| Waterfoot Natural Resources Ltd | Belleek | 2024 |
| Waterford Quarries Ltd | London | 2020 |
| Waterway UK Ltd | London | 2008 |
| Wath Quarries Limited | York | 1954 |
| Watling Estates Limited | Leighton Buzzard | 1955 |
| Watt Subsea Services Limited | Fraserburgh | 2008 |
| Watts Blake Bearne and Company Limited | Talke | 1914 |
| Wave Inspections Ltd | Stockton-On-Tees | 2021 |
| Wavecrest Associates Limited | Hampshire | 2002 |
| WAW 888 Ltd | Manchester | 2024 |
| Wayland Copper Ltd | London | 2010 |
| Wayne Fueling Systems UK Holdco Ltd. | Eastleigh | 2014 |
| Wayne Geological Limited | Cardiff | 2002 |
| Wayne Turnbull Limited | South Shields | 2025 |
| WB International Consulting Ltd | London | 2016 |
| WBB Eastern Europe Limited | Talke | 1986 |
| WBB Limited | Beccles | 2021 |
| Wbjsevices Ltd | South Shields | 2024 |
| WD Safety Ltd | Montrose | 2015 |
| WE Industries Holdings Ltd | London | 2024 |
| WE Soda Ltd | London | 2016 |
| Wealden Exploration Limited | Nr Ashford | 1986 |
| Weardale Lithium Limited | Durham | 2018 |
| Weardale Minerals Limited | Yeovil | 2025 |
| Weatherford Eurasia Limited | Loughborough | 1989 |
| Weatherford U.K. Limited | Loughborough | 1965 |
| Weaver Offshore Solutions Ltd | Liverpool | 2014 |
| Wedgwood and Harrison Ltd | Whitby | 2012 |
| Weeks ENG Ltd | Wells | 2019 |
| Weir Group Europe Limited | Stafford | 2026 |
| Weizarde Industrial (UK) Mining Co., Ltd | Cambridge | 2024 |
| Weld-Delux Ltd | Peterhead | 2015 |
| Weld-Tech Services Limited | Ellon | 2000 |
| Welding Integrity Services Limited | Sittingbourne | 2013 |
| Welker UK Ltd | Hastings | 2026 |
| Well Access Ltd. | Aberdeen | 2012 |
| Well Advanced Solutions Ltd | Aberdeen | 2012 |
| Well Decom Limited | Aberdeen | 2016 |
| Well Engineering Consultancy Ltd. | Fraserburgh | 1999 |
| Well Integrity Verification Limited | Stow On The Wold | 2016 |
| Well Intervention Services Limited | Angus | 1998 |
| Well Search Limited | Great Yarmouth | 2006 |
| Well Systems Technology Ltd | Prestwick | 2011 |
| Well Technical Services Limited | Crieff | 2015 |
| Well Technology Consultants Limited | Glasgow | 2001 |
| Well Technology Group Ltd | Dundee | 2023 |
| Wellbore Integrity Solutions UK Limited | London | 2019 |
| Welldecommissioned UK Limited | Banchory | 2021 |
| Weller Offshore Ltd | Great Yarmouth | 2022 |
| Wellesley Holdco Limited | Leeds | 2014 |
| Wellesley Manco Limited | London | 2014 |
| Wellgear Limited | London | 2015 |
| Wellgenix Limited | Norwich | 2022 |
| Wellhead Management Ltd | Hemel Hempstead | 2017 |
| Wellpath Limited | Glasgow | 2017 |
| Wellpro Group Limited | Aberdeen | 2018 |
| Wellred Ltd | Insch | 2007 |
| Wells and Shaw Solutions Limited | Sheffield | 2018 |
| Wellsahead Limited | Glasgow | 2020 |
| Wellservices Ltd | Forfar | 2011 |
| Wellsite Geological Services Ltd | Buckie | 2008 |
| Welltrain Limited | London | 2003 |
| Welltronex Ltd | London | 2023 |
| Welsh Slate Product Ltd | Bangor | 2025 |
| Welton Aggregates Limited | Spilsby | 2003 |
| Wentvalley Aggregates & Recycling Ltd | Droitwich | 2011 |
| Wentworth Resources (UK) Limited | London | 2014 |
| Wessex Fluids Ltd | Broadstone | 2017 |
| Wessex Geoscience Ltd | Salisbury | 2022 |
| West Coast Gold Limited | Glasgow | 2016 |
| West Country Metals Limited | London | 2026 |
| West Cumbria Mining (Holdings) Limited | Sheffield | 2010 |
| West Cumbria Mining Limited | Sheffield | 2010 |
| West Drilling Limited | Glasgow | 2017 |
| West END Drilling Limited | Banchory | 1998 |
| West Grange Solutions Ltd | Perth | 2016 |
| West Norfolk Lime Limited | Kings Lynn | 2009 |
| West of England Quarry Company Limited | Birmingham | 1997 |
| West Polmear Consulting Limited | St. Austell | 2024 |
| Westate Resources Limited | London | 2017 |
| Westbound Capital Limited | London | 2025 |
| Westburne OIL Limited | London | 1971 |
| Westcliffe Works Ltd | Cleckheaton | 2024 |
| Westcountry Minerals Limited | Redruth | 2012 |
| Westdown Plant Ltd | Craigavon | 2004 |
| Westdown Project Ltd. | Falkirk | 2011 |
| Western Europe Chemical Industry Group Ltd | London | 2021 |
| Western Gold Exploration (UK) Limited | London | 2016 |
| Western Light Ltd | London | 2021 |
| Western Rock Aggregates Ltd | Milford Haven | 2019 |
| Western Stone Supplies Ltd | Swansea | 2009 |
| Westerngeco Limited | Crawley | 1978 |
| Westonhill Limited | Hereford | 1994 |
| Westrip Holdings Limited | Sutton Coldfield | 2002 |
| Westsouthern Capital Limited | London | 2019 |
| Westward Developments Ltd | Fraserburgh | 2006 |
| Westwise Holding Group Ltd | Luton | 2025 |
| Wetworx Marine Services Ltd | Barrow-In-Furness | 2022 |
| Wexalia Ltd | Truro | 2021 |
| WGP Group Ltd | Frome | 2017 |