| Dover Place Ltd | Real estate | 2019 |
| Dovetail Properties Ltd | Real estate | 2024 |
| DOW Advisory Limited | Professional & scientific | 2019 |
| Down DE Road Records Limited | Information & communication | 2009 |
| Downend Aggregates and Restoration Limited | Extraterritorial | 2009 |
| DP Blade Services Ltd | Manufacturing | 2024 |
| DP Financial Marketing Limited | Financial services | 2004 |
| DP Medical Services Limited | Health & social care | 2015 |
| DPC Consultancy Ltd | Professional & scientific | 2011 |
| DPW Associates Ltd | Professional & scientific | 2022 |
| Dpwaste Limited | Water & waste | 2026 |
| DR Alison White & Partners LLP | | 2014 |
| DR C Wilson Limited | Administrative & support | 2010 |
| DR Chris Wright Consulting Ltd | Professional & scientific | 2022 |
| DR Composites Ltd | Manufacturing | 2025 |
| DR Deliveries Ltd | Transport & logistics | 2025 |
| DR Dilum Jayawickrama Medicolegal Services Limited | Health & social care | 2024 |
| DR Jane Clark Engineering Science Ltd | Professional & scientific | 2025 |
| DR JO Aesthetics Limited | Professional & scientific | 2015 |
| DR Lilli Limited | Health & social care | 2018 |
| DR Mohamed Al-Kadoshi Ltd | Wholesale & retail | 2026 |
| DR Natasha Collins Healthcare Ltd | Health & social care | 2026 |
| DR R Ahmed Limited | Health & social care | 2022 |
| DR R Khaffaf Limited | Health & social care | 2020 |
| DR Rhys Jones Limited | Professional & scientific | 2012 |
| Dr.Knit Ltd | Households | 2025 |
| Drac Access Solutions Ltd | Construction | 2022 |
| Draconis Cards Limited | Wholesale & retail | 2025 |
| Draethen Electromech Ltd | Construction | 2023 |
| Draethen Group Ltd | Financial services | 2020 |
| Draethen Process Control Ltd | Construction | 2020 |
| Draethen Solutions Ltd | Professional & scientific | 2014 |
| Draft Haven Limited | Administrative & support | 1989 |
| Dragon Car Wash Cwmbran Limited | Other services | 2022 |
| Dragon Cleaning Limited | Administrative & support | 2025 |
| Dragon Consulting Services Limited | Professional & scientific | 2019 |
| Dragon D3SIGNS Co Ltd | Wholesale & retail | 2025 |
| Dragon Dispatch Limited | Transport & logistics | 2024 |
| Dragon Electrical Services Limited | Wholesale & retail | 1994 |
| Dragon Financial Planning Ltd | Financial services | 2019 |
| Dragon FPL Holding Co Limited | Financial services | 2024 |
| Dragon Furniture Limited | Wholesale & retail | 2010 |
| Dragon Heating & Cooling Ltd | Construction | 2026 |
| Dragon Heating & Plumbing Ltd | Construction | 2020 |
| Dragon Perks (Rewards) Ltd | Administrative & support | 2022 |
| Dragon Plumbing & Heating Ltd | Construction | 2015 |
| Dragon Scaffolding Limited | Construction | 2017 |
| Dragon Soul Custom UK Ltd | Wholesale & retail | 2021 |
| Dragon Soul Projects Limited | Manufacturing | 2023 |
| Dragon Tuning Ltd | Professional & scientific | 2016 |
| Dragon View Consulting Ltd | Professional & scientific | 2014 |
| Dragon Water Technologies Limited | Water & waste | 2018 |
| Dragon Windows Upvc Limited | Manufacturing | 2021 |
| Dragon's Gate IOW Ltd | Hospitality | 2025 |
| Dragonfly Emporium Limited | Wholesale & retail | 2003 |
| Dragonfly Technology Solutions Ltd | Information & communication | 2018 |
| Dragonland Consulting Limited | Information & communication | 2004 |
| Dragons of Newport Business Club Ltd | Administrative & support | 2025 |
| Dragons RFC Limited | Arts & recreation | 2017 |
| Dragons Rugby Limited | Arts & recreation | 2017 |
| Dragons Stadium Limited | Arts & recreation | 2017 |
| Draig Rail Ltd | Construction | 2022 |
| Drainrod Limited | Water & waste | 1977 |
| Dream Art Decor Ltd | Information & communication | 2014 |
| Dream Building Services Ltd | Construction | 2016 |
| Dream Knowledge Ltd | Information & communication | 2023 |
| Dream Team Interior Ltd | Construction | 2017 |
| Dreaming in Fire Limited | Arts & recreation | 2010 |
| Dreams and Wishes | Other services | 2011 |
| Dreams Care Homes ( Danygraig) Limited | Health & social care | 2013 |
| Dreams Care Homes (TY Coch) Limited | Health & social care | 2024 |
| Dreams Holdings (RB) Limited | Health & social care | 2021 |
| Drews Scaffolding South Wales Ltd | Construction | 2018 |
| DRF Holdings Limited | Information & communication | 2023 |
| Driscoll Young Limited | Professional & scientific | 2012 |
| Drivers 4 Europe Ltd | Transport & logistics | 2026 |
| Drivesecure Services Limited | Administrative & support | 2025 |
| Driveway Defence Ltd | Administrative & support | 2025 |
| DRIVEWAY4YOU Ltd | Construction | 2025 |
| Dropgo Ltd | Wholesale & retail | 2022 |
| Dropout Enterprises Ltd | Wholesale & retail | 2026 |
| Drsheatingservices Ltd | Construction | 2025 |
| Drumlanrig Bar - Jock Reids Ltd | Hospitality | 2021 |
| Drumlord Limited | Manufacturing | 1981 |
| DRV Trans Ltd | Transport & logistics | 2018 |
| DRY River Limited | Real estate | 2004 |
| Drytone Ltd | Manufacturing | 2025 |
| DS Autobody and Recovery Services Ltd | Wholesale & retail | 2026 |
| DS Carpet Cleaning Services Ltd | Administrative & support | 2021 |
| DS Composites Ltd | Manufacturing | 2025 |
| DS Paint and Body Restorers Ltd | Wholesale & retail | 2024 |
| DSD Property Services Ltd | Construction | 2019 |
| DSH Copywriters Ltd | Information & communication | 2023 |
| DSJ Bubbles Ltd | Construction | 2020 |
| DSS Foods Limited | Hospitality | 2025 |
| DT Site Management Services Ltd | Administrative & support | 2024 |
| Dtcw Ltd | Wholesale & retail | 2024 |
| DTJ Fabrication & Welding Ltd | Manufacturing | 2026 |
| DTM Psychology Services Limited | Health & social care | 2025 |
| DTP Innovations Limited | Information & communication | 2025 |