| Westwoods Lettings Limited | Real estate | 2006 |
| Wheelers of Uckfield Limited | Transport & logistics | 1990 |
| White Rock Hotels Limited | Administrative & support | 1997 |
| White-Thomson Publishing Limited | Administrative & support | 1999 |
| Whiteline Manufacturing Limited | Manufacturing | 1991 |
| Whitton Harrow Limited | Professional & scientific | 2003 |
| Whitton Marine Limited | Administrative & support | 2004 |
| Whyte Bikes Limited | Wholesale & retail | 1987 |
| Wightman & Parrish Limited | Wholesale & retail | 1915 |
| Wilbury Grove Limited | Administrative & support | 1997 |
| Wild Cherry Limited | Wholesale & retail | 2005 |
| Williams Contractors (Southern) Limited | Construction | 2003 |
| Willow Music Limited | Arts & recreation | 2004 |
| Willowandflint Limited | Wholesale & retail | 2017 |
| Wilson Sandford Limited | Professional & scientific | 2007 |
| Wilson Special Products Limited | Manufacturing | 2002 |
| Wilton Court Flat Management Company (Bexhill) Limited(The) | Households | 1977 |
| Wilton House Investments Limited | Real estate | 1998 |
| Windlelm Limited | Arts & recreation | 1986 |
| Windlesham Services Limited | Health & social care | 2010 |
| Windmill Construction Management Limited | Construction | 1998 |
| Window and Building Services Ltd. | Construction | 2012 |
| Winfield Gears (UK) LLP | | 2006 |
| Winfield Gears Limited | Manufacturing | 1991 |
| Winning Business Solutions Ltd | Other services | 2017 |
| Winton Residents Association Limited | Households | 1989 |
| Wiseacre Corporation Limited | Extraterritorial | 2000 |
| Wiseville & Company Limited | Arts & recreation | 2002 |
| Woodhouse Farm (Sussex) Limited | Agriculture & fishing | 2003 |
| Woodman Projects Limited | Real estate | 1986 |
| Woodrich Designs Limited | Water & waste | 2001 |
| Woodsgate Park Management (Bexhill) Limited | Households | 1989 |
| Woodstock Fires Limited | Wholesale & retail | 1994 |
| Wootten Consultants Limited | Professional & scientific | 2005 |
| Wordsworth Limited | Administrative & support | 2001 |
| Workingabroad Limited | Information & communication | 2001 |
| Workingabroad Projects Limited | Information & communication | 2002 |
| WPS (South East) Limited | Information & communication | 1991 |
| Xana Designs Ltd | Professional & scientific | 2024 |
| Xgnt Limited | Information & communication | 2021 |
| XJR Enterprises Limited | Construction | 2003 |
| XL Lifts Limited | Construction | 2004 |
| Xpedent UK Ltd | Wholesale & retail | 2007 |
| Xpediency UK Limited | Wholesale & retail | 2007 |
| Y.C.E. Agencies Limited | Professional & scientific | 1967 |
| Yellowduck Design Limited | Information & communication | 2003 |
| Yesterday's World Limited | Arts & recreation | 2004 |
| Yewdelve Limited | | 1981 |
| Yorkist Limited | Professional & scientific | 1989 |
| Yoshi Enterprises Limited | Health & social care | 2018 |
| Young Technical Services Limited | Professional & scientific | 1994 |
| Your Cafe & Bakery Ltd | Hospitality | 2020 |
| Your Fitted Home Ltd. | Construction | 2014 |
| Yummy Noodle Bar Limited | Hospitality | 2002 |
| Yundt Ltd | Wholesale & retail | 2025 |
| Z Rooms Ltd. | Hospitality | 1999 |
| Zanlia Limited | Administrative & support | 1999 |
| Zarhel Ltd | Hospitality | 2013 |
| Zatex Limited | Professional & scientific | 2004 |
| ZCO Development Ltd | Professional & scientific | 2025 |
| Zeki Interiors Limited | Construction | 2008 |
| Zelda N00BCO1 Ltd | Financial services | 2025 |
| ZEN Bearings UK Limited | Wholesale & retail | 1996 |
| Zenitel GB Ltd | Manufacturing | 2007 |
| Zioncomfort Homes Limited | Hospitality | 2025 |
| Zipaddress SHH Limited | Real estate | 1998 |
| Zone EC Limited | Construction | 1998 |
| Zunoma Limited | Manufacturing | 1939 |