| Wheatley Property Holdings Ltd | Real estate | 2020 |
| White Night London Ltd | Health & social care | 2020 |
| Whitfield Property & Construction Support Consultancy Limited | Construction | 2021 |
| WI Communications Ltd | Information & communication | 2016 |
| Wild Harbour Ltd | Professional & scientific | 2020 |
| Wilder and Kind Limited | Information & communication | 2024 |
| Wilkins Caldeira Capital Ltd | Real estate | 2022 |
| Wilkins Capital Group Ltd | Financial services | 2025 |
| Will Custodian Limited | Other services | 2004 |
| Willow Olive Holdings Ltd | Real estate | 2019 |
| Wilmshurst Ltd | Wholesale & retail | 2014 |
| Wincell Limited | Wholesale & retail | 2025 |
| Wise Consultancy Services Limited | Professional & scientific | 2014 |
| Witney Imaging Ltd | Professional & scientific | 2025 |
| Wizzkids UK Ltd | Wholesale & retail | 2025 |
| Woodbury Home Services Ltd | Construction | 2023 |
| Woodford Owen Consulting Limited | Professional & scientific | 2017 |
| Woodrich Ltd | Real estate | 2017 |
| Working EYE Limited | Other services | 2009 |
| Working EYE Productions Ltd | Arts & recreation | 2018 |
| World Scout Shop Limited | Wholesale & retail | 2011 |
| Worthing Scaffolding Ltd | Construction | 2013 |
| Wyrmhero Limited | Information & communication | 2024 |
| Wyvern Organ Builders Limited | Real estate | 1966 |
| Xavier GAS Installations Ltd | Construction | 2022 |
| XC Security Services Limited | Real estate | 2003 |
| Yacht Services Global Limited | Wholesale & retail | 2020 |
| Yagoub Holdings Ltd | Financial services | 2024 |
| Yasemin House Ltd | Health & social care | 2025 |
| Yawuzo Ltd | Extraterritorial | 2022 |
| Your Home Mobility Solutions Ltd | Construction | 2019 |
| Your MAN Handyman Ltd | Households | 2019 |
| Your Nutritional Blueprint Ltd | Health & social care | 2018 |
| Your Sweet Dreams Limited | Wholesale & retail | 2024 |
| Z P T Limited | Construction | 2023 |
| Zaft Property Ltd | Real estate | 2024 |
| Zero Double X Publishing Limited | Information & communication | 2002 |
| Ziana London Ltd | Wholesale & retail | 2026 |
| Zidicon Limited | Information & communication | 2013 |
| Zone Store Limited | Wholesale & retail | 2026 |
| Zouk by Sea Ltd | Hospitality | 2025 |