| WVG Coaching Limited | Professional & scientific | 2020 |
| WW Holdings Limited | Financial services | 2000 |
| Wwmc Management Ltd | Real estate | 2017 |
| Wych Services Limited | Administrative & support | 2019 |
| Wych Tools Limited | Wholesale & retail | 2013 |
| Wymondley Barns Management Company Limited | Real estate | 2005 |
| Wyns Services Limited | Real estate | 2022 |
| WYP Consulting Ltd | Professional & scientific | 2023 |
| Xeedx Limited | Professional & scientific | 2014 |
| Xian Coms Limited | Information & communication | 2024 |
| Xonia Ella Ltd | Other services | 2022 |
| Xpert Digital Document Solutions (UK) Limited | Administrative & support | 2008 |
| Xpress Properties Limited | Real estate | 2015 |
| Xsel Solutions Limited | Professional & scientific | 2009 |
| Xyzzy Limited | Professional & scientific | 2013 |
| Y Infinity Ltd | Hospitality | 2025 |
| Yagmurlu Ltd | Hospitality | 2019 |
| YAQUB786 Ltd | Households | 2023 |
| Yellow Brick Education Ltd | Education | 2024 |
| Yellow Fields Investments Limited | Real estate | 2014 |
| Yellow Poplar Ltd | Other services | 2026 |
| Yookidz Limited | Information & communication | 2015 |
| York Group Limited | Financial services | 2017 |
| Yorkies Daycare | Health & social care | 2000 |
| Your ERA Ltd | Administrative & support | 2025 |
| Your Home Cover Limited | Other services | 2024 |
| Your Personal Finance Ltd | Financial services | 2013 |
| Your Tax Office Ltd. | Professional & scientific | 2005 |
| Youthcare Support Limited | Health & social care | 2021 |
| YTS Sushi Ltd | Hospitality | 2023 |
| Yuce's Cafe Ltd | Hospitality | 2025 |
| YUM YUM Thai Ltd | Wholesale & retail | 2019 |
| Yummy Foods Takeaway Ltd | Hospitality | 2023 |
| Yuncon Holding Ltd | Financial services | 2021 |
| Yyjs Limited | Construction | 2016 |
| Z G Stardust Logistics Limited | Transport & logistics | 2016 |
| Zacherino Limited | Arts & recreation | 2006 |
| Zaluvida Ventures Limited | Financial services | 2019 |
| Zanbilzone Ltd | Manufacturing | 2021 |
| ZAS Academy Ltd | Information & communication | 2025 |
| ZAS Consultancy Services Limited | Information & communication | 2014 |
| Zawislanski Ltd | Construction | 2015 |
| ZBA126 Ltd | Extraterritorial | 2015 |
| ZDR Productions Limited | Other services | 2025 |
| ZEE and Co Services Ltd | Wholesale & retail | 2024 |
| Zeia Ltd | Hospitality | 2025 |
| Zentrika Limited | Information & communication | 2025 |
| Zetweka-Uk: Print & Production Management Limited | Manufacturing | 2003 |
| ZHJ Design Ltd | Manufacturing | 2015 |
| Ziggurat Investments Limited | Real estate | 2025 |
| Zionson Care Limited | Real estate | 2024 |
| Zipcycle Ltd | Administrative & support | 2025 |
| ZJ Project Planning Ltd | Professional & scientific | 2017 |
| Zkyrocket Ltd | Information & communication | 2020 |
| Zondie Ltd. | Information & communication | 2017 |
| ZS Lettings Ltd | Real estate | 2021 |
| ZS RX Ltd | Administrative & support | 2022 |
| ZS Ventures Ltd | Transport & logistics | 2019 |
| Zynth Ltd | Information & communication | 2015 |