| Ullahs Legacy Empire Ltd | Wholesale & retail | 2025 |
| Ultimate Window Systems Holdings Limited | Financial services | 2021 |
| Ultimate Window Systems Limited | Construction | 2001 |
| Uniserve Wales Fire Protection Ltd | Public administration | 2021 |
| Universal Chassis Limited | Professional & scientific | 2020 |
| Universal Glamping Pods Ltd | Wholesale & retail | 2017 |
| Urban Tapestry Software Ltd | Information & communication | 2019 |
| V Best Partner Limited | Hospitality | 2016 |
| V.B. Patel Limited | Professional & scientific | 2024 |
| Valley Auto Sport Ltd | Wholesale & retail | 2025 |
| Valley Motor (Services) Limited | Wholesale & retail | 2014 |
| Vampire Supplies Ltd | Wholesale & retail | 2025 |
| Vape Shop Ammanford Ltd | Wholesale & retail | 2025 |
| VAT431 Reclaims by Andrew Jones Ltd | Professional & scientific | 2024 |
| Vcsm Properties Limited | Real estate | 2025 |
| Vehicle Glazing Specialists Ltd | Wholesale & retail | 2014 |
| Velran Properties Limited | Real estate | 2018 |
| Verdi Adifi Solutions Ltd | Professional & scientific | 2025 |
| Victoria Filling Station (MH) Limited | Wholesale & retail | 2023 |
| Victoria John Homes Ltd | Real estate | 2013 |
| Victoria John of London Ltd | Manufacturing | 2014 |
| Victoria John Wales Ltd | Other services | 2018 |
| Victorian House (Sales) Ltd | Manufacturing | 2010 |
| Victorian House Window Group Ltd | Financial services | 2010 |
| Vision Tech AV Ltd | Information & communication | 2024 |
| Volrok Ltd | Information & communication | 2026 |
| Vonyq Ltd | Wholesale & retail | 2024 |
| VST Hire Service Limited | Administrative & support | 2018 |
| W D Seward & Sons Limited | Other services | 2026 |
| W3 Properties Limited | Real estate | 2020 |
| Waffle Lads Limited | Hospitality | 2026 |
| Wales Beckons Ltd | Administrative & support | 2015 |
| Walkover Sprayers Ltd | Manufacturing | 2019 |
| Wall to Wall Building Services Ltd | Construction | 2009 |
| Wanderlust Welsh Ltd | Information & communication | 2021 |
| Warrendale Construction Limited | Construction | 2005 |
| Water for YOU Limited | Hospitality | 2005 |
| Watkins Commercial Vehicle Repairs Ltd | Wholesale & retail | 2026 |
| Watkins Timber Buildings Limited | Manufacturing | 2002 |
| Waylander Property Limited | Real estate | 2021 |
| Web Accounts Ltd | Professional & scientific | 2013 |
| Wedge Electrical Ltd | Construction | 2019 |
| Welding Repairs (Brynaman) Limited | Manufacturing | 2002 |
| Welsh Scoop Ltd | Manufacturing | 2026 |
| West END Cafe Limited | Hospitality | 2002 |
| West END Cuts Limited | Other services | 2014 |
| West Wales Development Trust | Construction | 2010 |
| West Wales Developments Limited | Construction | 2004 |
| West Wales MOT Services Limited | Wholesale & retail | 2018 |
| West Wales Tourers Ltd | Wholesale & retail | 2021 |
| Wetdan Developments Limited | Construction | 2002 |
| Where for Art NOW? Ltd | Professional & scientific | 2017 |
| White Buffalo Eco-Design Limited | Extraterritorial | 2007 |
| Wifi 4 Wales Limited | Information & communication | 2024 |
| Wild Bluebell Limited | Education | 2006 |
| Wildwoods Arboriculture Wales Ltd | Agriculture & fishing | 2022 |
| Will Plumbing Ltd | Construction | 2025 |
| Williams Consultancy Limited | Professional & scientific | 1998 |
| Williams Housing and Trading Ltd | Financial services | 2024 |
| Wing&Prayer Ltd | Hospitality | 2025 |
| Wonky Signs Ltd | Professional & scientific | 2024 |
| Woodall & James Carpentry & Building Limited | Construction | 2024 |
| Worrall Crossing Property Limited | Real estate | 2022 |
| WR Jones (Ammanford) Ltd | Construction | 2025 |
| Wright Support Services Limited | Transport & logistics | 2014 |
| Wright Ways Contractors Ltd | Construction | 2019 |
| WRK Scaffolding Limited | Construction | 2016 |
| WSA Electrical Contracting Ltd | Manufacturing | 2022 |
| Y Banc Limited | Hospitality | 2023 |
| Y Cwtsh Limited | Hospitality | 2013 |
| Y Pantri Glas CYF | Wholesale & retail | 2019 |
| Yantomech Limited | Professional & scientific | 2018 |
| Ymasiad CYF | Hospitality | 2025 |
| York Falcons Limited | Agriculture & fishing | 2023 |
| YR Haden C.I.C. | Hospitality | 2026 |
| YR HEN Ysgol Ltd | Hospitality | 2019 |
| Ysguborwen Ltd | Hospitality | 2021 |
| Yummies Pizza Ltd | Hospitality | 2022 |
| Zenflora Ltd | Wholesale & retail | 2011 |
| ZOO Brew Limited | Manufacturing | 2002 |
| Zyvo Limited | Transport & logistics | 2025 |