| Wellness Realty 1 Ltd | Real estate | 2018 |
| Wellness Realty 2 Ltd | Real estate | 2018 |
| Wellness Realty 3 Ltd | Real estate | 2025 |
| Wells Legal Ltd | Professional & scientific | 2024 |
| Wellspring Church (Watford) | Other services | 2007 |
| Wellsprings Group Ltd | Real estate | 2021 |
| Wellworth Care Limited | Administrative & support | 2016 |
| Welmax Properties Limited | Real estate | 2000 |
| Wema Properties Ltd | Real estate | 2023 |
| Wendy Chung London Limited | Professional & scientific | 2015 |
| Wenta | Information & communication | 1983 |
| Wenta Business Centres Limited | Construction | 1990 |
| Wenta Innovation (Stevenage) Limited | Administrative & support | 2003 |
| Wenzel Food Service Limited | Manufacturing | 2026 |
| Wenzels Franchise Limited | Wholesale & retail | 2025 |
| Wenzels Holdings Ltd | Wholesale & retail | 2024 |
| Wenzels Property Limited | Real estate | 2015 |
| Wenzels the Bakers Limited | Wholesale & retail | 2007 |
| Wescom Group Limited | Arts & recreation | 2005 |
| Wescombe Consulting Ltd | Professional & scientific | 2025 |
| Wessex Accounting Limited | Professional & scientific | 2015 |
| West Construction Services Limited | Construction | 2016 |
| West Directions Ltd | Professional & scientific | 2021 |
| West END Court Limited | Households | 1990 |
| West Group Security Ltd | Administrative & support | 2016 |
| West Herts ABC and Educational Support C.I.C. | Education | 2019 |
| West Line Group Ltd | Wholesale & retail | 2019 |
| West London MGH Ltd | Construction | 2021 |
| West One Bridging Limited | Financial services | 2010 |
| West One Capital Limited | Extraterritorial | 2014 |
| West One Commercial Mortgages Limited | Financial services | 2025 |
| West One Development Finance Holdings Limited | Administrative & support | 2018 |
| West One Development Finance Limited | Administrative & support | 2018 |
| West One Development Finance Midco Limited | Administrative & support | 2018 |
| West One Loan Limited | Financial services | 2005 |
| West One Secured Loans Holdings Limited | Administrative & support | 2015 |
| West One Secured Loans Limited | Financial services | 2015 |
| West Watford Community Association | Other services | 2010 |
| West-B Limited | Professional & scientific | 2007 |
| Westamerica Ltd | Information & communication | 2017 |
| Westcliff Cleaners Ltd | Other services | 2018 |
| Westcote House Ltd | Real estate | 2025 |
| Westcyber Ltd | Information & communication | 2019 |
| Westdown Signalling Limited | Professional & scientific | 2024 |
| Westernedge Limited | Wholesale & retail | 2025 |
| Westfield Academy | Education | 2013 |
| Westfield PRE School a Community Interest Company | Health & social care | 2018 |
| Westine Ecotech Ltd | Construction | 2022 |
| Westland CT Holdings Ltd | Financial services | 2023 |
| Westlands Care Home Limited | Health & social care | 2012 |
| Westminster Court (ST. Albans) Management Limited | Households | 1984 |
| Westminster Place Management Company (ST. Albans) Limited | Households | 1985 |
| Weston Close Freehold Ltd | Households | 2015 |
| Weston Close Management Company Limited | Households | 1994 |
| Westwick Place Management Company Limited | Households | 1989 |
| Westwinds Global Ltd | Professional & scientific | 2018 |
| Westwood Lodge (Friern Barnet) Management Company Limited | Households | 1968 |
| Wgcm Limited | Other services | 2019 |
| WGK Clinical Services Limited | Wholesale & retail | 2018 |
| WGK Consultancy Ltd | Professional & scientific | 2011 |
| WGK Ltd | Professional & scientific | 2021 |
| WGS Puttshack Nominees Limited | Administrative & support | 2015 |
| Wharf Villas Management Company Limited | Households | 1987 |
| What the Flavour Ltd | Hospitality | 2025 |
| Wheatley Tax Consulting Ltd | Professional & scientific | 2015 |
| Wheatoil Ltd | Wholesale & retail | 2025 |
| Wheel Deal CAB Services Limited | Transport & logistics | 2019 |
| Wheway Lifestyle International Limited | Professional & scientific | 1996 |
| Whip Kings Ltd | Wholesale & retail | 2025 |
| Whipp Construction Limited | Construction | 1993 |
| Whippduk Car Sales Ltd | Manufacturing | 2025 |
| Whippduk Ltd | Wholesale & retail | 2020 |
| Whippendell Block a Management Limited | Real estate | 1985 |
| Whippendell Block B Management Limited | Real estate | 1985 |
| Whisbro Mechanical Solutions Limited | Construction | 2006 |
| Whistlers CDG Limited | Financial services | 2023 |
| Whistlers Limited | Construction | 1990 |
| White Dog Studios Ltd | Information & communication | 2023 |
| White Heart Tattoo Collective Limited | Arts & recreation | 2018 |
| White Horse General UK Limited | Wholesale & retail | 2017 |
| White Pearl Smiles Limited | Health & social care | 2017 |
| White Rock T.C. Limited | Financial services | 2025 |
| White Shield Consulting Services Ltd | Administrative & support | 2011 |
| White Stone World Ltd | Real estate | 2024 |
| White Tiger Cleaning Limited | Administrative & support | 2009 |
| Whitedoor Services Limited | Professional & scientific | 2021 |
| Whites Science Innovation Limited | Wholesale & retail | 2011 |
| Whitewood Heating Limited | Construction | 2018 |
| Whitley and Tague Building Services Limited | Construction | 2007 |
| Whitney Davies Consulting Limited | Professional & scientific | 2015 |
| Whole Taste Ltd | Hospitality | 2024 |
| Wholesale Flowers-Plants Ltd | Wholesale & retail | 2024 |
| Wholesale to Retail Ltd | Wholesale & retail | 2017 |
| Wholesale Trading Supplies Limited | Wholesale & retail | 2002 |
| Wiarol Cleaning Ltd | Construction | 2024 |
| WIC Consulting Limited | Information & communication | 2011 |
| Wick Properties Limited | Real estate | 1958 |
| Wickes Building Supplies Limited | Wholesale & retail | 1984 |
| Wickes Finance Limited | Extraterritorial | 1986 |
| Wickes Group Holdings Limited | Financial services | 2019 |