| Wsmc Investments Ltd | Real estate | 2018 |
| WTG Consultants Ltd | Education | 2023 |
| Wtml Developments Limited | Real estate | 2007 |
| Wukkr Properties Ltd | Real estate | 2023 |
| Wych ELM Services Ltd | Professional & scientific | 2014 |
| Wychwood Art Limited | Wholesale & retail | 2014 |
| Wykeham Fields Farm Limited | Agriculture & fishing | 2020 |
| Wykham Park Farm Limited | Agriculture & fishing | 2019 |
| Wyld Architects Limited | Professional & scientific | 2024 |
| Wynne Spray Coatings Ltd | Construction | 2018 |
| Wyvern Mouldings Limited | Manufacturing | 1978 |
| Wyvern Security Products Limited | Manufacturing | 1998 |
| X Property Ltd | Real estate | 2026 |
| X2 Developments Ltd | Construction | 2013 |
| XC Properties Ltd | Real estate | 2019 |
| Xcal AI Ltd | Information & communication | 2025 |
| XD Transport Limited | Construction | 2015 |
| XENON54 Engineering and Construction Ltd | Professional & scientific | 2022 |
| XML Summer School Limited | Information & communication | 2008 |
| Xpress Alloys London Limited | Manufacturing | 2016 |
| Y & Z Properties Ltd | Real estate | 2024 |
| YA Hayyu YA Qayyum Limited | Hospitality | 2025 |
| Yaminah Ltd | Hospitality | 2019 |
| Yard Safe Storage Ltd | Transport & logistics | 2025 |
| Yatim Ltd | Hospitality | 2025 |
| Yella Belly Limited | Manufacturing | 2025 |
| Yellow and Blue Nearshoring Ltd. | Information & communication | 2018 |
| Yelvertoft Marina Limited | Arts & recreation | 2008 |
| YNF Ltd | Health & social care | 2022 |
| Yoga at Juice Limited | Arts & recreation | 2022 |
| YOU & Yours Photography Ltd | Professional & scientific | 2025 |
| Youdix Ltd | Hospitality | 2023 |
| Younas Finance Consultancy Ltd | Information & communication | 2019 |
| Young & Powell Group Ltd | Financial services | 2026 |
| Yucoo Limited | Wholesale & retail | 2004 |
| Zafo Assets Limited | Professional & scientific | 2012 |
| Zamman Ltd | Professional & scientific | 2020 |
| Zanely Dental Ltd | Health & social care | 2025 |
| Zanely Properties Ltd | Real estate | 2025 |
| Zanely Services Limited | Administrative & support | 2026 |
| Zarron Limited | Other services | 2013 |
| Zasa Consulting Ltd | Information & communication | 2025 |
| Zeal GIN Limited | Manufacturing | 2020 |
| Zeal Projects Limited | Administrative & support | 2012 |
| Zeltron Limited | Manufacturing | 2021 |
| Zenith Ventures Limited | Professional & scientific | 2017 |
| Zero Force Ltd | Wholesale & retail | 2025 |
| Zest Solutions Ltd | Administrative & support | 2008 |
| Zippa Industries Ltd | Manufacturing | 2026 |
| Zirkon Group Ltd | Professional & scientific | 2018 |
| Zirkon Ltd | Administrative & support | 2012 |
| Zoab Ltd | Wholesale & retail | 2024 |
| Zoox Labs Ltd | Professional & scientific | 2019 |
| Zrsj Company | Professional & scientific | 2017 |
| Zulfiqar ALI BL Ltd | Other services | 2024 |
| Zushi Bar Limited | Hospitality | 2024 |
| Zushi Station Ltd | Hospitality | 2025 |