| York Court (Leighton Buzzard) Management Company Limited | Households | 2025 |
| York House Centre (Stony Stratford) | Education | 2007 |
| York House Investment Holdings Limited | Real estate | 2024 |
| Yorke Long & Co. Limited | Financial services | 1964 |
| Yorkleigh Contracts Limited | Construction | 2003 |
| Yotra Limited | Transport & logistics | 2017 |
| YOU & Yours Financial Services Ltd | Professional & scientific | 2021 |
| YOU and ME: in Step Ltd | Education | 2024 |
| YOU Investment Group Limited | Financial services | 2021 |
| YOU Love to SEE IT (UK) Limited | Information & communication | 2026 |
| YOU Matter.Global Limited | Administrative & support | 2017 |
| YOU Mental CIC | Education | 2023 |
| You-Dey International Holdings Limited | Financial services | 2026 |
| Youcloud UK Limited | Information & communication | 2024 |
| Young Empire CIC | Information & communication | 2022 |
| Young Fairy Limited | Wholesale & retail | 2023 |
| Young Galaxy Ltd | Wholesale & retail | 2021 |
| Young Investment Properties Limited | Administrative & support | 2013 |
| Youngkii Limited | Wholesale & retail | 2013 |
| Youngland Ltd | Wholesale & retail | 2012 |
| Youni Retreats Ltd | Health & social care | 2023 |
| Younited Ltd | Other services | 2023 |
| Your Absolute Mind Limited | Health & social care | 2021 |
| Your AC Ltd | Professional & scientific | 2018 |
| Your Airport Express Car Ltd | Transport & logistics | 2014 |
| Your Casa Ltd | Real estate | 2026 |
| Your Company Matters Limited | Professional & scientific | 2005 |
| Your Compliance Matters Limited | Professional & scientific | 2009 |
| Your Doorstep Services Limited | Administrative & support | 2014 |
| Your Event Supplier Ltd | Administrative & support | 2023 |
| Your FAV Nanny Ltd | Health & social care | 2020 |
| Your Local Advertising Ltd | Professional & scientific | 2024 |
| Your Major Transport Ltd | Wholesale & retail | 2023 |
| Your Path Ltd | Administrative & support | 2020 |
| Your Precious Gems Limited | Administrative & support | 2017 |
| Your Property Portal Ltd | Households | 2025 |
| Your VC Limited | Financial services | 2024 |
| Your VC Partners LLP | | 2011 |
| Your Whois Privacy Limited | Information & communication | 2008 |
| Yourcash ATM Systems Limited | Financial services | 2004 |
| Yourcash Holdings Limited | Financial services | 2010 |
| Yourcash Limited | Financial services | 2000 |
| Yourcash Solutions Limited | Financial services | 2013 |
| Yourgrant Limited | Professional & scientific | 2023 |
| Yourpcm Limited | Professional & scientific | 2019 |
| Yourpropertyportalmk Ltd | Real estate | 2025 |
| Yousfani Accounting Services Limited | Professional & scientific | 2015 |
| Yousfani Services Limited | Professional & scientific | 2019 |
| Yousmary Property Limited | Real estate | 2026 |
| Yousq Platforms Ltd | Information & communication | 2024 |
| Youth of Utkal CIC | Health & social care | 2024 |
| Youth Talent Skills CIC | Education | 2026 |
| Youthful Planet Ltd | Wholesale & retail | 2019 |
| Youwe Private Limited | Real estate | 2024 |
| Yowzer Limited | Manufacturing | 2004 |
| Yoyo Fast Ltd | Transport & logistics | 2019 |
| YPV 1 Ltd | Real estate | 2019 |
| YPV Building Services Ltd | Construction | 2025 |
| YRK Education UK Limited | Professional & scientific | 2025 |
| YS Research and Consulting Ltd | Professional & scientific | 2015 |
| Ys-Ha Capital Limited | Extraterritorial | 2023 |
| Ysan Enterprise Ltd | Administrative & support | 2025 |
| YSJ Group Consulting Ltd | Information & communication | 2023 |
| YSJ Properties Ltd | Real estate | 2025 |
| YT Properties Holdings Ltd | Real estate | 2025 |
| YTL Technologies Limited | Information & communication | 2024 |
| YU YAN KJ Ltd. | Wholesale & retail | 2025 |
| Yuan LI Ltd. | Wholesale & retail | 2025 |
| Yuan Xiang Ltd. | Wholesale & retail | 2025 |
| YUE YI CEN Ltd. | Wholesale & retail | 2025 |
| Yueli Cultural Media Ltd | Wholesale & retail | 2024 |
| YUF Management Ltd | Hospitality | 2024 |
| Yugao HEN Ltd. | Wholesale & retail | 2025 |
| Yujie KJ Ltd. | Wholesale & retail | 2025 |
| Yummex Synergy Limited | Wholesale & retail | 2025 |
| Yunderup Limited | Households | 2016 |
| Yunie Ltd | Information & communication | 2026 |
| Yunique Care Services Limited | Health & social care | 2015 |
| Yves Samuel Steve Limited | Construction | 2024 |
| Yvonnetee Limited | Public administration | 2023 |
| YW Bing Ltd. | Wholesale & retail | 2025 |
| YW Taxi MK Ltd | Transport & logistics | 2026 |
| YY88 Ltd | Transport & logistics | 2023 |
| YZY Auto Limited | Wholesale & retail | 2025 |
| Z Autoz Limited | Wholesale & retail | 2019 |
| Z I H Properties Ltd | Real estate | 2024 |
| Z M Property Management Limited | Real estate | 2018 |
| Z&K Milton Keynes Ltd | Hospitality | 2022 |
| Z&M Estates Ltd | Real estate | 2024 |
| Z&M International Ltd | Wholesale & retail | 2012 |
| Z&S Exclusive Limited | Real estate | 2024 |
| Z&X Corporate Limited | Extraterritorial | 2019 |
| Zaabel Healthcare Ltd | Health & social care | 2019 |
| Zaash Ltd | Real estate | 2020 |
| Zabox Ltd | Information & communication | 2022 |
| Zabs Enterprise Ltd | Information & communication | 2014 |
| Zachary Oliver Ltd | Professional & scientific | 2022 |
| Zaheer Horizons Ltd | Transport & logistics | 2025 |
| Zahum Technologies Ltd | Wholesale & retail | 2017 |
| Zainvlt Ltd | Administrative & support | 2026 |