | 2001 |
| Dataprovider Ltd | Wholesale & retail | 2025 |
| Dataviz Holdings Ltd | Financial services | 2022 |
| Dataviz Services Ltd | Information & communication | 2018 |
| Datta Patel Property Limited | Real estate | 2025 |
| Daub & Associates Limited | Professional & scientific | 2018 |
| Daub Legal Limited | Professional & scientific | 2018 |
| Dave Benett Agency Limited | Professional & scientific | 2015 |
| Davey Jones Limited | Professional & scientific | 2008 |
| David Brook Ltd | Professional & scientific | 2016 |
| David Carruthers Associates Limited | Administrative & support | 2006 |
| David Cleary Limited | Information & communication | 2013 |
| David Thompson Trade Finance Consultant Ltd | Financial services | 2026 |
| David White Photography Limited | Professional & scientific | 2006 |
| Davidfenlon Ltd | Professional & scientific | 2019 |
| Davies Miller Services Ltd | Construction | 2012 |
| Daws Building Services Ltd | Construction | 2026 |
| DAX Brickwork Contractors Limited | Construction | 2003 |
| Day Spring Home Health Care Limited | Health & social care | 2026 |
| Daylight Homes Ltd | Real estate | 2025 |
| Daysen Foods Ltd | Manufacturing | 2026 |
| DB Castle Ltd | Financial services | 2018 |