| Wellhouse Lane Management Company Limited | Households | 2019 |
| Wendorff.Works Ltd | Professional & scientific | 2022 |
| West Sussex Plant Hire Limited | Administrative & support | 2019 |
| WGP (South East) Ltd | Real estate | 2020 |
| Whitby Contracts Limited | Professional & scientific | 2007 |
| Whitelands (Freehold) Limited | Households | 2004 |
| Whitelands Management Company Limited | Households | 1988 |
| Whitewood Events Ltd | Administrative & support | 2026 |
| Wholehearted Marketing Ltd | Administrative & support | 2015 |
| Wickham Heath Limited | Professional & scientific | 2021 |
| Wickwoods Premier Kitchens Limited | Construction | 2025 |
| Wide World Media Limited | Manufacturing | 2010 |
| Wilbert Investments Limited | Financial services | 2023 |
| Wilco Builders Limited | Construction | 2014 |
| Wild Mango Kitchen Ltd | Hospitality | 2023 |
| William Potts Limited | Wholesale & retail | 2003 |
| Willow Aesthetics Ltd | Health & social care | 2015 |
| Willow Electronics UK Limited | Manufacturing | 2004 |
| Willow Tree Property Management Ltd | Households | 2025 |
| Willrose Couriers Ltd | Transport & logistics | 2012 |
| Winckless Consulting Services Limited | Professional & scientific | 2003 |
| Windmill Projects Ltd | Administrative & support | 2009 |
| Wintons Close Management Company Limited | Households | 2008 |
| Wintons Fishery Limited | Agriculture & fishing | 2017 |
| Wintons Fishing Association Limited | Other services | 2002 |
| Wintons Lakes Limited | Hospitality | 2024 |
| Wired Electrics Limited | Construction | 2014 |
| Wiser UK Logistics Ltd | Transport & logistics | 2019 |
| Wiston Interiors Ltd | Wholesale & retail | 2024 |
| WME Promotions Ltd | Extraterritorial | 2017 |
| Wolli Films Limited | Information & communication | 2016 |
| Wolverhampton Inclusive Send Help Ltd | Education | 2026 |
| Wolves Removals Limited | Wholesale & retail | 2016 |
| Womanwell Personal Training Ltd | Arts & recreation | 2023 |
| Wonderma Ltd | Health & social care | 2022 |
| Wood Works Brighton Ltd | Manufacturing | 2012 |
| Woodbury House Freehold Limited | Households | 2010 |
| Woodbury House Management Limited | Households | 2004 |
| Woodland Court Burgess Hill Limited | Households | 2008 |
| Woodlands Office Park Management Limited | Administrative & support | 2008 |
| Woodlands View (Nassau Drive) Management Limited | Households | 2013 |
| Woods Environmental Limited | Construction | 2006 |
| Woodside (Haywards Heath) Management Company Limited | Households | 2014 |
| Woodward Automotive Limited | Wholesale & retail | 2016 |
| Woodward Carpentry & Building Limited | Construction | 2019 |
| Woof Ltd | Other services | 2020 |
| Woolovers Limited | Wholesale & retail | 1997 |
| World Solar Ltd | Construction | 2023 |
| Worlds END Social Ltd | Other services | 2019 |
| Woudman Oakley | | 1998 |
| Wourth Group Limited | Professional & scientific | 2014 |
| WPM Software Limited | Professional & scientific | 2006 |
| WTP Scaffolding Services Ltd | Construction | 2020 |
| Wulff Trading Ltd | Wholesale & retail | 2017 |
| Wylie & Co. Property Consultancy Ltd | Real estate | 2019 |
| Xdma Ltd | Hospitality | 2025 |
| Xtrable Ltd | Information & communication | 2021 |
| Yorr Ltd | Hospitality | 2023 |
| Young's Employment Services Ltd | Administrative & support | 2024 |
| Ypsilon UK Ltd | Information & communication | 2006 |
| ZA Electrical Ltd | Construction | 2013 |
| Zark Investments Ltd | Real estate | 2011 |
| Zeloom Limited | Extraterritorial | 2012 |
| Zero Hub C.I.C. | Wholesale & retail | 2023 |
| Zimy Corporation Ltd | Wholesale & retail | 2024 |
| Zimy Healthcare Ltd | Health & social care | 2024 |
| Zion Residential Limited | Real estate | 2020 |
| Zion Technical Solutions Ltd | Information & communication | 2022 |
| ZOE & Zyana Limited | Real estate | 2025 |
| Zoom Estate Agents Limited | Real estate | 2016 |
| ZOOM995 Ltd | Real estate | 2013 |
| ZR Builders and Property Maintenance Limited | Construction | 2020 |