| John Chapman Conservation Ltd | Skipton | 2025 |
| John Chapman Farms Limited | Huntingdon | 1965 |
| John Chapman Landscapes Ltd | Skipton | 2025 |
| John Chester Limited | Bridgnorth | 2009 |
| John Clegg Consulting Limited | Mid Lothian | 2002 |
| John Close & SON Limited | Berwick-Upon-Tweed | 1947 |
| John Cole Farms Limited | Norwich | 1987 |
| John Coleman & Sons(Farmers)Limited | Dorchester | 1961 |
| John Compton Limited | Newtownabbey | 1918 |
| John Cooper Farming Ltd | Shefford | 2025 |
| John Cooper Farms Limited | Louth | 1981 |
| John Coulthurst (EGG Packers) Limited | Preston | 1958 |
| John Crop Development International Limited | Portsmouth | 2020 |
| John Cross & Sons Limited | Ness | 1948 |
| John Cullen Gardens Ltd | Manchester | 2012 |
| John D Nicol Ltd. | Fraserburgh | 2006 |
| John Darby (1959) Limited | Nottingham | 1959 |
| John Davies (Farms) Limited | Shropshire | 1975 |
| John Deere Forestry Limited | Altrincham | 1988 |
| John Dobson & SON (Carlton) Limited | Wakefield | 1952 |
| John Dorse Ltd | Devon | 2003 |
| John Douglas Farming Limited | Edinburgh | 2019 |
| John Edgar Agricultural Services Limited | Retford | 2016 |
| John Evans Farmers Limited | Bromsgrove | 1972 |
| John Farbon & Company Limited | Ledbury | 1973 |
| John Fiddes Limited | Alnwick | 2005 |
| John Fisher (NI) Ltd | Co Down | 2003 |
| John Foord & Co. Limited | 3 Dorset Rise | 1997 |
| John Fuller Trees Limited | Newton Abbot | 2010 |
| John Fyfe & SON (ELY) Limited | Diss | 1970 |
| John G Alexander Limited | Forfar | 2003 |
| John G Morris Limited | Denbigh | 2015 |
| John G Smith Limited | Canonbie | 2023 |
| John Gale Limited | Hungerford | 1958 |
| John Giddings (Farms) Limited | Melksham | 1973 |
| John Gordon & SON Limited | Nairn | 1985 |
| John Gough Limited | Shrewsbury | 1972 |
| John Graham Contractors Ltd | Tarbert | 2011 |
| John Grant (Donington) | Boston | 1987 |
| John Gregory & Sons (Timber Merchants) Limited | Darley Dale | 1924 |
| John H. Cocks & Sons (Farmers) Limited | Warwickshire | 1965 |
| John Hancock Oflo Services Grimsby Ltd | Grimsby | 2011 |
| John Hannah Fishing Ltd | Macduff | 2014 |
| John Harding and SON Limited | Winsford | 2012 |
| John Harmer Ltd | Shrewsbury | 2002 |
| John Hart Limited | Harrogate | 2012 |
| John Hatcher & Company Limited | Felixstowe | 1977 |
| John Henderson Contracting Ltd | Avoch | 2018 |
| John Higgins & SON Limited | Nr Shrewsbury | 1993 |
| John Hofer Limited | Hampton | 1974 |
| John Holliday (Ludlow) Limited | Stourport-On-Severn | 2006 |
| John Holman Properties Limited | Wickford | 2004 |
| John Hunkin Limited | St. Austell | 2014 |
| John Hunter Limited | Castlederg | 2003 |
| John Hurle & Sons Limited | Truro | 2004 |
| John Hurst & Sons Limited | Ormskirk | 2025 |
| John J Mckenna Ltd. | London | 2026 |
| John Jiggens Limited | Manningtree | 2010 |
| John K. Dunlop Limited | Girvan | 1964 |
| John Kelly Fresh Fish Limited | Brixham | 2008 |
| John Kingslake Limited | Lichfield | 1959 |
| John Knox Farms Limited | Forfar | 2002 |
| John Lake Shellfish Limited | King'S Lynn | 1994 |
| John Langmead Ltd | Winchester | 2018 |
| John Lawrence Limited | Llandrindod Wells | 2003 |
| John Lawrie (Tillyrie) Limited | Kinross | 1983 |
| John LEA & Sons Limited | Much Wenlock | 2017 |
| John Liddiard Farms Limited | Newbury | 1978 |
| John Lory (Farmers) Limited | Horley | 1964 |
| John M Fisher Ltd. | Stranraer | 2011 |
| John M Lawrie | Arbroath | 1951 |
| John M. Dodds Limited | Brigg | 1975 |
| John M. Wight Limited | | 1990 |
| John Macalister (Oban) Limited | Argyll | 1994 |
| John Makin Limited | Bridlington | 1964 |
| John Mason Limited | Swadlincote | 2002 |
| John Mccolm Ltd | Wigtownshire | 2014 |
| John Mclaren Agriculture Ltd | Chelmsford | 2011 |
| John Mcneil Wilson Limited | Kings Lynn | 1948 |
| John Melville & Company Limited | | 1956 |
| John Millman Limited | Hereford | 2008 |
| John Monnington Farms Limited | Lewes | 1957 |
| John Murray (N.I.) Ltd | Draperstown | 2014 |
| John Murray Farming Ltd | Stockton-On-Tees | 2020 |
| John Neal Farms (Benington) Limited | Benington | 1982 |
| John Neal Farms (Sibsey) Limited | Boston | 1982 |
| John Nicholson Associates Limited | Rowlands Gill | 2000 |
| John O. Gordon Limited | Inverness | 1954 |
| John O.V. Ltd. | Peterhead | 2004 |
| John Oliver (Moors Farm) Limited | East Riding Of Yorkshire | 2003 |
| John P Clark Limited | Strathpeffer | 1982 |
| John P Gray and SON | Angus | 2001 |
| John P.Gee & Sons Limited | Oxford | 1957 |
| John Paine (Kent) Potatoes Limited | Ashford | 1939 |
| John Parker Limited | Southampton | 1990 |
| John Parr & Sons (Farms) Limited | St. Helens | 1964 |
| John Pearce Racing Limited | London | 1998 |
| John Percival (Farms) Limited | Nr. Northwich, | 1959 |
| John Pollock & Sons Limited | | 2007 |
| John R Montgomery Limited | Birchington | 1977 |