| David Mostkow Ltd | Information & communication | 2018 |
| David Stern Opticians Limited | Health & social care | 2017 |
| David Thomas Systems Limited | Information & communication | 2010 |
| Davis HR Solutions Limited | Administrative & support | 2025 |
| Daviscom Limited | Information & communication | 2022 |
| Dawn & Dusk Beauty Limited | Wholesale & retail | 2020 |
| Day Solicitors Limited | Professional & scientific | 2009 |
| Dayley Bars Ltd | Hospitality | 2022 |
| Daytona Designs Limited | Wholesale & retail | 1996 |
| DB Golfing Limited | Arts & recreation | 2017 |
| DB Rigging Ltd | Construction | 2025 |
| DBC Decorating Ltd | Construction | 2025 |
| Dbexpert Limited | Administrative & support | 2010 |
| DBS Healthcare Design and Build Limited | Other services | 2019 |
| DBS Sound Limited | Information & communication | 2012 |
| DC Bodyworx Limited | Wholesale & retail | 2019 |
| DC Electrics Holdings Limited | Financial services | 2025 |
| DC23 Ltd | Information & communication | 2021 |
| Dcdo Medical Services Limited | Health & social care | 2014 |
| DD Healthcare Services Limited | Wholesale & retail | 2012 |
| DDB Group Services Ltd | Construction | 2025 |
| DDC Maintenance (Luton) Ltd | Manufacturing | 2015 |
| DDF Marketing Limited | Administrative & support | 2015 |
| Ddmn Limited | Health & social care | 2015 |
| Dead Dolly Limited | Extraterritorial | 2019 |
| Dead Quiet Studio Ltd | Information & communication | 2026 |
| Deans Lawn Berkhamsted Limited | Households | 1999 |
| Deans Solutions Ltd | Construction | 2026 |
| Deathcult Games Ltd | Information & communication | 2026 |
| Deavesons Jewellers Limited | Wholesale & retail | 2005 |
| Deborah Moles Limited | Information & communication | 2016 |
| Debs Buttys Ltd | Hospitality | 2023 |
| DEC Carpentry&Interiors Ltd | Construction | 2016 |
| Decade Three Associates Ltd | Professional & scientific | 2022 |
| Decentralised Energy Limited | Information & communication | 2024 |
| Decisive Management Limited | Arts & recreation | 2012 |
| Decisive Security Ltd | Energy | 2024 |
| Decosta Music Ltd | Arts & recreation | 2019 |
| Dedicated Drivers Limited | Transport & logistics | 2019 |
| Deees Kitchen Ltd | Hospitality | 2022 |
| Deejah Ltd | Health & social care | 2022 |
| Deepin Hair Ltd | Wholesale & retail | 2025 |
| DEF CON Holdings Limited | Financial services | 2018 |
| Defense.Com Cyber Ltd | Information & communication | 2024 |
| Defense.Com Holdings Ltd | Financial services | 2024 |
| Defense.Com UK Ltd | Information & communication | 2023 |
| Definitive Special Projects Limited | Arts & recreation | 1992 |
| DEL Design Ltd | Professional & scientific | 2023 |
| Delbre Ltd | Professional & scientific | 2025 |
| Delev Ltd | Hospitality | 2021 |
| Deliberate Digital Limited | Wholesale & retail | 2015 |
| Delicate Movements Limited | Transport & logistics | 2010 |
| Delight Afriquecaribbean Food Limited | Wholesale & retail | 2024 |
| Delight Investment (U.K.) Limited | Wholesale & retail | 2012 |
| Delipo Limited | Hospitality | 2024 |
| Deliverytree Ltd | Transport & logistics | 2025 |
| Delpack Household Limited | Manufacturing | 2023 |
| Delphi Care Solutions Ltd | Information & communication | 2019 |
| Delta Communications (IS) Limited | Information & communication | 2017 |
| Deluxe Living Ltd | Wholesale & retail | 2018 |
| Denestzy Limited | Wholesale & retail | 2025 |
| Denhurst Management Limited | Professional & scientific | 2003 |
| Denise Holdings UK Ltd | Construction | 2022 |
| Denova Consulting Ltd | Information & communication | 2023 |
| Dental House Property Company Limited | Health & social care | 2018 |
| Dental Laser Training Academy Ltd | Health & social care | 2016 |
| Dentalwell Ltd | Health & social care | 2025 |
| Dentax Protection Ltd | Administrative & support | 2011 |
| Dentco Limited | Health & social care | 2017 |
| Derek Gibbons Newmedia Limited | Information & communication | 2008 |
| Derivative One Ltd | Other services | 2019 |
| Derivative Two Ltd | Construction | 2019 |
| Derma Muse Ltd | Construction | 2023 |
| Dermalogix London Limited | Health & social care | 2024 |
| Derra Ltd | Transport & logistics | 2025 |
| Desh Trading Limited | Hospitality | 2016 |
| Design & Build Architects Ltd | Professional & scientific | 2020 |
| Design a View Ltd | Construction | 2025 |
| Design and Technology Services Ltd | Construction | 2009 |
| Design Team Consultants Limited | Professional & scientific | 2005 |
| Design. Consult. Construct. Collab. Ltd | Administrative & support | 2024 |
| Designer Surface Solutions Limited | Wholesale & retail | 2020 |
| Desitrans Ltd | Transport & logistics | 2017 |
| Dest Property Ltd | Real estate | 2022 |
| Destiny Support Care Limited | Health & social care | 2014 |
| Devane Ltd | Construction | 2026 |
| Devine Education Consultancy Limited | Education | 2019 |
| Devoted Home Care Services Ltd | Health & social care | 2023 |
| Devoted Supported Living Limited | Administrative & support | 2021 |
| DEZ Services Limited | Health & social care | 2022 |
| DFD Services Limited | Other services | 2005 |
| DFM Garden Services Limited | Other services | 2014 |
| DFS Construction Limited | Administrative & support | 2018 |
| Dgms Holdings Limited | Construction | 2026 |
| Dgreat Limited | Professional & scientific | 2018 |
| DGS Roofing Ltd | Construction | 2021 |
| Dgtel Consulting Limited | Professional & scientific | 2018 |
| DH Drainage Limited | Construction | 2020 |
| DH Plumbing and Heating Ltd | Construction | 2006 |
| Dhella Healthcare Ltd | Health & social care | 2025 |