| Wolverton Road Limited | Construction | 2024 |
| Women With a Purpose Limited | Information & communication | 2007 |
| Wonderlab IT Ltd | Information & communication | 2016 |
| Wonderland the Musical Ltd | Arts & recreation | 2015 |
| Wonderspace Studios Ltd | Professional & scientific | 2026 |
| Wonex Ltd | Wholesale & retail | 2024 |
| Wonkenstein Ltd | Information & communication | 2010 |
| Wooburn Green Ltd | Administrative & support | 2017 |
| Wooburn Green Property Ltd | Administrative & support | 2018 |
| Wood and Water Limited | Information & communication | 2015 |
| Woodbridge Car Services Ltd | Transport & logistics | 2000 |
| Woodcock Hill Estate Limited | Real estate | 1923 |
| Woodfield Facilities Limited | Administrative & support | 1986 |
| Woodfield Windows and Conservatories Limited | Construction | 2011 |
| Woodfield Windows Southern Limited | Manufacturing | 2017 |
| Woodford Surveys Limited | Professional & scientific | 2011 |
| Woodhill 45A Limited | Real estate | 2020 |
| Woodland Flooring Ltd | Construction | 2024 |
| Woodlands Park Holdings Ltd | Real estate | 2021 |
| Woodlands Park Investments Ltd | Real estate | 2021 |
| Woodmaterials Group LP | | 2020 |
| Woodscanner Ltd | Wholesale & retail | 2017 |
| Woodside (Reading) Limited | Real estate | 2019 |
| Woodsmiths Services Ltd | Administrative & support | 2025 |
| Woodspring Care at Home Ltd | Health & social care | 2023 |
| Wooduck Ltd | Wholesale & retail | 2024 |
| Woodview Court RTM Company Limited | Real estate | 2013 |
| Woodvine Services Limited | Information & communication | 2016 |
| Woodward Consulting Associates Ltd | Professional & scientific | 2015 |
| Woodworm and DRY ROT Co Limited | Professional & scientific | 1985 |
| Woody BBQ Ltd | Hospitality | 2026 |
| Woodyear Consulting Ltd | Information & communication | 2012 |
| Woody’S Express Ltd | Hospitality | 2019 |
| Wooldridge Contractors Limited | Construction | 1984 |
| Wooldridge Developments Ltd | Construction | 2001 |
| Woolrych Court RTM Company Limited | Other services | 2016 |
| Woolrych Properties Limited | Construction | 2013 |
| Wootton Close Management Limited | Real estate | 2015 |
| Word Person Games Limited | Information & communication | 2016 |
| Work the Plan Limited | Administrative & support | 2011 |
| Workr Solutions Limited | Professional & scientific | 2018 |
| Workr Umbrella Limited | Professional & scientific | 2014 |
| Workwell Accounting Limited | Extraterritorial | 2023 |
| Workwell Construction Limited | Extraterritorial | 2023 |
| Workwell Funding Limited | Extraterritorial | 2023 |
| Workwell Global Limited | Financial services | 2025 |
| Workwell Holdings Limited | Extraterritorial | 2023 |
| Workwell International Limited | Extraterritorial | 2023 |
| Workwell Oncore UK Ltd | Financial services | 2025 |
| Workwell Outsourcing Limited | Extraterritorial | 2023 |
| Workwell PAY & Bill Limited | Extraterritorial | 2023 |
| Workwell People Solutions Limited | Information & communication | 1989 |
| World Atlas Trade Ltd | Wholesale & retail | 2026 |
| World Diplomatic Organization (WDO) Ltd | Public administration | 2025 |
| World Engines Limited | Wholesale & retail | 1968 |
| World Golf Systems Limited | Arts & recreation | 1997 |
| World Golf Systems Nominees Ltd | Administrative & support | 2011 |
| World Groop of Aircondition LP | | 2018 |
| World Migration Services Limited | Professional & scientific | 2018 |
| World of Children’S Yoga Limited | Other services | 2019 |
| World Sailing Trust | Education | 2017 |
| Worldly Goods Ltd | Wholesale & retail | 2023 |
| Worldtell Limited | Information & communication | 2014 |
| Worldwide Aviation Services Ltd | Transport & logistics | 2015 |
| Worldwide Interns Ltd | Education | 2019 |
| Worldwide Studios Limited | Information & communication | 2016 |
| Worth Waiting for US Limited | Construction | 2022 |
| Worxzone Ltd | Construction | 2019 |
| Wotmole Limited | Construction | 2024 |
| WPA Support Services (Holdings) Limited | Professional & scientific | 2003 |
| WPA Support Services Limited | Construction | 2003 |
| WPS Nominees Limited | Administrative & support | 2024 |
| WPT Developments Ltd | Construction | 2021 |
| WR1A Ltd | Professional & scientific | 2023 |
| Wright Home Group Limited | Manufacturing | 2016 |
| Wrist Kings Limited | Wholesale & retail | 2022 |
| Wrkhutch Ltd | Information & communication | 2024 |
| Wrlara RTM Company Ltd | Households | 2019 |
| Wrtg Ltd | Transport & logistics | 2023 |
| WS Consultancy Ltd | Education | 2025 |
| WS Contractors Ltd | Construction | 2025 |
| WS IT Services Limited | Information & communication | 2018 |
| Wsppcs UK Limited | Professional & scientific | 2017 |
| Wspring Care Property Ltd | Real estate | 2022 |
| WSS Engineering Solutions Limited | Professional & scientific | 2011 |
| WST Landscapes Ltd | Construction | 2026 |
| WTE Promotions Ltd | Wholesale & retail | 2019 |
| WTS Properties Limited | Real estate | 2020 |
| WUD Medics & Consultancy Limited | Real estate | 2013 |
| Wularco UK Limited | Construction | 2021 |
| WUS (Watford) Ltd | Wholesale & retail | 2026 |
| Wut.Io Ltd | Information & communication | 2013 |
| Wynn Sinclair Ltd | Administrative & support | 2026 |
| WZK Sprzet & Pasze Ltd. | Wholesale & retail | 2017 |
| X Ainails Limited | Wholesale & retail | 2026 |
| X-Power Ideas Ltd | Information & communication | 2025 |
| X-Seed Technology Limited | Information & communication | 2023 |
| X10 Ventures Ltd | Administrative & support | 2024 |
| X4 Academy Limited | Education | 2025 |
| Xaver Consultancy Ltd | Professional & scientific | 2023 |