| West & COE Limited | Other services | 1982 |
| West Lodge Garage Limited | Wholesale & retail | 1976 |
| West Mersea Marine Engineering Limited | Manufacturing | 1995 |
| West-Tex Trading Partnership | | 2000 |
| Westash Holdings Limited | Real estate | 2024 |
| Westbrig Associates Limited | Professional & scientific | 1989 |
| Westcliff Lodge Limited | Health & social care | 1977 |
| Westcliffe Business Services Limited | Administrative & support | 2002 |
| Westco Fabrications (Romford) Limited | | 1988 |
| Westdale Estates Limited | Real estate | 2004 |
| Westdean Consultants Limited | Professional & scientific | 1988 |
| Westdeeb Limited | Agriculture & fishing | 2025 |
| Westech Consultants Limited | Construction | 1996 |
| Western Consult Limited | Information & communication | 2011 |
| Westfield Property Developments Limited | Construction | 2007 |
| Westhill Distribution Limited | Transport & logistics | 2004 |
| Westlake Estates Limited | Hospitality | 1998 |
| Westminster Car Hire Limited | Administrative & support | 1986 |
| Westminster Court (Colchester) Management Company Limited | Households | 1994 |
| Weston Partnership Limited | Professional & scientific | 2002 |
| Westway Construction (London) Limited | Construction | 2005 |
| WET 'N' DRY Boardsports Limited | Wholesale & retail | 2005 |
| Wexadigi Ltd | Information & communication | 2025 |
| Whan Property Management LLP | | 2023 |
| Wheeler Plastering Limited | Construction | 2002 |
| White Cat BSL Limited | Professional & scientific | 2019 |
| White Coast Marketing Limited | Wholesale & retail | 2005 |
| White House Mortgages Limited | Financial services | 1997 |
| White Lodge Therapy LLP | | 2026 |
| White Space Productions Limited | Administrative & support | 2001 |
| Whitehat Properties Limited | Real estate | 2023 |
| Whitehead & Day Limited | Other services | 2006 |
| Whitehead Farm Ltd | Agriculture & fishing | 2002 |
| Whiteley & Thornton Limited | Wholesale & retail | 2000 |
| Whitesheep Ltd | Wholesale & retail | 2025 |
| Whitestone Project Management Limited | Construction | 2017 |
| Whitmore Law Ltd | Professional & scientific | 2016 |
| Whizzkids UK Limited | Education | 2001 |
| Wholistic Wellness Limited | Health & social care | 2019 |
| Wickham Garage Ltd. | Wholesale & retail | 1995 |
| Widdington Recycling Ltd | Water & waste | 2018 |
| Wide Choice Promotions Limited | Professional & scientific | 1990 |
| Widewalk Developments Holdings Limited | Real estate | 2021 |
| Widewalk Developments Limited | Real estate | 1994 |
| Wieretz Ltd | Real estate | 2023 |
| Wigmore Sports Limited | Wholesale & retail | 1982 |
| Wilder Otter Limited | Other services | 2025 |
| Willbe Web Design Limited | Information & communication | 1999 |
| Willem HR Ltd | Administrative & support | 2006 |
| William Allison (Farms) Limited | Agriculture & fishing | 1953 |
| William IVY Data Security & Governance Ltd | Hospitality | 2021 |
| William Taylor Aviation Limited | Transport & logistics | 2006 |
| William Taylor Insurance Services Limited | Financial services | 2007 |
| William Taylor Properties Limited | Real estate | 2005 |
| Willow Hempstead Ltd | Health & social care | 2026 |
| Willow Properties Anglia Ltd | Real estate | 2026 |
| Willow Tree Park Management Company Limited | Households | 2013 |
| Willoww Ltd | Information & communication | 2025 |
| Wills Inc Ltd | Wholesale & retail | 2024 |
| Wilmott Chidley Ltd | Professional & scientific | 2025 |
| Wilshers Consultancy Limited | Professional & scientific | 2003 |
| Wilson Cloud Ltd | Information & communication | 2023 |
| Wilson James Logistics Limited | Construction | 2025 |
| Wilson Machinery International Limited | Wholesale & retail | 1995 |
| Wilson's Essentials Limited | Wholesale & retail | 2026 |
| Wiltonworld Limited | Construction | 1997 |
| Winch's Investments Limited | Real estate | 1943 |
| Windmill (Melnitsa) Limited | Hospitality | 2014 |
| Windsmill Limited | Construction | 1946 |
| Wing Sing Trading Limited | Wholesale & retail | 2023 |
| Winlex Consulting Ltd | Information & communication | 1998 |
| Winsome Marketplace Limited | Wholesale & retail | 2024 |
| Winyard and Co. Builders Merchants Limited | Transport & logistics | 1990 |
| Wipers International Ltd | Professional & scientific | 1991 |
| Wirepoint Systems & Data Limited | Professional & scientific | 2004 |
| Wires Plus Limited | Construction | 1997 |
| Wise Business Solutions Ltd | Manufacturing | 2024 |
| Wispa Ventures Limited | Real estate | 2024 |
| Wisteria Sales Limited | Wholesale & retail | 2005 |
| Witham Estates (2000) Limited | Real estate | 1982 |
| Witham Plant Hire (Rivenhall) Limited | Transport & logistics | 1971 |
| Witlet Limited | Real estate | 2007 |
| Wivenhoe House Hotel Limited | Hospitality | 2009 |
| WJ Mechanical Services Limited | Construction | 2007 |
| WK Hair Ltd | Manufacturing | 2025 |
| Woges INT. Estate & Properties Ltd | Real estate | 2025 |
| WOK U Like (2017) Ltd | Hospitality | 2017 |
| Wollstonecroft Social Vision Limited | Information & communication | 2022 |
| Women of Success CIC | Health & social care | 2024 |
| Wonder World Ltd | Wholesale & retail | 2012 |
| Wonderlease Limited | Real estate | 1990 |
| Wongi Design Technology Limited | Information & communication | 2007 |
| Wood International Agency Limited | Manufacturing | 1984 |
| Wood Lands (Hutton Mount) Limited | Construction | 1963 |
| Woodford Dental Care Ltd | Health & social care | 2026 |
| Woodford Medical Limited | Health & social care | 2002 |
| Woodlands (Colchester) Limited | Health & social care | 1999 |
| Woodlands Schools Enterprises Limited | Education | 2007 |
| Woodlands Total Care Nursing Home Limited | Health & social care | 1991 |
| Woods Workshop Limited | Manufacturing | 2020 |