| West in Ltd | Construction | 2026 |
| Westbury Solutions Limited | Energy | 2015 |
| Westcliff T and D Ltd | Construction | 2025 |
| Westlake Enterprises Ltd | Real estate | 2024 |
| Wests SM Motors Ltd | Wholesale & retail | 2022 |
| WH Procraft (London-Uk) Limited | Wholesale & retail | 2025 |
| What CAN I DO to Help YOU Ltd | Administrative & support | 2017 |
| Wheelie Skate Academy Ltd | Other services | 2026 |
| Whemen Limited | Wholesale & retail | 2024 |
| White Eagle Cars Ltd | Extraterritorial | 2016 |
| White Eagle Group Ltd | Transport & logistics | 2017 |
| White Eagle Polish Community CIC | Information & communication | 2024 |
| Whitehub Ltd | Transport & logistics | 2018 |
| Whiteleys Limited | Construction | 2003 |
| Wholesale Desserts Limited | Manufacturing | 2025 |
| Wild Cubs Clothing Ltd | Wholesale & retail | 2025 |
| Wildlife Eden Safaris Ltd | Administrative & support | 2014 |
| William Michie Consultants Ltd | Public administration | 2017 |
| Williams College Ltd | Education | 2019 |
| Williams Van Courier Ltd | Transport & logistics | 2017 |
| Willoughby Property Solution Ltd | Real estate | 2023 |
| Windmill Hill Investment Property Ltd | Real estate | 2015 |
| Windser Road Investments Limited | Households | 2024 |
| Windsor Alarms & Security Systems Ltd | Extraterritorial | 2016 |
| WIZ Transport and Courier Service Limited | Transport & logistics | 2024 |
| Wolex Investment Company Limited | Real estate | 2021 |
| Wolton Limited | Professional & scientific | 2025 |
| Won-Of-One Ltd | Information & communication | 2025 |
| Woodford Haulage Limited | Construction | 2010 |
| Wordgates Limited | Real estate | 2023 |
| Wordlife Assembly Limited | Other services | 2022 |
| Workspro Ltd | Construction | 2024 |
| World Inst of Finance Limited | Education | 2025 |
| World of Online Ltd | Other services | 2020 |
| World Wide Auto UK Ltd | Wholesale & retail | 2021 |
| Wright Engineering (Rainham) Limited | Construction | 1969 |
| WRY Developments Limited | Construction | 1981 |
| Wunba Limited | Health & social care | 2023 |
| Wynnsoft Ltd | Information & communication | 2022 |
| Xair Technologies Ltd | Information & communication | 2023 |
| XR Live Solutions Ltd | Information & communication | 2016 |
| XYZ Geodesy Limited | Construction | 2015 |
| Yaaallah Limited | Wholesale & retail | 2023 |
| Yacim-Jones Ltd | Real estate | 2021 |
| YAG Ltd | Information & communication | 2025 |
| Yahweh Dwells Global Ministries Ltd | Other services | 2022 |
| YAL Healthcare Ltd | Health & social care | 2026 |
| Yardopen Limited | Extraterritorial | 1997 |
| YAS Collectibles Ltd | Wholesale & retail | 2026 |
| Ycodeit Ltd | Information & communication | 2022 |
| YEL Forum Limited | Health & social care | 2014 |
| Yemo Motors Limited | Wholesale & retail | 2017 |
| Yezoh Clothing Ltd | Wholesale & retail | 2025 |
| Yfit Limited | Information & communication | 2024 |
| Yoke Pro Ltd | Information & communication | 2018 |
| Yoma Trading Ltd | Professional & scientific | 2025 |
| Yondu Ltd | Transport & logistics | 2023 |
| Youles Construction Ltd | Construction | 2022 |
| Younis Childminding Ltd | Health & social care | 2023 |
| Younis Foundation Ltd | Construction | 2020 |
| Your Care Nursing Ltd | Health & social care | 2020 |
| Your Furniture Home Ltd | Wholesale & retail | 2026 |
| Your Happy Sleepers Ltd | Health & social care | 2024 |
| Youth and Adult Community Training CIC | Education | 2026 |
| YP Electricians Ltd | Construction | 2017 |
| YS Financial Ltd | Professional & scientific | 2024 |
| Yuac Group Ltd | Professional & scientific | 2026 |
| Z & E Property Development Company Limited | Real estate | 2021 |
| Z Yaremcha Builders Ltd | Construction | 2023 |
| Z&M Composite Ltd | Manufacturing | 2024 |
| Zadan (London) Limited | Financial services | 2023 |
| ZAN Studio Ltd | Professional & scientific | 2024 |
| ZAN UK Barber Ltd | Other services | 2024 |
| Zanda Technology Limited | Information & communication | 2017 |
| Zaraella Limited | Real estate | 2025 |
| Zask Global Management Ltd | Wholesale & retail | 2022 |
| Zatrom Energy Solutions Ltd | Energy | 2025 |
| Zayaan London Limited | Education | 2019 |
| Zeco Design Ltd | Professional & scientific | 2025 |
| ZEE Barber Lounge Limited | Other services | 2024 |
| Zemaske Limited | Public administration | 2019 |
| Zembe Transport Services Ltd | Transport & logistics | 2025 |
| Zenith Tilbury Limited | Real estate | 2023 |
| Zenith Yarmouth Limited | Real estate | 2023 |
| Zerant (UK) Limited | Administrative & support | 2007 |
| Zeytin Catering Services Ltd | Hospitality | 2026 |
| ZHI Support Services Limited | Wholesale & retail | 2021 |
| Ziniukas Ltd | Education | 2023 |
| Zions Hill Global Ltd. | Professional & scientific | 2025 |
| Zitami Ltd | Real estate | 2022 |
| Ziwahb Ltd | Wholesale & retail | 2019 |
| ZM Facility Management Ltd | Administrative & support | 2026 |
| Zmetal Ltd | Manufacturing | 2013 |
| Zmetal Powder Coatings Ltd | Manufacturing | 2019 |
| Zobest Ventures Limited | Information & communication | 2023 |
| Zoli & SON Joinery Ltd | Construction | 2023 |
| ZOM Aesthetics Academy CIC | Education | 2025 |
| ZOM Aesthetics Clinic Ltd | Education | 2023 |
| Zong DUO ZHU Limited | Wholesale & retail | 2025 |
| ZS Motors London Ltd | Wholesale & retail | 2021 |