| World of Tiles, Kitchens and Bathrooms Limited | Wholesale & retail | 2007 |
| World of Wars Ltd | Manufacturing | 2025 |
| World Sun Foods Ltd | Manufacturing | 2019 |
| Worldwide Trading Ltd | Wholesale & retail | 2015 |
| Worledge Property Ltd | Real estate | 2023 |
| Worm Purple Ltd | Information & communication | 2007 |
| Worx Financial Services Ltd | Other services | 2016 |
| Worx Motor Company Ltd | Wholesale & retail | 2019 |
| WOW Regional Mentoring Limited | Professional & scientific | 2017 |
| Wowaka Events Decor Ltd | Hospitality | 2025 |
| WP Sole Trustee Limited | Professional & scientific | 2019 |
| WP Vtech Ltd | Manufacturing | 2020 |
| WPM Engineering Ltd | Manufacturing | 2011 |
| WR Electrical Contractors Limited | Construction | 2003 |
| WR Surveying Ltd | Professional & scientific | 2023 |
| WR Surveying the Franchise Ltd | Professional & scientific | 2025 |
| Wrap Revolution Limited | Wholesale & retail | 2013 |
| Wreck-It Pro Limited | Construction | 2025 |
| Wreckerz Ltd | Construction | 2024 |
| Wren, Wolf & Hendrex Limited | Financial services | 2024 |
| Wright-Shaw Utilities Limited | Construction | 2022 |
| Wrightl Window Repairs Ltd | Construction | 2025 |
| Wrights Housing Ltd | Real estate | 2025 |
| Wristwise Limited | Health & social care | 2025 |
| Write and Wrong Ltd | Arts & recreation | 2023 |
| Write Business Right Limited | Public administration | 2021 |
| Writers of the World Ltd | Education | 2022 |
| WSR Consulting Ltd | Professional & scientific | 2019 |
| WSS Transport Ltd | Transport & logistics | 2025 |
| WTJ Services Ltd | Administrative & support | 2017 |
| WTL Kingdom Ltd | Education | 2021 |
| Wuddstudio Limited | Arts & recreation | 2025 |
| Wuracar Limited | Administrative & support | 2025 |
| Wushe Invest Limited | Financial services | 2019 |
| Wushe Investments Ltd | Financial services | 2023 |
| Wusheng (UK) Ltd | Hospitality | 2005 |
| WW Plus CIC | Education | 2023 |
| WW Properties (UK) Limited | Real estate | 2003 |
| WW Windows Limited | Construction | 2009 |
| Wyberton Management Company Limited | Real estate | 2021 |
| Wych Property Investments Ltd | Real estate | 2025 |
| WYE Buildings Limited | Real estate | 2022 |
| WYE PR Limited | Professional & scientific | 2022 |
| Wyndale (Holdings) Limited | Professional & scientific | 2001 |
| Wyndthorpe Electrical Limited | Construction | 2009 |
| Wysis Properties Limited | Real estate | 2024 |
| Wyvern Engineering Services Ltd | Professional & scientific | 2023 |
| Wyvern Management (Phase I) Limited | Real estate | 1993 |
| Wyvern Management (Plot 3000) Limited | Real estate | 1999 |
| Wyvern Management (Wyvern Court) Limited | Administrative & support | 2006 |
| X Fifteen Ltd | Wholesale & retail | 2024 |
| X Property Development Ltd | Real estate | 2021 |
| X Runner Ltd | Arts & recreation | 2009 |
| X-Fire Safety Solutions Limited | Administrative & support | 2024 |
| X-Plane Limited | Wholesale & retail | 2014 |
| XAK Investments Limited | Real estate | 2012 |
| Xandra Utility Ltd | Wholesale & retail | 2022 |
| Xantoria Games Ltd | Information & communication | 2022 |
| Xapool Limited | Other services | 2025 |
| Xaver Kreuz GmbH & Co Ltd | Extraterritorial | 2015 |
| Xcel Driving Academy Ltd | Education | 2026 |
| Xcel Energy Limited | Energy | 2021 |
| Xcelerate Academy Ltd | Education | 2023 |
| Xchange Mortgages Limited | Financial services | 2005 |
| Xchangex Network Ltd | Information & communication | 2025 |
| XCQ Ltd | Manufacturing | 2025 |
| Xcube Limited | Financial services | 2019 |
| XD Rail Ltd | Professional & scientific | 2010 |
| XDC Autonomous Solutions Ltd | Wholesale & retail | 2025 |
| Xelinia Properties UK Limited | Financial services | 2025 |
| Xelinia Properties UK M1 Limited | Real estate | 2025 |
| Xeropoint Ltd. | Information & communication | 2017 |
| Xiii Studios Ltd | Information & communication | 2024 |
| Xmas 1998 Limited | Professional & scientific | 1970 |
| Xpand Property Ltd | Real estate | 2024 |
| Xpertise Recruitment Limited | Administrative & support | 2012 |
| Xpress Computers & Mobiles Ltd | Wholesale & retail | 2019 |
| XS Trading Limited | Wholesale & retail | 2026 |
| XSB Properties Ltd | Real estate | 2025 |
| Xsmash Burger Ltd | Hospitality | 2025 |
| XWR 1 Limited | Construction | 2016 |
| XWR 2 Ltd | Construction | 2017 |
| XWR Basement Limited | Real estate | 2015 |
| XWR Holdings Limited | Professional & scientific | 2014 |
| XWR Investments Limited | Real estate | 2014 |
| XWR Limited | Real estate | 2011 |
| XXE Properties Ltd | Real estate | 2024 |
| Xxii Consulting Ltd | Professional & scientific | 2022 |
| XYS Property Ltd | Real estate | 2022 |
| XYZ Sales Consultants Ltd | Professional & scientific | 2017 |
| Y & a Limited | Health & social care | 2015 |
| Y & B Bakery (Hendon) Limited | Wholesale & retail | 2020 |
| Y & J Services Limited | Hospitality | 2018 |
| Y3M Connection Ltd | Hospitality | 2014 |
| Y?Marketing Limited | Professional & scientific | 2007 |
| Yaahoo Baahoo Ltd | Wholesale & retail | 2026 |
| Yabro Limited | Wholesale & retail | 2026 |
| Yacht Owners Club Ltd | Wholesale & retail | 2021 |
| Yada Collective CIC | Hospitality | 2020 |
| Yahya Vehicle Solutions Ltd | Transport & logistics | 2025 |