| Direct Freight Systems Limited | Transport & logistics | 1994 |
| Direct Labour Group Ltd | Construction | 2019 |
| Direct Link Recruitment Ltd | Administrative & support | 2019 |
| Direct Motor Storage Limited | Transport & logistics | 2023 |
| Direct Services (UK) Ltd | Construction | 2014 |
| Direct Sofas and Beds Limited | Wholesale & retail | 2025 |
| Direct Source (UK) Limited | Wholesale & retail | 2003 |
| Direct Systems Ltd | Wholesale & retail | 2017 |
| Direct Trade Frames Ltd | Manufacturing | 2020 |
| Direct Transport Ltd | Wholesale & retail | 2020 |
| Directional Solutions Ltd | Administrative & support | 2016 |
| Directon Trade PC | | 2018 |
| Dirt Events Limited | Hospitality | 2018 |
| Dirty Dumpty Developments Limited | Households | 2026 |
| Dirty Soda Ltd | Wholesale & retail | 2024 |
| Dirtykit Limited | Administrative & support | 2020 |
| Disability Sport Wales Management Company Limited | Arts & recreation | 2009 |
| Disability Wales/Anabledd Cymru | Health & social care | 1986 |
| Disciples in Business UK Ltd | Administrative & support | 2024 |
| Disco Bar Walsall Ltd | Hospitality | 2009 |
| Disco Volante 3000 Ltd | Financial services | 2015 |
| Discount Digital Ltd | Wholesale & retail | 2019 |
| Discount Drives and Patios Ltd | Administrative & support | 2019 |
| Discount LAB Supplies Ltd | Wholesale & retail | 2016 |
| Discount Windows and Doors Ltd | Manufacturing | 2019 |
| Discountsarena Ltd | Wholesale & retail | 2024 |
| Discover E-Solutions Ltd. | Information & communication | 2001 |
| Discovery Administration Limited | Financial services | 2024 |
| Discovery Logic Limited | Information & communication | 2025 |
| Discovery Sipp Limited | Financial services | 2024 |
| Dish Forager Ltd | Information & communication | 2024 |
| Diskzone Ltd | Wholesale & retail | 2025 |
| Disli Ltd | Wholesale & retail | 2025 |
| Dislocal Limited | Wholesale & retail | 2024 |
| Disorx Ltd | Wholesale & retail | 2026 |
| Dispatch Hero Ltd | Transport & logistics | 2024 |
| Dispense Scientific Limited | Manufacturing | 2015 |
| Displaced People in Action Ltd | Other services | 2006 |
| Dispute Resolution Centre Wales Canolfan Datrys Anghydfodau Cymru Ltd | Education | 2023 |
| Disraeli House Management Company Limited | Real estate | 2013 |
| Disruptieve Ltd | Administrative & support | 2016 |
| Distinct Imaging and Events Limited | Hospitality | 2024 |
| Distinctive Purveyor Ltd | Wholesale & retail | 2015 |
| Distinguish Doors Solutions Limited | Wholesale & retail | 2016 |
| Distinguished Store Corner Trading Limited | Wholesale & retail | 2025 |
| District Kids Clothing Ltd | Wholesale & retail | 2025 |
| DISTRICT5 Ltd | Information & communication | 2016 |
| DIT DOT Dash Properties Limited | Real estate | 2026 |
| Dita Properties Ltd | Real estate | 2015 |
| Ditect Ltd | Information & communication | 2011 |
| Ditman Services Ltd | Administrative & support | 2020 |
| Ditrance Ltd | Information & communication | 2021 |
| Ditya IT Consultancy Service Ltd | Information & communication | 2017 |
| DIV Blessing Limited | Professional & scientific | 2015 |
| Diva Music Festival Limited | Arts & recreation | 2019 |
| Divacove Ltd | Wholesale & retail | 2025 |
| Divalol Ltd | Administrative & support | 2019 |
| Dive Bar Cardiff Ltd | Hospitality | 2026 |
| Divecarib Limited | Arts & recreation | 2015 |
| Divercity UK Ltd | Professional & scientific | 2021 |
| Divergent Entertainment Limited | Arts & recreation | 2018 |
| Diversa Sale PC | | 2018 |
| Diverse Construction Solutions Limited | Other services | 2017 |
| Diverse Mortgage and Protection Ltd | Financial services | 2016 |
| Diverse Welding and Fabrication Limited | Manufacturing | 2024 |
| Diverse-Paths-Consulting Ltd | Professional & scientific | 2024 |
| Diversity Network Investments Limited | Financial services | 2020 |
| Diversity Network Ltd | Real estate | 2011 |
| Diversity Solutions Limited | Public administration | 2022 |
| Divert TV Ltd | Information & communication | 2020 |
| Dividing Management Services Limited | Real estate | 2023 |
| Divine Car Hire Limited | Administrative & support | 2019 |
| Divine Cars Limited | Administrative & support | 2018 |
| Divine Caterers Ltd | Hospitality | 2018 |
| Divine Couriers Ltd | Transport & logistics | 2025 |
| Divine Emok Foods Limited | Wholesale & retail | 2026 |
| Divine Encounter Worship Ministry Ltd | Other services | 2024 |
| Divine Favour Enterprises Ltd | Health & social care | 2008 |
| Divine Hadicrafts UK Ltd | Wholesale & retail | 2026 |
| Divine Protection Ltd | Administrative & support | 2017 |
| Divitiae Pecunia Limited | Construction | 2023 |
| Divorce Club Ltd | Administrative & support | 2016 |
| Diwan Trading Company Ltd | Wholesale & retail | 2020 |
| Diwhy Ltd | Construction | 2019 |
| Dixon & Stone Limited | Professional & scientific | 2008 |
| Dixon Economics Limited | Professional & scientific | 2016 |
| Dixon Investments Limited | Real estate | 2019 |
| Dixon Language Services Limited | Professional & scientific | 2024 |
| Dixon's Delight Catering Ltd | Hospitality | 2024 |
| Dixons Direct Limited | Wholesale & retail | 2025 |
| Dixos Analytics Limited | Information & communication | 2020 |
| Dixsons Properties (Cardiff) Limited | Real estate | 1996 |
| Dixy-It Limited | Construction | 2020 |
| Dizayee Bros Ltd | Wholesale & retail | 2025 |
| Dizzer Limited | Information & communication | 2024 |
| Dizzy Banjo Ltd | Information & communication | 2014 |
| DJ Decorations & Building Services Limited | Construction | 2015 |
| DJ Hill Engineering Services Limited | Manufacturing | 2009 |
| DJ Miller Plumbing Limited | Construction | 2019 |
| DJ Miller Property Limited | Real estate | 2020 |