| Dhee’S Place Limited | Wholesale & retail | 2025 |
| Dhellyna Ltd | Manufacturing | 2022 |
| DHK Property Services Ltd | Real estate | 2021 |
| Dhos Holding Limited | Financial services | 2018 |
| Dhwani Academy Limited | Administrative & support | 2026 |
| DI Luccia & Partners Ltd | Administrative & support | 2024 |
| Diabeasy AS 123 Limited | Health & social care | 2015 |
| Diacon Medical Ltd | Health & social care | 2019 |
| Dialectable Limited | Wholesale & retail | 2015 |
| Dialled in Agency Ltd | Professional & scientific | 2023 |
| Diamantis Ltd | Professional & scientific | 2003 |
| Diamond Asset Management Limited | Transport & logistics | 2016 |
| Diamond Banquet Limited | Hospitality | 2022 |
| Diamond Design Services Ltd | Professional & scientific | 2018 |
| Diamond Engineering Group Ltd | Financial services | 2021 |
| Diamond Engineering Services Ltd | Manufacturing | 2009 |
| Diamond Facilities Management Limited | Administrative & support | 2020 |
| Diamond Green Aspect Ltd | Professional & scientific | 2021 |
| Diamond Lettings Yorkshire Limited | Real estate | 2023 |
| Diamond Luxe Property Services Ltd | Households | 2025 |
| Diamond Market Ltd | Wholesale & retail | 2026 |
| Diamond P & G Consultancy Limited | Administrative & support | 2023 |
| Diamond Paws (Barnsley) Ltd | Other services | 2021 |
| Diamond Rail Group Limited | Manufacturing | 2017 |
| Diamond Rail Services (UK) Limited | Manufacturing | 2010 |
| Diamond Responsive Engineering Ltd | Manufacturing | 2006 |
| Diamond Responsive Group Ltd | Financial services | 2016 |
| Diamond Union Ltd | Real estate | 2022 |
| Diamond Wedding Services Ltd | Administrative & support | 2025 |
| Diamonddluxewears Ltd | Wholesale & retail | 2026 |
| Diamonds Estate Ltd | Real estate | 2025 |
| Diana's Collections Ltd | Wholesale & retail | 2018 |
| Diane Milnes Ltd. | Other services | 2015 |
| Diatom Watches Ltd | Manufacturing | 2023 |
| Dibco Tools Limited | Administrative & support | 2021 |
| Dibrian Ltd | Health & social care | 2011 |
| Dibujo.Design Interiors Ltd | Professional & scientific | 2022 |
| Dickens Consulting Ltd | Professional & scientific | 2001 |
| Dickinson Farm Services Ltd | Extraterritorial | 2025 |
| Dickinson Property Management Limited | Real estate | 2005 |
| Dickinson Trading Ltd | Manufacturing | 2020 |
| Dickory Dock Nursery | Education | 2003 |
| Dictionary of Classical Hebrew Limited | Information & communication | 2000 |
| Didier Freund Limited | Professional & scientific | 2019 |
| Didsbury Social Ltd | Hospitality | 2026 |
| Diemet UK Limited | Other services | 2023 |
| Diespeker (GRP) Limited | Manufacturing | 2021 |
| Diet of Worms Limited | Hospitality | 2015 |
| Diet Plan Unique Ltd | Wholesale & retail | 2015 |
| Dietlenz Ltd | Information & communication | 2026 |
| Diff Ltd | Information & communication | 2019 |
| Differ Electrical Services Limited | Construction | 2024 |
| Different World Travel Limited | Administrative & support | 1997 |
| Differentis Advisory Ltd | Information & communication | 2021 |
| Differentis Ltd | Information & communication | 2000 |
| Difr Ltd. | Arts & recreation | 2015 |
| Difr Properties Limited | Real estate | 2019 |
| Difuria Training & Plant Limited | Administrative & support | 2013 |
| DIG Deep (Africa) | Health & social care | 2012 |
| DIG Deep Challenges Limited | Other services | 2013 |
| DIG Deeper Ltd | Wholesale & retail | 2018 |
| DIG Properties Limited | Real estate | 2017 |
| DIG Where YOU Stand C.I.C. | Education | 2024 |
| Digby Property Ltd | Real estate | 2026 |
| Digger Crush Ltd | Water & waste | 2023 |
| Diggi Energies Limited | Construction | 2024 |
| Digglers.Com Ltd | Hospitality | 2024 |
| Digi Brainiacs Ltd | Professional & scientific | 2025 |
| Digi Depot Ltd | Wholesale & retail | 2025 |
| DIGIB3X Ltd | Information & communication | 2018 |
| Digibooks Ltd | Information & communication | 2016 |
| Digihub Solutions Limited | Professional & scientific | 2025 |
| Digilegal Group Limited | Financial services | 2025 |
| Digilegal Holdings Ltd | Information & communication | 2008 |
| Digilegal Limited | Information & communication | 2011 |
| Digilegal Trustees Limited | Professional & scientific | 2020 |
| Digiquest Consulting Limited | Information & communication | 2024 |
| Digital Art Department Limited | Professional & scientific | 2016 |
| Digital Autopsy Technologies Ltd | Information & communication | 2024 |
| Digital Colour Limited | Information & communication | 2014 |
| Digital Exchange Limited | Information & communication | 1995 |
| Digital Framework Ltd | Information & communication | 2010 |
| Digital Goat Limited | Information & communication | 2020 |
| Digital Impact Solutions Ltd | Other services | 2015 |
| Digital Micrometers Ltd | Manufacturing | 2009 |
| Digital Orchid Graphics Limited | Arts & recreation | 2013 |
| Digital Park Property Limited | Real estate | 2021 |
| Digital Physical Technology Holdings Ltd | Information & communication | 2026 |
| Digital Processes Limited | Information & communication | 2004 |
| Digital Property Risk Limited | Information & communication | 2022 |
| Digital Solutions Global Ltd | Professional & scientific | 2020 |
| Digital Track Ltd | Wholesale & retail | 2025 |
| Digitalcrumbz Ltd | Professional & scientific | 2013 |
| Digitalpharm Ltd | Professional & scientific | 2018 |
| Digitalphysical Ltd | Information & communication | 2025 |
| Digitalsonic Limited | Administrative & support | 1999 |
| Dignity Support Services Limited | Wholesale & retail | 2014 |
| Dikes Limited | Construction | 2021 |
| DIL AY Ltd | Health & social care | 2014 |
| DIL89 Limited | Real estate | 2025 |