| William Harvey Medical Limited | Southampton | 2011 |
| William Harvie & Co. (Farmers) Limited | Kilmarnock | 1950 |
| William Johnston N.I. Ltd | Saintfield | 2015 |
| William Jones (Farms) Limited | Norwich | 1961 |
| William Jones (UK) Ltd | Liverpool | 2013 |
| William Joshua Templeton Limited | Totnes | 2021 |
| William Lambie Limited | Kilmarnock | 1957 |
| William Love,Limited | Bishop Auckland | 1910 |
| William Marsden & SON Limited | Sheffield | 1955 |
| William Martin (Littleport) Limited | Ely | 1987 |
| William Mcgregor & SON Limited | Carluke | 2013 |
| William Mitchell & Sons Limited | Lanark | 1985 |
| William Morfoot Limited | Thetford | 1962 |
| William Morrison Private Property Limited | Wellington | 2021 |
| William Norman & Son,Limited | Walsoken | 1951 |
| William Notcutt Estates Limited | Woodbridge | 2011 |
| William O. Gordon (Bindal) Limited | Tain | 1952 |
| William Paterson Livestock Ltd | Stirling | 2019 |
| William Peat(Barnard Castle)Limited | Barnard Castle | 1956 |
| William Procter Limited | Southminster | 1982 |
| William Punton and SON Limited | Tweed, Northumberland | 2005 |
| William Reynolds (Farmers) Limited | Stamford | 1960 |
| William Ronald Forestry Ltd | By Lochgilphead | 2010 |
| William Seaman (Yaxham) Limited | Fakenham | 1957 |
| William Shearer | Kirkwall | 2013 |
| William Shearer Livestock Ltd | Strathaven | 2026 |
| William Smith (Wakefield) Limited | Scarborough | 1934 |
| William Speak(Farms)Limited | Devon | 1957 |
| William Taylor (Import/Export) Limited | Coleraine | 1986 |
| William Thompson (York) Limited | Malton | 1926 |
| William Thomson and SON (Tannadice) Limited | Forfar | 1955 |
| William Underwood Limited | Staffordshire | 2007 |
| William Wild & SON (Mollington) Limited | Chester | 1948 |
| William Wright & Sons (Farmers) Limited | Norwich | 1970 |
| William Young (Dereham) Limited | Norwich | 1955 |
| William Young (Fraserburgh) Limited | Fraserburgh | 2006 |
| William Young (Skerrington Mains) Limited | Kilmarnock | 1949 |
| Williams & Co Leisure Limited | Selby | 2026 |
| Williams & Gwilym Limited | Bodorgan | 2006 |
| Williams Administration Ltd | Belper | 2024 |
| Williams Agri Limited | Huntingdon | 2018 |
| Williams and Webb Fishing Limited | Penzance | 2025 |
| Williams Bros Margam Limited | Bridgend | 2011 |
| Williams Caernarfon Limited | Porthmadog | 2012 |
| Williams Civil Engineering Ltd | Llangadog | 2026 |
| Williams Equine Limited | Hayle | 2022 |
| Williams Equine Services Limited | Caldicot | 2015 |
| Williams Farm Services Limited | Scamblesby | 1980 |
| Williams Graig Ltd | Holywell | 2026 |
| Williams Horsepower Limited | High Wycombe | 2006 |
| Williams Marine Limited | Llanelli | 2017 |
| Williams Solar Farming Limited | Stamford | 2023 |
| Williams Tree Surgery Ltd | Huntingdon | 2017 |
| Williams Tree Works Ltd | Chorlay | 2021 |
| Williams Woolies Limited | Exeter | 2019 |
| Williams Woolly Sheep Company Limited | London | 2024 |
| Williamson - Orchard Limited | Shaftesbury | 2003 |
| Williamson Bros Shellfish Ltd | Tranent | 2018 |
| Williamson Brothers North West Limited | Ulverston | 2002 |
| Williamson Farming Ltd | Nantwich | 2023 |
| Williamson Solutions Ltd | Halkirk | 2012 |
| Williamsons Potatoes Limited | St Andrews | 2011 |
| Williamston Estates Limited | Aberdeen | 1963 |
| Williamston Farms Limited | Haverfordwest | 2004 |
| Willingham House Stud Ltd | Newmarket | 2003 |
| Willington and District Angling Club Ltd | Crook | 2018 |
| Willis Dairy Farmers Ltd | Tarporley | 2007 |
| Willis Equestrian Limited | Cardiff | 2017 |
| Willis Pest Control Ltd | West Bromwich | 2019 |
| Willjammer Limited | Gretton Corby | 1998 |
| Willon Orchard Honey Limited | Worksop | 2025 |
| Willoughby 395 Limited | Nottingham | 2002 |
| Willoughby Arms Limited | Watford | 1998 |
| Willoughby Dairy Ltd | London | 2025 |
| Willoughby Farms Limited | Alford | 1952 |
| Willoughby Tree Services Limited | Lincs | 2007 |
| Willow & Oak Limited | Stroud | 2016 |
| Willow & Riverstone Sidelands CIC | Bury St. Edmunds | 2025 |
| Willow 2001 Limited | Tenbury Wells | 2001 |
| Willow Barn Equestrian Limited | Stratford-Upon-Avon | 2023 |
| Willow Barn Organics Ltd | Caldicot | 2021 |
| Willow Bramley Ltd | Retford | 2022 |
| Willow Bridge Farm Limited | Cirencester | 2022 |
| Willow Contracts Ltd | Prestatyn | 2025 |
| Willow Farm Equestrian Ltd | Great Yarmouth | 2021 |
| Willow Farm Ltd. | Gorebridge | 2013 |
| Willow Farm Yorkshire Limited | Rotherham | 2022 |
| Willow Farming Limited | Woodhall Spa | 1994 |
| Willow Field Little Pet Boarding Ltd | Moss | 2024 |
| Willow Forge Stables Limited | Carlton- On- Trent | 2025 |
| Willow Green Kennels Limited | Dyfed | 2005 |
| Willow Grove Allotments Limited | Chislehurst | 2020 |
| Willow Grove Farm Limited | Brandon | 2020 |
| Willow Hands & Co Ltd | Norwich | 2026 |
| Willow Highlands Ltd | Highbridge | 2026 |
| Willow Holdin Ltd | Wakefield | 2019 |
| Willow House Stables Limited | Ely | 2020 |
| Willow Marsh Fishery Ltd | Cradley Heath | 2009 |
| Willow Royd Stables Ltd | Hebden Bridge | 2023 |
| Willow Saplings Ltd | Banbury | 2015 |