| Wiltshire Scrapstore and Resource Centre Limited | Arts & recreation | 1999 |
| Wiltshire Senior Football League Limited | Arts & recreation | 2021 |
| Wiltshire Slip and Slide Limited | Arts & recreation | 2025 |
| Wiltshire Smart Repairs Ltd | Wholesale & retail | 2026 |
| Wiltshire Stonemasons Ltd | Manufacturing | 2020 |
| Wiltshire Surveyors Ltd | Households | 2023 |
| Wiltshire Timber Supplies Ltd | Wholesale & retail | 2022 |
| Wiltshire Tool Hire Ltd. | Administrative & support | 2014 |
| Wiltshire Vision Ltd | Professional & scientific | 2026 |
| Wiltshire Wood Recycling Community Interest Company | Water & waste | 2005 |
| Wiltshiredining Ltd | Hospitality | 2025 |
| Wiltshirevenezia Ltd | Hospitality | 2026 |
| Wilvan Interior Design&Installation Ltd | Wholesale & retail | 2016 |
| Wincanton A&R Limited | Information & communication | 2023 |
| Wincanton Air & Ocean Limited | Extraterritorial | 1960 |
| Wincanton Group Limited | Extraterritorial | 1947 |
| Wincanton High Tech Limited | Professional & scientific | 1980 |
| Wincanton Holdings Limited | Financial services | 1987 |
| Wincanton Limited | Transport & logistics | 2001 |
| Wincanton Logistics Limited | Extraterritorial | 1972 |
| Wincanton Pension Scheme Trustees Limited | Extraterritorial | 2001 |
| Wincanton Techco Limited | Financial services | 2023 |
| Wincanton Trans European Limited | Financial services | 1936 |
| Windhager UK Limited | Wholesale & retail | 2007 |
| Windowpayne Limited | Administrative & support | 2016 |
| Windward Strategic Limited | Professional & scientific | 2004 |
| Wine Monkey Limited | Wholesale & retail | 2022 |
| Wing Forward Investment Limited | Real estate | 2025 |
| Winterwell Farm Limited | Agriculture & fishing | 2012 |
| Winterwell Ltd | Agriculture & fishing | 2022 |
| Wisteriahouse Limited | Hospitality | 2020 |
| With Pleasure Ltd | Wholesale & retail | 2024 |
| Withai Ltd | Professional & scientific | 2025 |
| Withyfield Management Consulting Ltd | Professional & scientific | 2023 |
| Witney Cable Installations Limited | Construction | 2024 |
| Wizard Rockets Limited | Wholesale & retail | 2023 |
| WKW Associates Ltd | Information & communication | 2021 |
| Wlm.Digital Ltd | Information & communication | 2010 |
| Wolfhall Sporting Limited | Agriculture & fishing | 2016 |
| Women's Time Counselling Ltd | Health & social care | 2020 |
| Wood Street Psychotherapy Limited | Administrative & support | 2024 |
| Woodbarn Enterprises Limited | Agriculture & fishing | 2025 |
| Woodlands Park Management Company Limited | Households | 1987 |
| Woodman Elite Ladies Kickboxing Ltd | Arts & recreation | 2024 |
| Woods Business Services Limited | Administrative & support | 2007 |
| Woods Consolidated Limited | Professional & scientific | 2013 |
| Woods Response Services Limited | Administrative & support | 2005 |
| Woolmore Ltd | Professional & scientific | 2003 |
| Word of Mouth Marketing Services Limited | Professional & scientific | 2003 |
| Work Insight Limited | Professional & scientific | 2014 |
| Worlocks Ltd | Information & communication | 2018 |
| Worwell Rise Management Company Limited | Households | 2025 |
| WP Fencing Limited | Administrative & support | 2007 |
| Wrightheart 1 Limited | Health & social care | 2016 |
| Write Lines Creative Limited | Professional & scientific | 2018 |
| WS Swift (Holdings) Limited | Financial services | 2024 |
| WS Swift Group Limited | Financial services | 2025 |
| WSH Estates Ltd | Real estate | 2024 |
| WSL Precast Limited | Construction | 2023 |
| Wsswift Limited | Construction | 2018 |
| Wyatt and Sons Fencing Limited | Construction | 1989 |
| Wyddfa Properties Ltd | Real estate | 2025 |
| Wynfix Ltd | Wholesale & retail | 2024 |
| Wynlet Ltd | Real estate | 2022 |
| Wynne Systems (UK) Limited | Information & communication | 2015 |
| Wyntel Ltd | Wholesale & retail | 2019 |
| Wyvern Surveyors Limited | Professional & scientific | 2021 |
| WZG Ltd | Professional & scientific | 2022 |
| X-Tra Space Bristol Limited | Transport & logistics | 2012 |
| X10 Limited | Information & communication | 2015 |
| Xanalys Ltd | Information & communication | 2008 |
| Xavier Banks Building Contractors Limited | Construction | 2023 |
| Xeniapure Ltd | Administrative & support | 2024 |
| Xform Studio Ltd | Professional & scientific | 2023 |
| XM Insights Ltd | Professional & scientific | 2023 |
| Xoqp Ltd | Information & communication | 2018 |
| Yansons Ltd | Information & communication | 2007 |
| Yates Carpentry Limited | Construction | 2009 |
| Yatton Keynell Village Store Limited | Wholesale & retail | 2002 |
| Yell Cabs Taxis Ltd | Transport & logistics | 2009 |
| Yellow Holdco Limited | Professional & scientific | 2026 |
| Yellow Jersey Consultancy Limited | Professional & scientific | 2023 |
| Yellow Keys Properties Limited | Real estate | 2025 |
| Yellow Wages Limited | Other services | 2015 |
| YEW Tree Farm Limited | Agriculture & fishing | 1992 |
| YG Homes Ltd | Real estate | 2023 |
| Yilmaz Take Away Limited | Hospitality | 2022 |
| Yorkshire Marquee Company Limited | Administrative & support | 2024 |
| Young Skin Ltd | Wholesale & retail | 2024 |
| Your Finance Department Ltd | Professional & scientific | 2024 |
| Your Home and Property Limited | Professional & scientific | 2011 |
| Your Mortgage Consultants Limited | Financial services | 2022 |
| Your TAE Kwon-Do Limited | Arts & recreation | 2013 |
| Yucatan Limited | Arts & recreation | 2016 |
| Zalion Ltd | Information & communication | 2016 |
| Zaman Properties Ltd | Real estate | 2023 |
| Zeera (Lyneham) Limited | Hospitality | 2020 |
| Zela Automotive Limited | Wholesale & retail | 2014 |
| Zella Social Ltd | Other services | 2026 |
| Zenave Projects Ltd | Professional & scientific | 2021 |