| WH Maint Services Limited | Blackpool | 2024 |
| Wharf Resources Ltd | Surbiton | 2005 |
| Wheal Ellen Mine Holdings Limited | London | 2026 |
| Wheal Jane Services Limited | Truro | 2000 |
| Wheconsult Limited | Wimborne | 2018 |
| Wheeler Industrial Worldwide Limited | Winchester | 2015 |
| Whim Peat Limited | Scottish Borders | 2017 |
| Whimpy Solid Mineral Resources Marketing Ltd | Hull | 2022 |
| Whitby Sea Salt Ltd | Colne | 2019 |
| White Flame Energy Ltd | London | 2013 |
| White Water Gold Ltd | London | 2025 |
| Whitehall Stone Sales Limited | Bradford | 1995 |
| Whitemountain Quarries Ltd | Newtownabbey | 1985 |
| Whiteshore Sea Salt Ltd | Isle Of North Uist | 2018 |
| Whits Ltd | Great Yarmouth | 2023 |
| Whittimere Quarry Ltd | Church Stretton | 2018 |
| WHR Subsea Inspection Services Limited | Southsea | 2014 |
| Whsubsurface Limited | Hook | 2026 |
| WHT Asbestos Limited | Hull | 2020 |
| Widdyfields Limited | Whitby | 2014 |
| Wight Building Materials Ltd | Coalville | 2013 |
| Wigley Consulting Services Ltd | London | 2025 |
| Wigsley Sand & Gravel Limited | Market Rasen | 2022 |
| Wil-Drill Limited | Ellon | 2007 |
| Wildcat Gold PLC | Uxbridge | 2020 |
| Wildmoor Quarry Products Limited | Shropshire | 2003 |
| Wileman Engineers Limited | Ashby De La Zouch | 1964 |
| Wilgolz Ltd | Telford | 2013 |
| Wilkes Site Services Limited | Merthyr Tydfil | 2024 |
| Wilkinson Coating Inspector Ltd | South Shields | 2015 |
| William Clark (Barry) Limited | Carnoustie | 2010 |
| William George Sand & Gravel Limited | King'S Lynn | 2017 |
| William Jacobson Ltd | Chester Le Street | 2021 |
| William Thompson & SON (Dumbarton) Limited | | 1947 |
| Williams Petrophysics Limited | Llandudno | 2026 |
| Williamson Aggregates Ltd | Paisley | 2025 |
| Willmax Design Services Ltd | London | 2020 |
| Willowburn North Limited | Turriff | 2014 |
| Willowcroft Aggregates Ltd | Wisbech | 2018 |
| Willthrillexports Ltd | London | 2025 |
| Wilsher Inspection Ltd | Stockton-On-Tees | 2018 |
| Wilson Global Projects Limited | Montrose | 2008 |
| Wilson Services Nflk Ltd | King'S Lynn | 2024 |
| Winchester Group Holdings Limited | Basingstoke | 2011 |
| Winchester Procurement Limited | Basingstoke | 1990 |
| Windsmere Stone & Granite Ltd | Melksham | 2002 |
| Windward Exploration & Properties Limited | Wallingford | 2003 |
| Windy MAC Ltd | Chester Le Street | 2023 |
| Windyhollows PLC | London | 2020 |
| Winital International Ltd | London | 2016 |
| Winjet Construction Ltd. | London | 2020 |
| Winscombe Engineering Ltd | Winscombe | 2007 |
| Winterbourne Minerals Limited | Canterbury | 2007 |
| Winterfields Group Ltd | Southend-On-Sea | 2018 |
| Winterfields Resources UK Ltd | London | 2025 |
| Wise Bull Ltd | London | 2017 |
| Wise Mining Solutions Ltd | London | 2025 |
| Witwatersberg Consolidated Mining Group Ltd | Cardiff | 2022 |
| WJM International (UK) Ltd | Mildenhall | 2012 |
| WKH Aggregates (NE) Ltd | Hetton-Le-Hole | 2024 |
| WMC Services Ltd | Glasgow | 2026 |
| Wmcc Instrument Fitting Limited | Greenock | 2016 |
| WMM Solutions Limited | Ellon | 2015 |
| WMR Consulting Ltd | Brechin | 2022 |
| WMR Ltd | Blackpool | 2014 |
| WNR Subsea Controls Ltd | Montrose | 2006 |
| Wolf Minerals (UK) Limited | Manchester | 2007 |
| Wolfseason Limited | West Midlands, England, | 2018 |
| Wolves Group International (WGI) Limited | London | 2025 |
| Womg Ltd | Gillingham | 2023 |
| Wood (Indonesia) Limited | Aberdeen | 2021 |
| Wood Group Production Services UK Limited | Aberdeen | 2005 |
| Wood Group UK Limited | Aberdeen | 2006 |
| Wood Mackenzie Limited | Edinburgh | 2001 |
| Wood Production Services Ltd | Montrose | 2006 |
| Wood Subsurface Ltd | Ipswich | 2024 |
| Woodbine Crew Limited | Liverpool | 2018 |
| Woodside Energy (Bimshire) Limited | London | 2013 |
| Woodside Energy (Bulgaria) Limited | London | 2018 |
| Woodside Energy (Carlisle Bay) Limited | London | 2013 |
| Woodside Energy (Congo) Limited | London | 2019 |
| Woodside Energy (Egypt) Limited | London | 2013 |
| Woodside Energy (Great Britain) Limited | London | 1972 |
| Woodside Energy (LA) Marketing Ltd | London | 2017 |
| Woodside Energy (LA) Trading UK Ltd. | London | 2017 |
| Woodside Energy (LA) UK Ltd | London | 2016 |
| Woodside Energy (Mexico) Limited | London | 2014 |
| Woodside Energy (Namibia) Limited | London | 2013 |
| Woodside Energy (Trinidad Block 14) Limited | London | 2013 |
| Woodside Energy (Trinidad Block 23A) Limited | London | 2013 |
| Woodside Energy (Trinidad Block 23B) Limited | London | 2013 |
| Woodside Energy (Trinidad Block 28) Limited | London | 2013 |
| Woodside Energy (Trinidad Block 29) Limited | London | 2013 |
| Woodside Energy (Trinidad Block 3) Limited | London | 2014 |
| Woodside Energy (Trinidad Block 5) Limited | London | 2013 |
| Woodside Energy (Trinidad Block 6) Limited | London | 2013 |
| Woodside Energy (Trinidad Block 7) Limited | London | 2014 |
| Woodside Energy Finance (UK) Limited | London | 2019 |
| Wootton International (UK) Limited | Solihull | 2016 |
| Wopseen (Europe) Crop Nutrition Ltd | Cardiff | 2025 |