| Woody's Fast Food Farnborough Limited | Hospitality | 2019 |
| Woolwurth UK Ltd | Real estate | 2020 |
| Work Epic Design Limited | Information & communication | 2022 |
| Work Force (UK) Limited | Wholesale & retail | 1988 |
| WORK2GETHER Limited | Information & communication | 2014 |
| WORK4S Limited | Construction | 2017 |
| World Beauty Aesthetics Ltd | Other services | 2022 |
| World Investment Limited | Real estate | 2025 |
| World Reach Education Limited | Education | 2026 |
| Worldly Angel Ltd | Health & social care | 2013 |
| Worldtrip Ltd | Administrative & support | 2024 |
| Worldwide Trading & Contracting Services Limited | Other services | 2018 |
| Worthyglobal Ltd | Wholesale & retail | 2019 |
| Wrenova Ltd | Wholesale & retail | 2024 |
| WSC Global Limited | Real estate | 2021 |
| WV Capital Limited | Real estate | 2021 |
| Wycombe Corner Shop Ltd | Wholesale & retail | 2025 |
| X-Pert Care Solution Ltd | Administrative & support | 2019 |
| X2VS Ltd | Health & social care | 2024 |
| Xaliye Ltd | Professional & scientific | 2026 |
| Xcel Accounting & Payroll Ltd | Professional & scientific | 2025 |
| Xero Properties Limited | Real estate | 2021 |
| XNC Logistics Ltd | Transport & logistics | 2026 |
| Xoier Ltd | Information & communication | 2025 |
| Xordage DDL Limited | Transport & logistics | 2025 |
| Xpert Automotive Southall Ltd | Wholesale & retail | 2025 |
| Xpress Logistics Services Ltd | Transport & logistics | 2025 |
| Xpressigo Ltd. | Transport & logistics | 2025 |
| Xvpxenos Ltd | Construction | 2024 |
| Xymbolic Properties LLP | | 2018 |
| Y&S Beauty LAB Ltd | Other services | 2017 |
| Y-Dap Ltd | Administrative & support | 2019 |
| Y2 Education | Education | 2014 |
| YA Management Services Ltd | Water & waste | 2023 |
| YA Taiba Travel Ltd | Administrative & support | 2025 |
| Yaaduna London Ltd | Manufacturing | 2023 |
| YAC Cleaning Ltd | Administrative & support | 2024 |
| YAD Contruction Limited | Construction | 2025 |
| Yaqoot Ltd | Wholesale & retail | 2025 |
| Yaremo Ltd | Financial services | 2026 |
| Yash Builders Limited | Construction | 2009 |
| Yashvi Ltd | Wholesale & retail | 2021 |
| Yashwanti Limited | Wholesale & retail | 2022 |
| YAY Goods! Ltd | Wholesale & retail | 2025 |
| Yeading Investments Limited | Real estate | 2024 |
| Yega Ltd | Administrative & support | 2024 |
| Yellow Butterfly Nursery at Allenby Primary School Ltd | Health & social care | 2025 |
| Yellow Butterfly Nursery at Springwell Primary School Ltd | Health & social care | 2026 |
| Yellow Butterfly Nursery in Osterley Ltd | Health & social care | 2024 |
| Yellow Butterfly Nursery Ltd | Health & social care | 2019 |
| Yellow LINE13 Ltd | Construction | 2025 |
| Yeoil Investments Ltd | Real estate | 2024 |
| Yesido Global Limited | Wholesale & retail | 2025 |
| Yesido UK Ltd | Wholesale & retail | 2022 |
| Yesplus UK Ltd | Wholesale & retail | 2022 |
| Yettos Ltd | Administrative & support | 2022 |
| YGQ Accountants & Advisors Limited | Professional & scientific | 2023 |
| YHH Global Ltd | Wholesale & retail | 2026 |
| Your Corner Shop Ltd | Wholesale & retail | 2025 |
| Your Little Gift Shop Limited | Wholesale & retail | 2011 |
| Your Local Superstore Ltd | Wholesale & retail | 2019 |
| Your One Wish | Health & social care | 2015 |
| Youthful Trees Limited | Manufacturing | 2024 |
| YPI (UK) Ltd. | Wholesale & retail | 2013 |
| YS Elite Ltd | Wholesale & retail | 2024 |
| YUI HUI Logistics Ltd | Transport & logistics | 2023 |
| Yukti Investment Ltd | Real estate | 2022 |
| Yummy Mummy Snacks Limited | Wholesale & retail | 2025 |
| Yurika Limited | Wholesale & retail | 2025 |
| Yuvi Construction Ltd | Construction | 2020 |
| Yuvraj Builders Limited | Construction | 2026 |
| Yuvraj Construction Limited | Construction | 2019 |
| Yuvraj Contractors Ltd | Construction | 2019 |
| Yuvraj International Ltd | Wholesale & retail | 2022 |
| Z & H Distribution Ltd | Wholesale & retail | 2003 |
| Z Y Zhou Export Limited | Wholesale & retail | 2025 |
| Z&F Associate Company Limited | Administrative & support | 2024 |
| Z&M Business Ltd | Administrative & support | 2024 |
| Z&S Auto Ltd | Wholesale & retail | 2025 |
| Z&S Construction Property Services Ltd | Construction | 2022 |
| Zabardast Butterflies Welfare Ltd | Health & social care | 2020 |
| Zacla Ltd | Professional & scientific | 2018 |
| Zafar Jewellers Ltd | Manufacturing | 2020 |
| Zafiro Azul Limited | Administrative & support | 2023 |
| Zahid Foods Limited | Wholesale & retail | 2020 |
| Zain Tradings Ltd | Other services | 2017 |
| Zaire Blue Ltd | Real estate | 2018 |
| Zamtalk Communication Ltd | Information & communication | 2019 |
| Zara Maia Investments Limited | Real estate | 2018 |
| Zareon Services Limited | Administrative & support | 2024 |
| Zarnaga Trading Ltd | Transport & logistics | 2020 |
| Zastavna Ltd | Construction | 2023 |
| Zavento Ltd | Wholesale & retail | 2025 |
| Zavv Limited | Households | 2021 |
| Zayaan Corporation Limited | Real estate | 2022 |
| Zaza Technologies Ltd | Wholesale & retail | 2023 |
| ZED Primo Freight Service Ltd | Transport & logistics | 2023 |
| ZEE Auto Mods Ltd | Wholesale & retail | 2025 |
| ZEE Cabs Ltd | Transport & logistics | 2019 |
| ZEE Tours Ltd | Administrative & support | 2025 |