| Waveprime Limited | Wholesale & retail | 2025 |
| Wavey Wizards Limited | Administrative & support | 2023 |
| WB Capital Limited | Financial services | 2026 |
| Wbbd Ltd | Professional & scientific | 2024 |
| WE Money Limited | Financial services | 2008 |
| Web Ellis Limited | Administrative & support | 2021 |
| Weightproud Limited | Real estate | 1992 |
| Welcome Stay Ltd | Administrative & support | 2018 |
| Welcome Stay Management Ltd | Hospitality | 2023 |
| Welding Kingdom Ltd | Manufacturing | 2023 |
| Welham Manor Residents Association (Welham Green) Limited | Households | 1984 |
| Welham Travel Limited | Transport & logistics | 2009 |
| Welhat Homeplan Ltd | Construction | 2023 |
| Wellsite Software Ltd | Information & communication | 2014 |
| Welwyn & Hatfield Conservative Association Limited | Other services | 1993 |
| Welwyn Hatfield Citizens Advice Bureau | Information & communication | 1997 |
| Wembley Park Management Company Limited | Households | 2003 |
| Wenz International Trading Ltd | Wholesale & retail | 2025 |
| Weslei Electrical Services Ltd | Construction | 2025 |
| West Court Management Limited | Households | 1981 |
| West END DAN Limited | Education | 2024 |
| Weston Beauty Clinic Limited | Other services | 2017 |
| Westward Properties Ltd | Transport & logistics | 1993 |
| Weybridge Demolition Limited | Construction | 2014 |
| WHI Accountant & Tax Adviser Ltd | Professional & scientific | 2011 |
| White Cliffs Water Limited | Extraterritorial | 1998 |
| Whitebrick Studios Limited | Construction | 2016 |
| Whitehill Gardens Residential Management Company Limited | Households | 2022 |
| Whiterock Limited | Real estate | 1994 |
| Whiterock Rental Group Limited | Real estate | 2015 |
| Whole Heart Ministries Ltd | Professional & scientific | 2016 |
| Wictoria TD Limited | Construction | 2016 |
| Wifi Partners Limited | Information & communication | 2019 |
| Wilgenry Group Holdings Limited | Financial services | 2023 |
| Wilkins Green Limited | Households | 2025 |
| Will Perez Ltd | Information & communication | 2026 |
| William Douglas Acquisitions Limited | Construction | 2026 |
| Willow House Management (Hatfield) Limited | Real estate | 2017 |
| Willow Lodge (Freehold) Limited | Households | 1997 |
| Willow Lodge Management Company Limited | Households | 1985 |
| Willowdene Court (Freehold) Limited | Real estate | 2001 |
| WIN Style Building Ltd | Manufacturing | 2018 |
| Wincity Company Limited | Real estate | 1994 |
| Windsor Court (Golders Green Road NW11) South Block Management Limited | Households | 1976 |
| Winforton Investments Limited | Financial services | 2021 |
| Wingfield Road Management Company Limited | Households | 2024 |
| Winmont Limited | Professional & scientific | 2024 |
| Winnas Circle Ltd | Wholesale & retail | 2024 |
| Winnie Alexio Ltd | Health & social care | 2019 |
| Wisami Property Limited | Real estate | 2024 |
| Wise Accountants Ltd | Professional & scientific | 2015 |
| Wise Living Network Limited | Information & communication | 2018 |
| Wise Words Speech Therapy Limited | Health & social care | 2018 |
| Wise Worksafe Limited | Administrative & support | 2012 |
| With Relish Limited | Information & communication | 2005 |
| Withe Ltd | Transport & logistics | 2021 |
| Without END Photography Ltd | Extraterritorial | 2024 |
| Wiwuga Capital Ltd | Real estate | 2022 |
| WLD Properties Limited | Manufacturing | 2017 |
| Woffinden Limited | Other services | 2015 |
| Wolfa Street Limited | Real estate | 2023 |
| Women Aspiring Great Success Limited | Manufacturing | 2019 |
| Women for More International CIC | Administrative & support | 2023 |
| Wood Build Management Ltd | Households | 2022 |
| Wood Vale 1958 Limited | Extraterritorial | 2013 |
| Woodchurch Limited | Real estate | 2015 |
| Woodcote Painting Contractors Limited | Construction | 1980 |
| Woodhill Security Limited | Administrative & support | 2015 |
| Woodhouse Contracts Holdings Limited | Extraterritorial | 2015 |
| Woodhouse Contracts Limited | Construction | 2015 |
| Woodland Software Solutions Limited | Financial services | 1998 |
| Woodside Mews (Leavesden) Management Company Limited | Households | 2019 |
| Woodside Place Management Limited | Households | 1991 |
| Woon Associates Ltd | Professional & scientific | 2015 |
| World Golf Tours Ltd | Administrative & support | 2024 |
| World of Dinosaurs Private Limited | Wholesale & retail | 2024 |
| World PR Media Limited | Manufacturing | 2022 |
| Worldtech Software Solutions Limited | Information & communication | 2004 |
| WORLDWIDE1Z Limited | Arts & recreation | 2024 |
| Wovra Textiles Ltd | Manufacturing | 2025 |
| Wright GAS Limited | Construction | 2021 |
| Wright Signs & Coachworks Limited | Manufacturing | 1961 |
| Wrong Fuel Experts Ltd. | Administrative & support | 2025 |
| Wrong Fuel Specialists Ltd | Professional & scientific | 2026 |
| Wsfc Limited | Administrative & support | 2022 |
| Wychwood Flooring Ltd | Wholesale & retail | 2013 |
| Wyebridge Investments Limited | Financial services | 2022 |
| Wyllyn International Ltd | Construction | 2019 |
| Xcess Milano Ltd | Wholesale & retail | 2020 |
| Xcuts Ltd | Administrative & support | 2022 |
| Xenode Limited | Information & communication | 2022 |
| XIR Quality Ltd | Arts & recreation | 2025 |
| XP Media Ltd | Manufacturing | 2025 |
| Xpert Logistics Limited | Transport & logistics | 2019 |
| XTZ Trans Ltd | Transport & logistics | 2023 |
| Xway Ltd | Transport & logistics | 2025 |
| Yarl (Media) Vision Ltd | Wholesale & retail | 2023 |
| Yarl Petroleum Limited | Wholesale & retail | 2013 |
| Yasi Ltd | Hospitality | 2026 |
| Yatri Foods Ltd | Wholesale & retail | 2022 |