| Wynyard Developments Limited | Construction | 2003 |
| Wynyard Estate Services Limited | Real estate | 1998 |
| Wynyard Estates Limited | Construction | 1984 |
| Wynyard Golf and Country Club Limited | Arts & recreation | 2004 |
| Wynyard Granary Management Limited | Other services | 2002 |
| Wynyard Hall Limited | Administrative & support | 2004 |
| Wynyard Homes Management Company Limited | Real estate | 2017 |
| Wynyard Padel Club Limited | Arts & recreation | 2025 |
| Wynyard Park (Estate Co) Limited | Extraterritorial | 2005 |
| Wynyard Park Holdings Limited | Financial services | 2017 |
| Wynyard Park Limited | Construction | 2005 |
| Wynyard Park Ventures LLP | | 2018 |
| Wynyard Property & Developments Limited | Real estate | 2021 |
| Wynyard Property Rentals Ltd | Real estate | 2020 |
| Wynyard Therapy & Life Coaching Services Limited | Health & social care | 2025 |
| Wynyard Vets Limited | Professional & scientific | 2024 |
| X Red Five Limited | Real estate | 2021 |
| Xaerus Performance Europe Limited | Wholesale & retail | 2026 |
| Xcellent Engagement Ltd | Administrative & support | 2023 |
| Xhale Living Ltd | Health & social care | 2024 |
| Xixi International Ltd | Real estate | 2016 |
| Xixi Opal LLP | | 2017 |
| Xtex Global Recruit Limited | Administrative & support | 2024 |
| Xtreme Graphics Signs and Engraving Ltd | Professional & scientific | 2012 |
| Xymel Ltd | Information & communication | 2026 |
| Xyron Ltd | Information & communication | 2019 |
| Y & M Yusuf WP Ltd | Administrative & support | 2024 |
| Yade Services Ltd | Wholesale & retail | 2026 |
| Yarm Plumbing & Heating Limited | Construction | 2004 |
| Yarm Property Ventures Ltd | Hospitality | 2016 |
| Yazdanpanahi Family Holdings Ltd | Real estate | 2019 |
| Yazdanpanahi Family Partnership LLP | | 2019 |
| Yellow Legacy Property Investment Ltd | Real estate | 2024 |
| Yellow Opal Ltd | Real estate | 2017 |
| Yeung Family Partnership LLP | | 2019 |
| YH Industrial Services Ltd | Construction | 2025 |
| Yiyi International Ltd | Real estate | 2020 |
| Yochana Ltd | Information & communication | 2025 |
| York Data Services Limited | Information & communication | 2003 |
| York Fibre Limited | Other services | 2024 |
| Yorkshire Rose Developments Limited | Real estate | 2002 |
| Yorkshire Rose Homes Limited | Real estate | 2005 |
| Yorkshire Rose Partnership LLP | | 2022 |
| Your Finances Limited | Financial services | 2018 |
| YRS Properties and Investments Ltd | Real estate | 2025 |
| Yusuf Yusuf LLP | | 2018 |
| Z & F Shamim WP Ltd | Administrative & support | 2024 |
| Z Sharif & L ZIA WP Ltd | Administrative & support | 2024 |
| ZAK Walker Plumbing and Heating Ltd | Construction | 2024 |
| Zamra Properties Ltd | Real estate | 2023 |
| Zarin Holdings Ltd | Real estate | 2024 |
| Zars Estates Limited | Real estate | 2025 |
| Zase WP Ltd | Administrative & support | 2024 |
| ZEN Family Partnership LLP | | 2020 |
| Zenith Analytics Limited | Health & social care | 2025 |
| Zero Suga Ltd | Hospitality | 2025 |
| Zerop Global Ltd | Wholesale & retail | 2023 |
| ZF Imaging Ltd | Health & social care | 2018 |
| Zhao LLP | | 2021 |
| ZIG ZAG Sail Charters Ltd | Hospitality | 2011 |
| Zikaba Services Limited | Health & social care | 2025 |
| Zinala Consulting Limited | Real estate | 2012 |
| Zircon Living Ltd | Hospitality | 2022 |
| ZN Homes Ltd | Real estate | 2024 |
| Zoel Limited | Professional & scientific | 2021 |
| Zutshi Family Holdings Ltd | Real estate | 2019 |
| Zutshi Family Partnership LLP | | 2019 |