| Wright Refinishing Supplies Limited | Wholesale & retail | 2013 |
| Wrightpath Project Controls Ltd | Professional & scientific | 2026 |
| Wrightpc Ltd | Other services | 2021 |
| Wrights Landscapes Limited | Administrative & support | 2015 |
| Wrvs Services Welfare Limited | Health & social care | 1993 |
| WST Engineering Holdings Limited | Manufacturing | 1992 |
| WT Window and Door Installations Ltd | Construction | 2024 |
| WTC Door Services Limited | Manufacturing | 2022 |
| Wtst Ltd | Education | 2024 |
| Wulfrun House Limited | Real estate | 1985 |
| WXM Assistance Ltd | Administrative & support | 2024 |
| Wychmark Limited | Real estate | 2013 |
| Wyim Ltd | Administrative & support | 2026 |
| Wymars UK Ltd | Wholesale & retail | 2020 |
| Wynters Travel Ltd | Transport & logistics | 2023 |
| Wyvern Plumbing Ltd | Construction | 2025 |
| X Apparel Limited | Wholesale & retail | 2024 |
| X400CARE Limited | Health & social care | 2025 |
| XAI UK Limited | Professional & scientific | 2012 |
| Xapper Limited | Construction | 2020 |
| Xavicom Limited | Manufacturing | 2007 |
| Xceed Professional Services Ltd | Manufacturing | 2023 |
| Xcelvillas Limited | Construction | 2019 |
| XCH Electrical Limited | Construction | 2013 |
| Xentarilova Ltd | Wholesale & retail | 2026 |
| Xerital Limited | Manufacturing | 2004 |
| Xidma Worldwide Services Ltd | Wholesale & retail | 2022 |
| Xiomara DE LA Casa Ltd | Real estate | 2019 |
| Xiujuan Dragon Limited | Hospitality | 2026 |
| XL Global Investments Ltd | Construction | 2026 |
| XL International Ltd | Transport & logistics | 1999 |
| Xoventa Global Ltd | Wholesale & retail | 2025 |
| Xpert Recruitment Solutions Limited | Administrative & support | 2017 |
| Xpert Tech Solutions Ltd | Administrative & support | 2024 |
| Xpert Ventures Limited | Extraterritorial | 2018 |
| Xraic Ltd | Information & communication | 2018 |
| Xtrutech Ltd | Professional & scientific | 2002 |
| Xuanqi Ltd | Hospitality | 2024 |
| Xylo (UK) Ltd | Wholesale & retail | 2010 |
| Y & H Contractors Limited | Construction | 2026 |
| Y Capel Management Ltd | Households | 2023 |
| Y R Properties & Developments Ltd | Construction | 2026 |
| Y&C Cafe Ltd | Hospitality | 2024 |
| Yachtify Limited | Information & communication | 2018 |
| Yahya Grill Ltd | Hospitality | 2023 |
| Yahya's Diner Ltd | Hospitality | 2026 |
| Yahya's Grill Ltd | Hospitality | 2022 |
| Yanah Foods Limited | Wholesale & retail | 2026 |
| Yarnfield Croft Management Co Ltd | Households | 2009 |
| YAS Construction Ltd | Construction | 2024 |
| Yash Cultural Academy UK Ltd | Education | 2024 |
| Yash Mini Market Ltd | Wholesale & retail | 2025 |
| Yashikaretailers Ltd | Wholesale & retail | 2023 |
| Yasmer Ltd | Wholesale & retail | 2025 |
| Yates Yard Limited | Households | 2004 |
| Yello Dog Design Ltd | Professional & scientific | 2019 |
| Yellow Stor Limited | Extraterritorial | 2011 |
| Yeoldebullandbush Ltd | Hospitality | 2025 |
| YES Appliance Rentals Ltd | Administrative & support | 2016 |
| YES Lease Limited | Administrative & support | 2013 |
| Yeslove! Ltd | Information & communication | 2023 |
| Yima Fulfilment Ltd | Transport & logistics | 2026 |
| Ying TAI (U.K.) Limited | Professional & scientific | 2000 |
| YLB Properties Ltd | Real estate | 2025 |
| YM Lopes Limited | Information & communication | 2015 |
| Ymam Properties Ltd | Hospitality | 2025 |
| Ynys Faelog Limited | Real estate | 2021 |
| Yobz Groups Ltd | Hospitality | 2023 |
| York Residential Rentals Ltd | Real estate | 2022 |
| Yorkshire Fisheries Ltd | Hospitality | 2025 |
| Yoruba Community Stoke-On-Trent CIC | Hospitality | 2024 |
| Yoshi's Sweets and Treats Limited | Wholesale & retail | 2024 |
| YOU & YOU Limited | Wholesale & retail | 2022 |
| YOU & Yours Personalised Ltd | Wholesale & retail | 2026 |
| YOU &ME Creations Ltd | Wholesale & retail | 2025 |
| YOU Aesthetics Staffordshire Limited | Other services | 2024 |
| YOU CAN DO IT Training Ltd | Education | 2021 |
| YOU CAN Find IT Training Ltd | Extraterritorial | 2022 |
| YOU Films Limited | Information & communication | 2021 |
| You'Re Home Property Ltd | Real estate | 2023 |
| Youchow Limited | Wholesale & retail | 2024 |
| Young and Cheeky Limited | Wholesale & retail | 2013 |
| Young Marmalade Limited | Wholesale & retail | 2003 |
| Your Business Buddies Ltd | Hospitality | 2025 |
| Your City Festival Ltd | Other services | 2019 |
| Your Digilab Ltd | Information & communication | 2024 |
| Your Future Home Limited | Real estate | 2014 |
| Your Home Investments Limited | Real estate | 2020 |
| Your Home OUR Property Limited | Real estate | 2025 |
| Your IT Specialist Ltd | Information & communication | 2022 |
| Your Plumbing and Drainage Services Limited | Construction | 2025 |
| Your Repair Limited | Construction | 2014 |
| Your Space Property Developments Limited | Construction | 2020 |
| Your Space Property Investments Ltd | Real estate | 2019 |
| Your Space Property Rentals Ltd | Real estate | 2019 |
| Your Space Supported Living Ltd | Real estate | 2023 |
| Yourcare Repairs Ltd | Construction | 2019 |
| Yourcare Services Ltd | Construction | 2015 |
| Yourkeys Lettings Ltd | Real estate | 2024 |
| Yourrender Ltd | Construction | 2019 |