| Wharf Therapy Ltd | Real estate | 2019 |
| What the Flip Ltd | Hospitality | 2024 |
| Whdo Electrical Limited | Construction | 2021 |
| Whitaker Surgical Services Limited | Health & social care | 2019 |
| Whitchurch BIM Limited | Professional & scientific | 2017 |
| White Art Limited | Administrative & support | 2010 |
| White Collar Boxing London Ltd | Arts & recreation | 2013 |
| White Horse Farm Equestrian Centre Limited | Agriculture & fishing | 2013 |
| White Shelf Development Limited | Real estate | 2020 |
| Whitehall Residencies Limited | Real estate | 2018 |
| Whites Chimney Sweeps Limited | Administrative & support | 2017 |
| Whites Chimneys and Stoves Limited | Administrative & support | 2013 |
| Whiting Windows Ltd | Construction | 2026 |
| Whitstable Lifts Limited | Construction | 2019 |
| Whitstable Scuba Ltd | Arts & recreation | 2011 |
| Whizz - ARD Delivery Co. Ltd | Other services | 2009 |
| Wibberley Pereira Ltd | Professional & scientific | 2020 |
| Wide Open Images Ltd | Professional & scientific | 2022 |
| Wiggins & Wiggins Limited | Real estate | 2022 |
| Wildpower Consultancy Limited | Professional & scientific | 2024 |
| Wilford Mechanical Services Limited | Manufacturing | 2004 |
| Wilkes Estates Limited | Real estate | 2015 |
| Wilkins NO. 1 Limited | Administrative & support | 2000 |
| Willa Trading Ltd | Administrative & support | 2022 |
| Willbrooke Construction Services Limited | Construction | 2019 |
| William Arthur & Associates Limited | Administrative & support | 2008 |
| William Doherty Limited | Construction | 2023 |
| Willow Alexander Cleaning Ltd | Administrative & support | 2022 |
| Willow Alexander Gardeners Limited | Administrative & support | 2024 |
| Willow Alexander Handyman Limited | Other services | 2023 |
| Willow Alexander Window Cleaners Limited | Administrative & support | 2024 |
| Willow IT Solutions Ltd | Information & communication | 2025 |
| Willow Surveys Limited | Professional & scientific | 2014 |
| Willow Tree Solutions Ltd | Professional & scientific | 2024 |
| Willowcrest London Limited | Health & social care | 2025 |
| Willowocean Limited | Administrative & support | 2023 |
| Willsher Plant Hire Ltd | Administrative & support | 2004 |
| Wilmington New Homes 2 Limited | Construction | 2014 |
| Wilson & Sons Plumbing Limited | Construction | 2019 |
| Wilson Engineering Solutions Services Limited | Construction | 2024 |
| Wimbledon Education & Travel Company Limited | Administrative & support | 2014 |
| Wimpy B Ltd | Hospitality | 2026 |
| Wind Engineering Limited | Energy | 2016 |
| Windermere Flats Limited | Households | 1970 |
| Wingpitch Limited | Real estate | 1949 |
| Winmore Limited | Professional & scientific | 2025 |
| Winstone Properties Limited | Real estate | 1999 |
| Winterbell Limited | Administrative & support | 2018 |
| Winterfell Ventures Limited | Construction | 2014 |
| Winzar Developments Ltd | Real estate | 2023 |
| Wire Representation Ltd | Administrative & support | 2023 |
| Wisdom Support Limited | Health & social care | 2009 |
| Wisdom Support Services Limited | Health & social care | 2024 |
| Wise NUT Limited | Wholesale & retail | 2022 |
| Withnell & Partners Limited | Information & communication | 2018 |
| Wittynet Solutions Ltd | Construction | 2023 |
| Wizard Mechanical Ltd | Construction | 2025 |
| WL Integra Limited | Wholesale & retail | 2022 |
| Wokingham Property Limited | Real estate | 2012 |
| Wood Street Ventures Ltd | Financial services | 2026 |
| Woodgate Capital Management Limited | Other services | 2014 |
| Woodham Investments Limited | Construction | 2014 |
| Woodpecker Commercial Ventures (UK) Limited | Construction | 2021 |
| Woodside Wellness Rooms Ltd | Health & social care | 2022 |
| Woolwich Road 62 Limited | Real estate | 2017 |
| Workbox Studios Limited | Real estate | 2017 |
| Workfuly Ltd | Information & communication | 2022 |
| Workhouse#One Limited | Hospitality | 2012 |
| World Keeps Turning Ltd | Arts & recreation | 2020 |
| World Package Logistics Limited | Other services | 2014 |
| Worldwide Travel Group Ltd | Administrative & support | 2020 |
| Worth & Sterling Limited | Construction | 2014 |
| WOW Event Catering Limited | Hospitality | 2024 |
| WOW Taco Ltd | Hospitality | 2026 |
| Wren Mortgage Consultants Ltd | Financial services | 2015 |
| Wright-Tech UK Limited | Wholesale & retail | 2009 |
| WSF Install Limited | Construction | 2024 |
| Wynter Knight and Company Limited | Professional & scientific | 2010 |
| X&T Services Ltd | Administrative & support | 2025 |
| Xaghra Limited | Other services | 2024 |
| XCL Site Management Limited | Public administration | 2014 |
| XO Electrical Solutions Ltd | Construction | 2020 |
| Xtreme Roofing Limited | Construction | 2015 |
| XXV March Limited | Financial services | 2026 |
| Y&N Original Limited | Hospitality | 2022 |
| Y&T 2025 Limited | Administrative & support | 2025 |
| Yaad SPV Ltd | Real estate | 2024 |
| Yaad Ventures Ltd | Real estate | 2024 |
| Yacht Electronic Services (U.K.) Limited | Administrative & support | 1986 |
| Yana Global Limited | Information & communication | 2016 |
| Yanosa Ltd | Administrative & support | 2021 |
| Yarddog Limited | Real estate | 2019 |
| YB Beauty Ltd | Other services | 2024 |
| Yellow Life Coaching Ltd | Professional & scientific | 2014 |
| Yemicare Limited | Health & social care | 2018 |
| Yetikatt LLP | | 2015 |
| YIA Estates Ltd | Real estate | 2024 |
| Yigit EFE 2023 Ltd | Wholesale & retail | 2026 |
| Yiji Decoration Limited | Construction | 2021 |
| Ykey Limited | Administrative & support | 2014 |