| Webfitwales Ltd | Other services | 2013 |
| Ween Ltd | Administrative & support | 2024 |
| Well Well Limited | Education | 2019 |
| Wellnessvault (Port Talbot) Limited | Arts & recreation | 2026 |
| Welsh Coastal Staycations Ltd | Real estate | 2024 |
| Welshy's Exterior Cleaning Ltd | Administrative & support | 2025 |
| Welspeed Engineering Limited | Construction | 2018 |
| WES Rees Commercial Properties Limited | Real estate | 2022 |
| West Coast Plastics Ltd | Construction | 2019 |
| West Pest Solutions Ltd | Administrative & support | 2025 |
| West Wales Bacon Supplies Limited | Wholesale & retail | 2014 |
| West Wales Fire Sprinklers Ltd | Construction | 2025 |
| West Wales General Surgery Limited | Health & social care | 2016 |
| West Wales Plant Limited | Wholesale & retail | 2018 |
| West Wales Trade Sales Limited | Wholesale & retail | 2014 |
| Westfa Garage Limited | Wholesale & retail | 2025 |
| Weston Paintworx Ltd | Wholesale & retail | 2025 |
| Westworld Leisure Ltd | Administrative & support | 2016 |
| Wgarchitects Ltd | Professional & scientific | 2023 |
| Whatley Homes Ltd | Real estate | 2026 |
| Whaymans Enterprises Limited | Hospitality | 2025 |
| Whaymans Events Limited | Hospitality | 2023 |
| White Lion Felinfoel Ltd | Hospitality | 2020 |
| White Lion Garage Ltd | Wholesale & retail | 2026 |
| White`S Garage Limited | Wholesale & retail | 2002 |
| Whitford Commercial Properties Ltd | Real estate | 2025 |
| Whitford Properties Limited | Real estate | 2021 |
| Whitworth Engineering Services Ltd | Administrative & support | 2021 |
| Wildecraft CYF | Health & social care | 2020 |
| William & Irene Limited | Manufacturing | 2020 |
| Williams Electrical Contractors (Cymru) Ltd | Construction | 2015 |
| Williams Marine Limited | Agriculture & fishing | 2017 |
| Williams Property Collection Limited | Real estate | 2025 |
| Williams Solar Clean Ltd | Administrative & support | 2024 |
| Williams Solar Ltd | Construction | 2023 |
| Wins Sports CIC | Arts & recreation | 2024 |
| Wins Sports Holding Ltd | Real estate | 2024 |
| Winser Property & Investments Ltd | Real estate | 2020 |
| Wiring by Williams Ltd | Construction | 2024 |
| Witchcraft Aesthetics and Permanent Make-Up Limited | Other services | 2024 |
| Wkkitesurfproject Ltd | Education | 2017 |
| WKO Ltd | Education | 2020 |
| Wolfie Foods Ltd | Hospitality | 2023 |
| Workers Nest Ltd | Hospitality | 2025 |
| World Horizons Limited | Other services | 1982 |
| World Sport Broadcasting Limited | Information & communication | 1979 |
| World Sport Television Limited | Information & communication | 1982 |
| Worldwide Analyteeqs Limited | Wholesale & retail | 2025 |
| Worldwide Entertainment News Limited | Information & communication | 1992 |
| WPX Estates Ltd | Real estate | 2025 |
| Wyatt & Watts Limited | Professional & scientific | 2012 |
| WYN Bishop Ltd | Other services | 2013 |
| WYN Hughes Limited | Mining & quarrying | 2012 |
| X Best Times Limited | | 2015 |
| Xenon Films Limited | Information & communication | 2024 |
| Xfitl Limited | Arts & recreation | 2017 |
| Xstate Limited | Real estate | 2026 |
| Y Ddraenen WEN CIC | Arts & recreation | 2026 |
| Y Geulan Management Company Limited | Households | 2023 |
| Y Levens Ltd | Manufacturing | 2025 |
| Y Pantri Bach CYF | Wholesale & retail | 2018 |
| Y TŶ Celf - the Art House Ltd CIC | Education | 2017 |
| Yandi Group Limited | Manufacturing | 2015 |
| Yellow Sourcing Ltd | Wholesale & retail | 2022 |
| Ymlaen Limited | Construction | 2014 |
| Ymlaen Llanelli Limited | Administrative & support | 2016 |
| Yoobik Limited | Information & communication | 2011 |
| Yorkshire Dales Spa Limited | Other services | 2015 |
| Your Dentist Crosshands Ltd | Health & social care | 2024 |
| Your Money Clinic Ltd | Financial services | 2024 |
| Your Neighbourhood Property Services Ltd | Construction | 2024 |
| Yusof Takeaway Limited | Hospitality | 2025 |
| Z1C Ltd | Real estate | 2026 |
| Z1R Limited | Real estate | 2019 |
| Z2R Ltd | Real estate | 2025 |
| Zabka Mini Market Ltd | Hospitality | 2019 |
| Zealand IT Ltd | Information & communication | 2009 |
| ZEN 23 Ltd | Information & communication | 2024 |
| Zenergy Solutions Ltd | Other services | 2025 |
| Zero Alpha Fitness Ltd | Arts & recreation | 2024 |
| Zion Bliss Ltd | Hospitality | 2023 |
| Zone Broadband Ltd | Information & communication | 2023 |
| Zorin Tools Ltd | Wholesale & retail | 2026 |
| Zuri Baobab Limited | Manufacturing | 2026 |
| Zyler Projects Ltd | Real estate | 2025 |
| Zyora Hydration Limited | Wholesale & retail | 2026 |