| We-Aid Limited | Information & communication | 2024 |
| Webb Teasdale Accountancy Ltd. | Professional & scientific | 2016 |
| Webb's (Wantage) Limited | Transport & logistics | 2006 |
| Wedding Safe Ltd | Information & communication | 2021 |
| WEE Enterprises Limited | Professional & scientific | 2019 |
| Well Preserved Limited | Extraterritorial | 2007 |
| Wellness Consulting Services Limited | Health & social care | 2023 |
| West Plus West Ltd | Construction | 2013 |
| Westcot Services Ltd | Construction | 2021 |
| Westside International Limited | Wholesale & retail | 2000 |
| Wetherall Landscaping Ltd | Administrative & support | 2025 |
| WG Carpentry and Construction Ltd | Manufacturing | 2020 |
| WGP Trustees Limited | Other services | 2011 |
| Wheatsheaf Restorations Limited | Real estate | 1998 |
| Where's the ME in MUM Ltd | Wholesale & retail | 2026 |
| White Coco Limited | Wholesale & retail | 2005 |
| White Gold Investments Limited | Financial services | 2022 |
| White Horse Fire and Security Limited | Administrative & support | 2014 |
| White Horse Renewables Ltd | Construction | 2023 |
| White Horse Scaffolding Ltd | Construction | 2020 |
| Whitehorse Land Management Ltd | Households | 2018 |
| Whitehorse Plumbing and Heating Ltd | Construction | 2020 |
| Whitehorse Renovations Ltd | Construction | 2018 |
| Whitford & Sons Farming Ltd | Agriculture & fishing | 2025 |
| WHM Cryogenic Services Limited | Manufacturing | 2026 |
| Whole Health Agriculture | Education | 2018 |
| Wholehog Media Ltd | Information & communication | 2021 |
| Wila Group Limited | Professional & scientific | 2004 |
| Wild Wickets Limited | Wholesale & retail | 2014 |
| Wildman Design Ltd. | Information & communication | 2006 |
| Wilkins-It Ltd | Agriculture & fishing | 2011 |
| Williams F1 Limited | Extraterritorial | 2008 |
| Williams Grand Prix Engineering Services LLP | | 2025 |
| Williams Grand Prix Technologies Limited | Professional & scientific | 2024 |
| Willmott Property Support Ltd | Administrative & support | 2016 |
| Willowside Developments Ltd | Real estate | 2018 |
| Winckelhohe Hunting Opportunities Ltd | Arts & recreation | 2016 |
| Wind and Waves Creations Ltd | Wholesale & retail | 2025 |
| Wind Business Support Ltd | Professional & scientific | 2012 |
| Windrush Anaesthesia Ltd | Health & social care | 2023 |
| Wine Noise Limited | Administrative & support | 2015 |
| Winsum Ltd | Professional & scientific | 2022 |
| Winterfox Ltd | Information & communication | 2025 |
| Wisdom Loom Ltd | Wholesale & retail | 2025 |
| WJ Design & Build Ltd | Construction | 2017 |
| Woodbury Manor Ltd | Wholesale & retail | 2024 |
| Woodcock Clothing Limited | Wholesale & retail | 2017 |
| Woods Farm (East Hendred) Limited | Agriculture & fishing | 1937 |
| Woolpack Manco Limited | Households | 2017 |
| World Wide Installations Ltd | Construction | 2011 |
| Worlledge Associates Limited | Professional & scientific | 2014 |
| Worters (London) Limited | Construction | 1945 |
| Wright Aviation Ltd | Manufacturing | 2020 |
| Wrightune Ltd | Wholesale & retail | 2011 |
| Wrmf Greentec Ltd | Extraterritorial | 2016 |
| WS Westwood Solutions Limited | Construction | 2025 |
| Wtsn Consultancy Ltd | Professional & scientific | 2020 |
| WUE Limited | Wholesale & retail | 2006 |
| Wychwood Investments Limited | Professional & scientific | 2013 |
| X41 Limited | Information & communication | 2016 |
| Xantra Ltd | Wholesale & retail | 2025 |
| Xenex Capital Ltd | Financial services | 2022 |
| XHY Therapy Limited | Other services | 2024 |
| Yard and Stable Hygiene Services Ltd | Other services | 2013 |
| YEW Tree Vineyard Ltd | Agriculture & fishing | 2016 |
| Your Property Expert Limited | Real estate | 2022 |
| Yummy Thai Restaurant Ltd | Hospitality | 2023 |
| Z&W Property Management Limited | Households | 2024 |
| Zeesneaks Ltd | Wholesale & retail | 2020 |
| Zerifas Consulting Ltd | Information & communication | 2019 |
| Zero Seconds London Ltd | Professional & scientific | 2018 |
| Zero Student Living Limited | Real estate | 2025 |
| Zoha Logistics Ltd | Transport & logistics | 2019 |