| X Five LLP | | 2025 |
| X2 Computers Ltd | Information & communication | 2025 |
| X8 Developments 2022 Limited | Real estate | 2022 |
| X8 Developments Limited | Real estate | 2020 |
| X8 Enterprise Limited | Real estate | 2017 |
| X8 Enterprise One Limited | Real estate | 2020 |
| X8 Properties Limited | Administrative & support | 2014 |
| Xclusive Yuvraaj Ltd | Hospitality | 2017 |
| XF Logistics Ltd | Transport & logistics | 2022 |
| XI Experience Improved Limited | Professional & scientific | 2025 |
| Xpres Glass Ltd | Manufacturing | 2017 |
| Xrotorz Limited | Professional & scientific | 2021 |
| Y L Advertisers Ltd | Hospitality | 2019 |
| Y&S Locums Ltd | Health & social care | 2014 |
| Y&S Properties Ltd | Real estate | 2016 |
| Yaagavi Ltd | Wholesale & retail | 2021 |
| Yang Star Limited | Hospitality | 2020 |
| Yasin and Ruman Ltd | Wholesale & retail | 2021 |
| YBY Engineering Ltd | Construction | 2023 |
| Ycfjq Ltd | Other services | 2025 |
| Yenoh Consulting Limited | Information & communication | 2013 |
| YES Chef Dining Northeast Ltd | Hospitality | 2023 |
| Yogist PVT Limited | Wholesale & retail | 2019 |
| Yolo Pizza Limited | Hospitality | 2025 |
| Yolo YOU Only Learn Once Motoring Academy Ltd | Education | 2020 |
| Yolopizza 1 Limited | Hospitality | 2026 |
| Yoni Isaacs Holdings Ltd | Real estate | 2023 |
| Yorkshire Tiger Limited | Transport & logistics | 2001 |
| Young’S Foodservice Ltd | Extraterritorial | 2024 |
| Your Digital Accountant Limited | Professional & scientific | 2018 |
| Your Home NE Ltd | Construction | 2020 |
| Your Houzez Limited | Real estate | 2020 |
| Your Moment Events Ltd | Professional & scientific | 2023 |
| Your Online Business Manager Ltd | Administrative & support | 2023 |
| Your Property Stager Limited | Other services | 2022 |
| Yours Mine and Ours Properties Ltd | Hospitality | 2019 |
| Youtunes Inc Limited | Information & communication | 2023 |
| Yowza Desserts Ltd | Hospitality | 2019 |
| YR Pharm Ltd | Wholesale & retail | 2022 |
| YS Services (NW) Ltd | Other services | 2018 |
| YSA Properties Ltd | Real estate | 2025 |
| Yummy 2 Go Limited | Hospitality | 2025 |
| Yummy Seaham Ltd | Hospitality | 2026 |
| YZ Systems Ltd | Manufacturing | 2004 |
| Z&A Properties Limited | Real estate | 2025 |
| Zadez Ltd | Hospitality | 2026 |
| Zaheer Locums Ltd | Wholesale & retail | 2018 |
| Zandi Barbers Ltd | Other services | 2023 |
| Zanganeh Ltd | Real estate | 2025 |
| Zanko Barber Shop Ltd | Other services | 2025 |
| Zaras Food Ltd | Hospitality | 2026 |
| Zare Pizza Ltd | Hospitality | 2026 |
| Zayan's Indian Ltd | Hospitality | 2018 |
| Zees Bundles Ltd | Wholesale & retail | 2026 |
| Zekes Media Ltd | Professional & scientific | 2023 |
| Zenith Construction & Home Improvements Limited | Construction | 2026 |
| Zenrx Limited | Professional & scientific | 2019 |
| Zentrimall Limited | Wholesale & retail | 2025 |
| Zeroten Technologies UK Ltd | Information & communication | 2024 |
| Zeus Innovation Limited | Information & communication | 2016 |
| ZF Electrical Ltd | Construction | 2026 |
| Zgjk Solutions Ltd | Real estate | 2024 |
| Zimmadar's Properties & Lettings Ltd | Real estate | 2026 |
| Zizu Properties Ltd | Real estate | 2024 |
| Zlotar Buildings Ltd | Construction | 2025 |
| Zola Health Care Limited | Health & social care | 2021 |
| Zomacare Ltd | Health & social care | 2021 |
| Zoonder Limited | Information & communication | 2009 |
| Zorotech Ltd | Information & communication | 2026 |
| ZRM 23 Ltd | Manufacturing | 2026 |
| ZSC Retail Ltd | Wholesale & retail | 2019 |
| Zugimpex Holding Limited | Professional & scientific | 2024 |