| Yoga Enterprise Ltd | Information & communication | 2020 |
| Yogi Darshan Limited | Wholesale & retail | 2020 |
| Yogi Medicare Ltd | Wholesale & retail | 2021 |
| Yoirify Limited | Professional & scientific | 2023 |
| Yole Services Limited | Extraterritorial | 2020 |
| Yonder Power Limited | Construction | 2025 |
| YOP IT Solutions Ltd | Professional & scientific | 2015 |
| Yopet Group Ltd | Wholesale & retail | 2026 |
| Yorkbury Management Limited | Professional & scientific | 1988 |
| Yorkway Catering Limited | Hospitality | 2024 |
| YOU and EYE London Limited | Health & social care | 2011 |
| YOU Buy WE Clean Ltd | Administrative & support | 2022 |
| YOU Matter Care Limited | Health & social care | 2023 |
| Young Mobile Limited | Information & communication | 2015 |
| Young's Estates Limited | Construction | 1983 |
| Youngers Consultancy Ltd | Information & communication | 2014 |
| Your Advantage Tennis Academy Limited | Arts & recreation | 2020 |
| Your Creative Events Company Ltd | Hospitality | 2022 |
| Your Local PUB Company Limited | Hospitality | 2017 |
| Your Services Ltd | Administrative & support | 2019 |
| Your Worktops Ltd | Construction | 2019 |
| Youtube Automations Limited | Wholesale & retail | 2025 |
| YOV Motors Ltd | Transport & logistics | 2020 |
| YP Entertainment Ltd | Information & communication | 2021 |
| Ypfs Holdings Ltd | Financial services | 2025 |
| Yprop Ltd | Real estate | 2024 |
| YT Decor Ltd | Construction | 2015 |
| YT Interiors Ltd | Construction | 2007 |
| Yuanda Limited | Health & social care | 2016 |
| Yugveda AI Solution Limited | Information & communication | 2025 |
| Yulcom AI Ltd | Information & communication | 2026 |
| Yulk Ltd | Construction | 2026 |
| Yumme Ltd | Hospitality | 2025 |
| Yunus & Co Enterprise Ltd | Hospitality | 2023 |
| Yutari Consulting Ltd | Information & communication | 2017 |
| Yutori Tattoo and Arts Limited | Other services | 2024 |
| Yuyigarden Ltd | Hospitality | 2025 |
| Yvetteworld Ltd. | Information & communication | 2015 |
| YZ Sterling Ltd | Real estate | 2025 |
| YZ Worldwide Ltd | Wholesale & retail | 2025 |
| Yzsm Ltd | Professional & scientific | 2022 |
| Z a K Beauty Ltd | Transport & logistics | 2024 |
| Z Soliman Holdings Ltd. | Wholesale & retail | 2025 |
| Z&A Enterprises Ltd | Professional & scientific | 2026 |
| Z&L London Ltd. | Other services | 2015 |
| Z&T Foodie Ltd | Hospitality | 2026 |
| Z&T Global Ltd | Hospitality | 2026 |
| Z-Hayaa Ltd | Professional & scientific | 2023 |
| ZAB & Co Trading Ltd | Wholesale & retail | 2020 |
| Zachstar Ltd | Wholesale & retail | 2025 |
| Zafar Homes Ltd | Real estate | 2025 |
| Zagy Hauliers Limited | Transport & logistics | 2019 |
| Zagy Mobile Homes Ltd | Other services | 2019 |
| Zahk Consultancy Services Limited | Information & communication | 2018 |
| Zain Marketplace Ltd | Wholesale & retail | 2026 |
| ZAK Cleanings Ltd | Administrative & support | 2015 |
| Zakkauk Ltd | Wholesale & retail | 2014 |
| Zamal Limited | Other services | 2018 |
| Zamfi Transport Ltd | Transport & logistics | 2019 |
| ZAN Consultants Limited | Professional & scientific | 2015 |
| Zane Accounting Services Limited | Professional & scientific | 1995 |
| Zane Business Consulting Limited | Information & communication | 2007 |
| Zane Developments Limited | Real estate | 2025 |
| Zantiques Ltd | Wholesale & retail | 2019 |
| Zapata Investments Ltd | Information & communication | 2009 |
| Zaphire Integrated Solutions Limited | Professional & scientific | 2016 |
| Zara Mangal Ltd | Hospitality | 2024 |
| Zarafa Arts Ltd | Arts & recreation | 2020 |
| Zareef Consultancy Ltd | Information & communication | 2023 |
| Zarexor Ltd | Real estate | 2025 |
| Zarqaam Ltd | Wholesale & retail | 2025 |
| Zarza Jewels Ltd | Wholesale & retail | 2025 |
| Zatasa Properties Limited | Real estate | 2026 |
| ZD88 Consulting Ltd | Professional & scientific | 2024 |
| Zdereli Limited | Real estate | 2025 |
| Zeba Hair and Beauty Limited | Other services | 2012 |
| Zednee Limited | Administrative & support | 2013 |
| Zedx Apps Ltd | Information & communication | 2024 |
| ZEE ENG Works Ltd | Professional & scientific | 2025 |
| Zeevo Ltd | Real estate | 2024 |
| Zefaro Holdings Ltd | Financial services | 2025 |
| Zefaro Investments Ltd | Real estate | 2025 |
| Zefi Ltd | Health & social care | 2017 |
| Zelbinion International LP | | 2013 |
| Zelda 23 Ltd | Hospitality | 2023 |
| Zelph Limited | Information & communication | 2024 |
| Zemis Consulting Limited | Professional & scientific | 2021 |
| Zempt Homes Limited | Real estate | 2022 |
| ZEN CSR Ltd | Information & communication | 2020 |
| Zendrake Investments Ltd | Real estate | 2018 |
| Zenith Lodge (Finchley) Management Limited | Real estate | 1973 |
| Zenith Real Estate Holdings Ltd | Real estate | 2024 |
| Zenith Sisters Ltd | Real estate | 2024 |
| Zenithcad UK Limited | Information & communication | 2019 |
| Zenny London Ltd | Wholesale & retail | 2025 |
| Zenvirra Limited | Wholesale & retail | 2026 |
| Zeny Hair Studio Ltd | Other services | 2026 |
| Zeolite Consultancy Services Ltd | Real estate | 2015 |
| Zeopick Limited | Professional & scientific | 2017 |
| Zephyrus Marketing Limited | Information & communication | 2014 |