| Wine Dark Sea Research Limited | Professional & scientific | 2024 |
| Winnipeg Project Ltd | Education | 2026 |
| Wireline Limited | Professional & scientific | 2021 |
| Witching Hour Beauty Limited | Other services | 2024 |
| WM. C. Reade of Aldeburgh Limited | Professional & scientific | 1948 |
| Wolseley Business Park Limited | Administrative & support | 2010 |
| Wolseley Homes Limited | Real estate | 2009 |
| Wood CAL Ltd | Extraterritorial | 2020 |
| Wood CAL Properties Ltd | Real estate | 2025 |
| Woodbridge Lodge Holdings Ltd | Financial services | 2015 |
| Woodbridge Lodge Limited | Health & social care | 2001 |
| Woodfield Child Care Limited | Administrative & support | 2024 |
| Woodlands Day Care Nursery Limited | Education | 2015 |
| World of Fish Limited | Wholesale & retail | 2019 |
| Worlingham Property Co. Limited (the) | Real estate | 1967 |
| Worlingham Property Investments Limited | Administrative & support | 2006 |
| Worton Properties Limited | Real estate | 2018 |
| Wright on Site Limited | Professional & scientific | 2012 |
| WRT Holdings Limited | Financial services | 2023 |
| Wyre Micro Development Limited | Manufacturing | 2018 |
| Xcel Beauty Limited | Other services | 2023 |
| Xist VR Ltd | Information & communication | 2018 |
| Xleys Investments Limited | Financial services | 2019 |
| Xtra Xtra Ltd | Wholesale & retail | 2023 |
| Y&S Fish and Chips Limited | Hospitality | 2023 |
| Yarco Cars and Vehicles Ltd | Wholesale & retail | 2022 |
| Yarco Property Solutions Ltd | Real estate | 2024 |
| YARDBIRD1 Ltd | Hospitality | 2024 |
| Yates & Stroud Utilities Ltd | Construction | 2022 |
| Yazmin Caterers Limited | Hospitality | 2012 |
| YEDI77 Ltd | Extraterritorial | 2013 |
| Yeltel Limited | Professional & scientific | 2021 |
| York 247 Limited | Arts & recreation | 2021 |
| Your Financial Solutions Limited | Financial services | 2015 |
| Your Mortgage Solutions (Lowestoft) Ltd | Financial services | 2005 |
| Your Mortgage Solutions Limited | Financial services | 2014 |
| Your Protection Solutions Limited | Financial services | 2018 |
| Your Safari Limited | Administrative & support | 2008 |
| Your Transporter Haulage & Logistics Ltd | Transport & logistics | 2025 |
| Your-It-Solutions Ltd | Information & communication | 2025 |
| Yourrecruitment Ltd | Administrative & support | 2026 |
| Yourturnaround Limited | Financial services | 2014 |
| Yuki Commercial Limited | Real estate | 2020 |
| Zahra Catering Limited | Hospitality | 2010 |
| Zaman Cars Ltd | Wholesale & retail | 2024 |
| Zami Communities Limited | Information & communication | 2022 |
| Zara Cleaning Ltd | Administrative & support | 2026 |
| Zaza Lofts Limited | Hospitality | 2025 |
| ZEB Soanes Limited | Information & communication | 2022 |
| Zeemarine Limited | Agriculture & fishing | 2024 |
| Zenith Buildings Limited | Construction | 2025 |
| Zenith Renewables Limited | Construction | 2026 |
| Zenith Trade Windows Limited | Construction | 2024 |
| Zenith Windows Limited | Construction | 2021 |
| Zippio Limited | Information & communication | 2025 |
| ZJ Digital Ltd | Professional & scientific | 2025 |
| ZLC Services Ltd | Construction | 2026 |
| ZM Facilities Ltd | Education | 2023 |
| Zonitise Limited | Wholesale & retail | 2020 |
| Zoom Taxis Ltd | Transport & logistics | 2019 |