| Wilkhu Property Limited | Real estate | 2023 |
| Wilkinson Electrical Ltd | Construction | 2019 |
| Willesden Sunday Club Ltd | Education | 2025 |
| William FRY Ltd | Construction | 2023 |
| William IV Street Management Company Limited | Households | 1997 |
| Willows Holdings Ltd | Households | 2026 |
| Willowtree Marina Residents Company Limited | Households | 1989 |
| Willsson&Co Ltd | Transport & logistics | 2013 |
| Wilson Bros Electrical Limited | Construction | 2020 |
| Wilton Park House and Estate Management Company Limited | Households | 2026 |
| Wimbledon Bridge House Management Company Limited | Households | 2026 |
| Wimpole Limited | Information & communication | 1999 |
| WIN Superstore Ltd | Wholesale & retail | 2019 |
| WIN WIN Technologies Ltd | Information & communication | 2025 |
| Winazurecloud Ltd | Wholesale & retail | 2019 |
| Windermere Impex Ltd | Wholesale & retail | 2023 |
| Windhaven Investments Ltd | Real estate | 2013 |
| Windmill Furniture Limited | Manufacturing | 2010 |
| Windows & Doors Fixing Ltd | Construction | 2023 |
| Windsong Productions Ltd | Administrative & support | 2026 |
| Wings of Soul Ltd | Professional & scientific | 2022 |
| Winkfield Developments Ltd | Construction | 2022 |
| Winkfield ROW Developments Ltd | Real estate | 2024 |
| Winkfield ROW Properties Limited | Real estate | 2025 |
| Winkster Lighting Limited | Other services | 2011 |
| Winner Construction Ltd | Construction | 2020 |
| Winnow House Management Company Limited | Households | 2017 |
| Winstanley Management Company Limited | Real estate | 1988 |
| Winze 136 Limited | Public administration | 2025 |
| Wire Hawk Ltd | Information & communication | 2025 |
| Wise Cyber Ltd | Information & communication | 2021 |
| Wise Electrical Developments Limited | Construction | 2003 |
| Wise Visionary Ventures Ltd | Professional & scientific | 2023 |
| Wisecars Group Ltd | Wholesale & retail | 2014 |
| Wisecars Ltd | Wholesale & retail | 2019 |
| Wisechoice Autocare Ltd | Wholesale & retail | 2026 |
| Wiseguy Media Ltd | Information & communication | 2012 |
| Wiserap Management Ltd | Construction | 2025 |
| Witcher Construction Ltd | Construction | 2020 |
| Witney Foods Ltd | Wholesale & retail | 2024 |
| Wize Accounting Ltd. | Professional & scientific | 2010 |
| WJG Metals Ltd | Construction | 2025 |
| WMK Constructions Ltd | Construction | 2026 |
| WMK Works Ltd | Construction | 2023 |
| Wnbaciu Ltd | Construction | 2025 |
| WOK and Go Management Ltd | Professional & scientific | 2019 |
| Woks Ltd | Hospitality | 2016 |
| Wolf Media Group Ltd. | Information & communication | 2019 |
| Wolf's Hairdressing Limited | Other services | 2012 |
| Wolfs Cake Limited | Manufacturing | 2023 |
| Wolsey Road (Sunbury) Limited | Households | 2013 |
| Wonderland Nursery Limited | Other services | 1992 |
| Woodbridge Civil Engineering Limited | Construction | 2013 |
| Woodend Estate Agents Ltd | Real estate | 2013 |
| Woodland Pizza Ltd | Wholesale & retail | 2014 |
| Woodlands Court Management (Kettering) Ltd. | Construction | 2015 |
| Woods Foodservice Limited | Wholesale & retail | 1982 |
| Woodside Property (AYR) Limited | Real estate | 2024 |
| Woodvalley Estates Limited | Real estate | 1998 |
| Wooflair Ltd | Wholesale & retail | 2025 |
| Woolly Rock Limited | Financial services | 2020 |
| Wooltech Limited | Professional & scientific | 2021 |
| Work Perfect (UK) Ltd | Education | 2015 |
| Workstreamz Limited | Professional & scientific | 2023 |
| World Box (UK) Limited | Information & communication | 1994 |
| World Bridge Food Ltd | Hospitality | 2020 |
| World EYE Vision Ltd. | Other services | 2018 |
| World Security Guards WSG Ltd | Administrative & support | 2024 |
| World Travel Protection Limited | Financial services | 2017 |
| Worldstories Limited | Construction | 2019 |
| Worldtestlabs Limited | Professional & scientific | 1997 |
| Worldwide Product Sourcing Limited | Administrative & support | 2009 |
| Worthyhold Property Management Limited | Households | 1989 |
| WPL Accounting Ltd | Professional & scientific | 2017 |
| WPQ Ltd | Wholesale & retail | 2024 |
| WRE Electrical Services Limited | Construction | 2009 |
| Wright Human Factors Limited | Professional & scientific | 2021 |
| WWW. Trade - Sales.Co.Uk Ltd | Wholesale & retail | 1999 |
| Wyatt Building Services (Ruislip) Limited | Construction | 2016 |
| Wyatt House Limited | Health & social care | 2001 |
| WYE Valley Care Limited | Health & social care | 2024 |
| Wyze Motors Ltd | Wholesale & retail | 2024 |
| XCCELER8 Ltd | Information & communication | 2022 |
| XEC Mango Ltd | Wholesale & retail | 2020 |
| Xerok Ltd | Information & communication | 2017 |
| Xerox (UK) Limited | Wholesale & retail | 1937 |
| Xerox Business Equipment Limited | Extraterritorial | 1984 |
| Xerox Capital (Europe) Limited | Financial services | 1995 |
| Xerox Computer Services Limited | Extraterritorial | 1980 |
| Xerox Distributor Operations Limited | Extraterritorial | 1996 |
| Xerox Equipment UK Limited | Wholesale & retail | 2016 |
| Xerox Exports Limited | Extraterritorial | 1952 |
| Xerox Finance Limited | Administrative & support | 1937 |
| Xerox Financial Services Canada Holdings Limited | Financial services | 2021 |
| Xerox Financial Services International Limited | Financial services | 2021 |
| Xerox Limited | Manufacturing | 1956 |
| Xerox Mailing Systems Limited | Extraterritorial | 1974 |
| Xerox Overseas Holdings Limited | Professional & scientific | 1996 |
| Xerox Products UK Limited | Wholesale & retail | 2016 |
| Xerox Professional Services Limited | Extraterritorial | 1997 |