| Wynmark Holdings Limited | Financial services | 2012 |
| Wynsford Gardens Management Company Limited | Extraterritorial | 2020 |
| Wyzee Tree Limited | Wholesale & retail | 2025 |
| X L Architects LLP | | 2010 |
| XAE Group Limited | Professional & scientific | 2025 |
| Xarelo Limited | Transport & logistics | 2014 |
| Xbreach Security Services Ltd | Information & communication | 2012 |
| Xccommerce Ltd | Information & communication | 2021 |
| Xcel DOM Care Ltd | Health & social care | 2015 |
| Xdash Ltd | Transport & logistics | 2021 |
| XH Haulage Ltd | Transport & logistics | 2025 |
| Xiao Trading Ltd | Other services | 2017 |
| XM Services Limited | Administrative & support | 2013 |
| Xpandia Limited | Professional & scientific | 2004 |
| Xperts Move Ltd | Transport & logistics | 2021 |
| Xtremefitness Rugby Limited | Arts & recreation | 2024 |
| XTS Tribology Ltd | Professional & scientific | 2025 |
| YAM Solutions Ltd | Administrative & support | 2025 |
| Yardie Couture Cosmetics Ltd | Wholesale & retail | 2019 |
| YAS Empire Ltd | Real estate | 2025 |
| Yates Design and Build Limited | Construction | 2016 |
| Yates Estates (Midlands) Ltd | Construction | 2021 |
| YD26TECH Ltd | Information & communication | 2025 |
| YDK Limited | Manufacturing | 2017 |
| Yelfe Ltd | Wholesale & retail | 2022 |
| Yeomans Decor Limited | Construction | 2016 |
| YES! Logistics Solutions Limited | Extraterritorial | 2020 |
| YNG Consultancy Limited | Information & communication | 2025 |
| Yogi Enterprise Limited | Real estate | 2020 |
| Youngsamuels Ltd | Wholesale & retail | 2017 |
| Your Coaching Journey Ltd | Professional & scientific | 2021 |
| Your High Street Property Managers Limited | Real estate | 2024 |
| Your Life Three Sixty Limited | Information & communication | 2018 |
| Your Story Photography Limited | Professional & scientific | 2015 |
| Your Transport Partner Ltd | Transport & logistics | 2024 |
| Youth Property Limited | Real estate | 2023 |
| Yovel Software Technologies Ltd | Information & communication | 2026 |
| Ytsa Limited | Construction | 2026 |
| YUM YUM World Limited | Wholesale & retail | 2016 |
| Yurik Limited | Transport & logistics | 2022 |
| Yuvit Ltd | Information & communication | 2022 |
| Zajaczek Trans Ltd | Transport & logistics | 2013 |
| Zanta Consultancy Limited | Professional & scientific | 2020 |
| ZAV Accessories Ltd | Wholesale & retail | 2026 |
| Zayaan Private Limited | Manufacturing | 2024 |
| Zbober Trans Ltd | Transport & logistics | 2020 |
| Zcmm Consultants Limited | Professional & scientific | 2024 |
| ZEE Square Limited | Health & social care | 2011 |
| Zeemed Limited | Wholesale & retail | 2024 |
| Zenith Performance Limited | Education | 2020 |
| Zenithtec Solutions Limited | Information & communication | 2023 |
| Zentari Motors Limited | Wholesale & retail | 2026 |
| Zenvityx Ltd | Manufacturing | 2025 |
| Zephaniah Properties Ltd | Real estate | 2025 |
| Zero Point Million Limited | Wholesale & retail | 2021 |
| Zeropoint Chillers Limited | Extraterritorial | 2013 |
| Zeus Connex Limited | Information & communication | 2024 |
| Zeus Spedition Ltd | Transport & logistics | 2024 |
| Zhelevi Property Group Ltd | Construction | 2025 |
| Zigmund Ltd | Real estate | 2019 |
| Zigzag Nails Ltd | Other services | 2019 |
| Zlhkifc Fyigi Ltd | Wholesale & retail | 2025 |
| ZMD Ltd | Wholesale & retail | 2025 |
| Zontul Films Limited | Information & communication | 2007 |
| Zoost Ltd | Information & communication | 2007 |
| ZP Media Limited | Arts & recreation | 2026 |
| Zscaler Ecommerce Ltd | Wholesale & retail | 2025 |
| Zuiaigo Limited | Wholesale & retail | 2015 |
| Zydrunas Deigidenis Transport Limited | Transport & logistics | 2015 |
| Zyhealthcare Ltd | Wholesale & retail | 2022 |
| Zzwilliams Ltd | Real estate | 2024 |