| XPO Logistics Group Limited | Extraterritorial | 1977 |
| XPO Logistics Limited | Extraterritorial | 1991 |
| XPO Logistics Trustees Limited | Administrative & support | 2013 |
| XPO Logistics UK III Unlimited | Financial services | 2019 |
| XPO Maintenance UK Limited | Administrative & support | 2008 |
| XPO Transport Solutions UK Limited | Transport & logistics | 2008 |
| Xpress Cars Northampton Ltd | Transport & logistics | 2016 |
| Xpress Cars Northants Ltd | Transport & logistics | 2023 |
| Xpressvillage Limited | Transport & logistics | 2021 |
| XR8 Group Limited | Financial services | 2026 |
| XRM Commercial Ltd | Wholesale & retail | 2019 |
| Xrmechanical Ltd | Wholesale & retail | 2026 |
| Xscape Venue Ltd | Hospitality | 2023 |
| Xside Herbal Ltd | Wholesale & retail | 2024 |
| Xtinguish Ltd | Professional & scientific | 2021 |
| Xtinguish RM Ltd | Real estate | 2025 |
| Xtreme Cleaning Ltd | Administrative & support | 2010 |
| Xtreme Install Ltd | Construction | 2020 |
| Xtreme Management Solutions Ltd | Real estate | 2023 |
| Xtrmskills Limited | Construction | 2023 |
| XXL London Ltd | Hospitality | 2010 |
| Xynics Data Solutions Ltd | Professional & scientific | 2006 |
| XYZ & Daughters Ltd | Professional & scientific | 2023 |
| XYZ Bar Company Ltd | Hospitality | 2022 |
| XYZ Legals Ltd | Professional & scientific | 2024 |
| XYZ Property Development Ltd | Construction | 2023 |
| Xziox Distibution Ltd | Manufacturing | 2012 |
| Y Rebuild Ltd | Manufacturing | 2020 |
| Y&A Haffejee Ltd | Health & social care | 2016 |
| Y&J Consult Ltd | Information & communication | 2019 |
| Y2(UK) Ltd | Transport & logistics | 2025 |
| Y2K Action Limited | Professional & scientific | 1997 |
| YA Yuan Limited | Hospitality | 2022 |
| Yadayahweh Limited | Professional & scientific | 2019 |
| Yadnglad Limited | Real estate | 2023 |
| Yaleborn Limited | Professional & scientific | 2004 |
| Yamataxis Ltd | Transport & logistics | 2026 |
| Yameb Limited | Administrative & support | 2023 |
| Yanis Andrei Limited | Water & waste | 2019 |
| Yanis Gabriel Ltd | Construction | 2022 |
| Yapa Yapa Yapa Ltd | Hospitality | 2025 |
| Yappie Dayz Ltd | Transport & logistics | 2019 |
| Yaprak Burgess Hill Ltd | Hospitality | 2022 |
| Yarborough Care Ltd | Health & social care | 2019 |
| Yard & Foreign Ltd | Wholesale & retail | 2026 |
| Yardbourne Limited | Manufacturing | 2003 |
| Yardly Express Ltd | Hospitality | 2025 |
| Yasha & Co Ltd. | Wholesale & retail | 2014 |
| Yeasmin Property Limited | Real estate | 2015 |
| YEE LU FA Limited | Wholesale & retail | 2025 |
| Yelcool Ltd | Administrative & support | 2024 |
| Yellow Bourbon Coffee Roasters Limited | Manufacturing | 2016 |
| Yellow BUS Catering Limited | Hospitality | 2022 |
| Yellow Distributions Ltd | Wholesale & retail | 2026 |
| Yellow DOT (Andover) Limited | Education | 2011 |
| Yellow DOT (Chilworth) Limited | Education | 2009 |
| Yellow DOT (Eastleigh) Limited | Education | 2005 |
| Yellow DOT (Fair Oak) Limited | Education | 2014 |
| Yellow DOT (Hedge END) Limited | Education | 2011 |
| Yellow DOT (North Baddesley) Limited | Education | 2005 |
| Yellow DOT (Otterbourne) Limited | Education | 2012 |
| Yellow DOT (Romsey) Limited | Education | 2016 |
| Yellow DOT (Winchester) Limited | Education | 2014 |
| Yellow DOT Holdings Limited | Financial services | 2018 |
| Yellow DOT Limited | Education | 2003 |
| Yellow Mango Limited | Hospitality | 2025 |
| Yellow Tree Workforce Development Ltd | Education | 2018 |
| Yellowcircle Ltd | Extraterritorial | 2003 |
| Yellowtail Properties Limited | Real estate | 2013 |
| YEM UK Ltd | Wholesale & retail | 2022 |
| Yeomanry Court Management Company Limited | Households | 1999 |
| Yertjd Ltd | Manufacturing | 2026 |
| Yerusha RAY Ltd | Professional & scientific | 2026 |
| Yesterday Delivery Ltd | Transport & logistics | 2025 |
| Yewberry Property Ltd | Real estate | 2022 |
| Yewhew Limited | Information & communication | 2012 |
| YEZ Ltd | Information & communication | 2016 |
| YF Properties Limited | Hospitality | 1996 |
| YG Inspire Limited | Professional & scientific | 2017 |
| YHI Limited | Real estate | 2019 |
| Yhwh Properties Ltd | Real estate | 2025 |
| Yhyun Technology Limited | Wholesale & retail | 2026 |
| Yifang Oxfordqs Ltd. | Hospitality | 2019 |
| Yildiz Beren Bakery Limited | Hospitality | 2020 |
| Yili Reloved Ltd | Wholesale & retail | 2023 |
| Yilmaz Pizza Ltd | Hospitality | 2019 |
| Ying Lung Ltd | Hospitality | 2017 |
| Ying WA One Limited | Hospitality | 2021 |
| Yinka's Kitchen Limited | Hospitality | 2026 |
| YJK Limited | Health & social care | 2024 |
| YLA Creatives Ltd | Information & communication | 2015 |
| YLJ Properties Ltd | Real estate | 2023 |
| YN Property Ltd | Real estate | 2026 |
| YNOT2 Ltd | Hospitality | 2025 |
| YOB Customs Limited | Wholesale & retail | 2017 |
| Yodeska Limited | Administrative & support | 1993 |
| Yodheh Limited | Wholesale & retail | 2023 |
| Yoga Local Ltd | Other services | 2020 |
| Yohanandyuvan Properties Ltd | Real estate | 2023 |
| Yomin Limited | Hospitality | 2023 |