| Darwich Management Services Limited | Manufacturing | 2025 |
| Darworld Ltd | Wholesale & retail | 2020 |
| Data Witchery Ltd | Information & communication | 2020 |
| Datamede Limited | Real estate | 2001 |
| Dataweaving Ltd | Information & communication | 2019 |
| David Clive Ochonogor Contract Services Ltd | Administrative & support | 2018 |
| Davon Project Services Limited | Professional & scientific | 2014 |
| Davron Estates Limited | | 1971 |
| Dawley Resources Ltd | Real estate | 2026 |
| Dawn Counselling Ltd | Health & social care | 2021 |
| Dawn Hodge Associates Limited | Professional & scientific | 2000 |
| Day Consultancy Ltd | Information & communication | 2022 |
| Dayadevi Ltd | Health & social care | 2020 |
| Dayyan Properties Ltd | Real estate | 2024 |
| Dazni Global Limited | Administrative & support | 2025 |
| DB Auto Consultancy Limited | Wholesale & retail | 2015 |
| DB Enviro Ltd | Administrative & support | 2025 |
| DB96 Ltd | Construction | 2023 |
| DBC Global Holdings Limited | Financial services | 2026 |
| DBR Associates (UK) Limited | Extraterritorial | 2004 |
| DC Dwellings Ltd | Real estate | 2023 |
| DCD Law Ltd | Professional & scientific | 2021 |
| Dcosta Holdings Limited | Real estate | 2025 |
| DCS Medical Services Limited | Professional & scientific | 2012 |
| DD & Sons 68 Ltd | Real estate | 2023 |
| DDC Roofing Ltd | Construction | 2021 |
| Ddhp Build & Design Limited | Construction | 2025 |
| De-Lam Limited | Water & waste | 2026 |
| De-Tach Limited | Information & communication | 2023 |
| Dead Brave Limited | Wholesale & retail | 2023 |
| Deal Hubb Ltd | Wholesale & retail | 2025 |
| DEAL2BUILD Limited | Administrative & support | 2017 |
| Dean Court Garston Residents Limited | Households | 1987 |
| Dear Matcha Ltd | Wholesale & retail | 2025 |
| Debs Properties Ltd | Real estate | 2025 |
| DECIDE99 Ltd | Information & communication | 2026 |
| Decor Trader Limited | Other services | 2011 |
| Decor Wholesale Limited | Wholesale & retail | 2023 |
| Decorium Bespoke Interiors Ltd | Manufacturing | 2024 |
| Dedicated Drivers (London) Ltd | Transport & logistics | 2020 |
| DEE ZEE Ventures Ltd | Wholesale & retail | 2026 |
| Deecon Consulting Limited | Administrative & support | 2020 |
| Deehan Properties Ltd | Households | 2020 |
| Deen Signs Ltd | Wholesale & retail | 2023 |
| Deep Balconies Ltd | Manufacturing | 2021 |
| Deep Contractors Ltd | Construction | 2010 |
| Deep Equity London Ltd | Real estate | 2024 |
| Deep Food and Wine Limited | Wholesale & retail | 2011 |
| Deep GRC London Ltd | Construction | 2020 |
| Deep GRC Plant Hire Ltd | Administrative & support | 2022 |
| Deep Group London Ltd | Construction | 2020 |
| Deep Investment London Ltd | Financial services | 2023 |
| Deep Living Great Kimble Ltd | Real estate | 2025 |
| Deep Living Kenley Limited | Construction | 2025 |
| Deep Living London Ltd | Construction | 2009 |
| Deep Living Warlingham Limited | Construction | 2024 |
| Deep London Ltd | Wholesale & retail | 2020 |
| Deep Remedials Ltd | Construction | 2020 |
| Deep Scaffolding Ltd | Construction | 2021 |
| Deep Steelworks & Architectural Ltd | Construction | 2016 |
| Deeprose Developments Limited | Construction | 2006 |
| Deevir Ltd | Real estate | 2021 |
| Defence Grade Ltd | Wholesale & retail | 2025 |
| Defence Line Ltd | Wholesale & retail | 2020 |
| Definitely Dishy Ltd | Hospitality | 2016 |
| Dehkadeh Restaurant Ltd | Hospitality | 2018 |
| DEI Building Services Ltd | Construction | 2024 |
| Deko Build Ltd | Construction | 2022 |
| Delam Care Limited | Health & social care | 1994 |
| Delanor Ltd | Manufacturing | 2012 |
| Delham Care Limited | Health & social care | 1992 |
| Delicious Catering (2000) Limited | Manufacturing | 2000 |
| DELIVER1 Ltd | Transport & logistics | 2019 |
| Delmah Trade UK Ltd | Wholesale & retail | 2021 |
| Delta Radiology Services Ltd | Health & social care | 2020 |
| Delta Services Inc Limited | Real estate | 2006 |
| Deltatel Limited | Information & communication | 1985 |
| Denham Cars Ltd | Wholesale & retail | 2019 |
| Denham Conservation Group Limited | Other services | 2026 |
| Denham Golf Club Limited | Arts & recreation | 1910 |
| Denham Optical Services Limited | Health & social care | 2007 |
| Denham Place RTM Company Limited | Households | 2025 |
| Denham PUB Company Limited | Hospitality | 2022 |
| Denham Technical Services Limited | Information & communication | 1999 |
| Denham Vehicle Detailing Limited | Other services | 2018 |
| Denham Vehicle Services Limited | Wholesale & retail | 1999 |
| Denham Waterski Club Ltd | Construction | 2023 |
| Denham.Psm Ltd | Households | 2021 |
| Denise Jacobs Limited | Information & communication | 2013 |
| Dentistry FIX Limited | Manufacturing | 2023 |
| Denvil Developments Ltd | Real estate | 2017 |
| Denyse Jones Management Ltd | Administrative & support | 2022 |
| Deol Construction Limited | Construction | 2003 |
| Derivquant Consultancy Ltd | Information & communication | 2025 |
| Dermaglow Skincare Ltd | Other services | 2025 |
| Dernier CRI London Ltd | Construction | 2019 |
| Dernier Group Limited | Real estate | 2023 |
| Dernier Holdings Ltd | Financial services | 2024 |
| Dernier Moda Ltd | Wholesale & retail | 2020 |
| Deropo Limited | Professional & scientific | 2016 |