| Wheldon's Fruit Farm Limited | Agriculture & fishing | 2007 |
| Whiskerflarejewels Ltd | Wholesale & retail | 2025 |
| Whiskertideart Ltd | Wholesale & retail | 2025 |
| Whiskerwispdecor Ltd | Wholesale & retail | 2025 |
| Whiteacre Property Holdings Limited | Real estate | 2024 |
| Whitehouse Apartments Freehold Limited | Households | 2002 |
| Whitings Garage Limited | Wholesale & retail | 2003 |
| Whittaker Property Group (NE) Limited | Real estate | 2023 |
| Wholesum Tech Ltd | Information & communication | 2023 |
| Wild Grace Media Ltd | Information & communication | 2023 |
| Wild Thing Toys (UK) Limited | Other services | 2007 |
| Willow CI Holdings Ltd | Construction | 2024 |
| Willow Staithe Limited | Real estate | 1964 |
| Willow Stonecraft Limited | Manufacturing | 2004 |
| Wilsame Group LP | | 2021 |
| Wine and Gift Ltd | Wholesale & retail | 2013 |
| Wingate Corporate Services Ltd | Hospitality | 2014 |
| Winner (U.K.) Int'L Trading Co., Ltd | Extraterritorial | 2014 |
| Winwick Bark Ltd | Administrative & support | 2024 |
| Wisdom Limited | Professional & scientific | 1996 |
| Wisdom Pension Trustees Limited | Professional & scientific | 1996 |
| Wisdom Tooth Limited | Real estate | 2004 |
| Wisdom Toothbrushes Limited | Wholesale & retail | 1993 |
| With Jacq Ltd | Information & communication | 2026 |
| Witton Chemical Co.Limited | Manufacturing | 1962 |
| WM. Denny & SON Limited | Wholesale & retail | 1950 |
| Wnode Ltd | Information & communication | 2025 |
| Wongs 2019 Ltd | Hospitality | 2019 |
| Woodbridge Estate & Land Limited | Real estate | 2003 |
| Woodbridge Physiotherapy Practice Limited | Health & social care | 2002 |
| Woodbridge School Enterprises Limited | Hospitality | 1990 |
| Woodleyside Information Technology Limited | Information & communication | 1998 |
| Woodstock Accountancy Services Limited | Professional & scientific | 2005 |
| Woofgleamresin Ltd | Wholesale & retail | 2025 |
| Woolnough Contractors Ltd | Construction | 2007 |
| Worksafe Training & Consultancy Ltd | Education | 2007 |
| Worlingham Motor Company Limited | Wholesale & retail | 2003 |
| Wrad Healthcare Consulting Ltd | Health & social care | 2022 |
| Wrightpart Limited | Wholesale & retail | 1977 |
| Wyken Farm Partnership | | 1992 |
| X Aesthetics and Beauty Ltd | Other services | 2024 |
| X-Cel Powder Coatings Limited | Manufacturing | 2001 |
| Xeric Investments Limited | Extraterritorial | 2007 |
| Xyuk Holding Ltd | Financial services | 2026 |
| Yaay Yaay 38 Limited | Hospitality | 2025 |
| Yatu Hub Ltd | Extraterritorial | 2023 |
| YES Property Assets Ltd | Real estate | 2023 |
| YES SIR Ltd | Hospitality | 2025 |
| YES Stays Ltd | Hospitality | 2023 |
| Yeung WAH Limited | Wholesale & retail | 2017 |
| YEW Tree Fields Limited | Agriculture & fishing | 2021 |
| Yinglun Chuanghui Limited | Wholesale & retail | 2025 |
| Yiwu Luliya Trading Co., Limited | Extraterritorial | 2023 |
| York Terrace Mistley (Management) Limited | Real estate | 2003 |
| YOU Bite Ltd | Information & communication | 2018 |
| Young Digital Limited | Professional & scientific | 2023 |
| Young People Taking Action | Other services | 2003 |
| Your Mental Gym Guide Limited | Other services | 2025 |
| Your Property Solutions Limited | Real estate | 2006 |
| Yrnails Ltd | Wholesale & retail | 2013 |
| Yuanzhou International Co., Ltd | Wholesale & retail | 2018 |
| Z Spars International Limited | Manufacturing | 1979 |
| ZA Car Sales Ltd | Wholesale & retail | 2020 |
| Zak's Home Renovations Ltd | Construction | 2023 |
| Zaro Properties Ltd | Real estate | 2023 |
| Zenith Consulting Associates Limited | Extraterritorial | 1989 |
| Zeus Brickwork & Construction Ltd | Construction | 2023 |
| Zhejiang New Day International Trade Co., Limited | Wholesale & retail | 2023 |
| Zhoushan Baihe World Shipping Supply Co., Ltd | Extraterritorial | 2015 |
| Zhuohui International Trade Co., Ltd | Wholesale & retail | 2022 |
| ZNK Limited | Hospitality | 2016 |
| Zolutions Consulting Limited | Professional & scientific | 2019 |
| Zorli Ltd | Health & social care | 2022 |
| Zyme Limited | Information & communication | 2017 |