| Damian Dunn GAS & Heating Services Limited | Construction | 2016 |
| Damp Detectors Ltd | Construction | 2025 |
| Damp Proof Specialist Ltd | Construction | 2024 |
| DAN Kidd Electrical Ltd | Administrative & support | 2017 |
| Dana Family Limited | Health & social care | 2014 |
| Daniel Handley Limited | Information & communication | 2019 |
| Daniel J Transport Services Ltd | Transport & logistics | 2014 |
| Daniel Jones Fire and Security Solutions Ltd | Construction | 2021 |
| Daniel Merritt Consulting Ltd | Information & communication | 2026 |
| Daniel Scorey Carpentry Limited | Construction | 2014 |
| Danmar Mechanical Limited | Construction | 2020 |
| Danmar Services Ltd | Financial services | 2025 |
| Dare & Hier Media Ltd | Professional & scientific | 2016 |
| Dark Spirit Studio Limited | Arts & recreation | 2024 |
| Dark Swan Ltd | Professional & scientific | 2018 |
| Darnton Technology Solutions Ltd | Manufacturing | 2024 |
| Darren Clay Groundworks Ltd | Construction | 2015 |
| Darren James BYE Limited | Other services | 2014 |
| Darussalam Publisher and Distributor Limited | Wholesale & retail | 2021 |
| Darwin Training Solutions Ltd | Education | 2024 |
| Data Line Electrical Limited | Construction | 2002 |
| Data Saves Lives Ltd | Wholesale & retail | 2024 |
| Data Views Consultancy Limited | Information & communication | 2017 |
| Datro Consortium Limited | Information & communication | 2021 |
| Davan Services Limited | Transport & logistics | 2009 |
| Dave Parratt Holdings Limited | Financial services | 2008 |
| Dave West Projects Ltd | Professional & scientific | 2019 |
| Dave Willie & Associates Limited | Other services | 2010 |
| Davenport Mechanical Ltd | Construction | 2023 |
| Daveyyyy Brand Ltd | Information & communication | 2025 |
| David Cole and Associates Limited | Professional & scientific | 2018 |
| David Grace Accountancy Limited | Professional & scientific | 2016 |
| David J Sheldon Limited | Professional & scientific | 2022 |
| David Jeffrey GAS Services Ltd | Construction | 2007 |
| David Miller Welding 2025 Limited | Construction | 2025 |
| David Newnham Building & Surfacing Ltd | Construction | 2016 |
| David Salisbury Investments Limited | Construction | 1974 |
| David Slee Rail Ltd | Professional & scientific | 2016 |
| Davies Dent Medical Limited | Health & social care | 2013 |
| Davis Ayling Media Limited | Professional & scientific | 2014 |
| Daviz Cartoons Limited | Arts & recreation | 2005 |
| Daylight Innovation Investment Support Corporation Limited | Professional & scientific | 2009 |
| Days OUT With ME Limited | Professional & scientific | 2020 |
| DB Auto Group Ltd | Wholesale & retail | 2026 |
| DB Skin Clinic Ltd | Other services | 2018 |
| DBS Building Services Nationwide Ltd | Construction | 2023 |
| DC Mathew Ltd | Transport & logistics | 2026 |
| DC Models UK Ltd | Wholesale & retail | 2020 |
| Dcato Ltd | Hospitality | 2024 |
| Dccs Cleaning Solutions Limited | Administrative & support | 2024 |
| Dccs Commercial Cleaning Solutions Ltd | Administrative & support | 2025 |
| DCD & Sons Ltd | Wholesale & retail | 2023 |
| DCG Couriers Ltd | Transport & logistics | 2025 |
| DCL Cladding Ltd | Construction | 2019 |
| DCR Systems Limited | Manufacturing | 2016 |
| DD Engineering Management Limited | Professional & scientific | 2020 |
| DDB Business Consulting UK Limited | Administrative & support | 2025 |
| DDH Electrical Services Limited | Extraterritorial | 2024 |
| DDS Lifts Ltd | Construction | 2024 |
| DE Mellow & Co Ltd | Professional & scientific | 2023 |
| Dean's Decorating Ltd | Construction | 2024 |
| Dear Associates Limited | Professional & scientific | 2004 |
| Debama Consulting Firm Limited | Professional & scientific | 2024 |
| Debney Lodge RTM Company Limited | Households | 2021 |
| Deception Films Ltd | Information & communication | 2021 |
| Decima Ltd | Manufacturing | 2024 |
| Decisions@Risk Limited | Professional & scientific | 2012 |
| Deco Eclectic Ltd | Wholesale & retail | 2019 |
| DEE Smith Limited | Health & social care | 2019 |
| Deebrickwork (UK) Ltd | Construction | 2019 |
| Deep Coast Software Limited | Information & communication | 2024 |
| Deepreel Limited | Information & communication | 2020 |
| Deesand Holdings Limited | Construction | 2010 |
| Deesand Limited | Construction | 1981 |
| Definition Systems Management Limited | Hospitality | 2002 |
| Defy Training Limited | Professional & scientific | 2012 |
| Dekali Limited | Real estate | 2012 |
| Delegate.Email Limited | Information & communication | 2025 |
| Delegated Authority Advisory Ltd | Financial services | 2019 |
| Della Dynamics Limited | Wholesale & retail | 1996 |
| Delmar Technologies Limited | Professional & scientific | 2022 |
| Delmark Group Ltd | Administrative & support | 2026 |
| Delo-Kuts Ltd | Other services | 2026 |
| Delta Jointing Services Ltd | Construction | 2025 |
| Delta Project Solutions Ltd | Professional & scientific | 2020 |
| Deltair Limited | Extraterritorial | 2015 |
| Deltamark Group Ltd | Administrative & support | 2026 |
| Deltec Holdings Limited | Professional & scientific | 2000 |
| Deltspower Assist Ltd | Transport & logistics | 2025 |
| Deltspower Limited | Health & social care | 2019 |
| Demac Catering Limited | Hospitality | 2024 |
| Denby Homes Ltd | Real estate | 2021 |
| Deneska Limited | Professional & scientific | 2015 |
| Denmead Carpentry Ltd | Construction | 2015 |
| Denmead Day Care Limited | Health & social care | 2014 |
| Denmead Mill Close Residents Ltd | Administrative & support | 2018 |
| Denmead PUB Company Limited | Hospitality | 2011 |
| Denmead Tool and Garden Hire Ltd | Administrative & support | 2023 |
| Denners Tack Shop UK Ltd | Wholesale & retail | 2012 |
| Dennison Doors Limited | Manufacturing | 2009 |