| J.H.Dorrington & Son(Dunsby)Limited | | 1958 |
| J.H.Hall and Son(Farms)Limited | Dorchester | 1956 |
| J.H.Heathcote Limited | Rugeley | 1959 |
| J.H.Joyce & Sons Limited | Bedford | 1963 |
| J.H.Newington Limited | Woking,Surrey | 1962 |
| J.H.P. Farming Limited | Swindon | 1992 |
| J.H.Wormington and SON Limited | Bromsgrove | 1961 |
| J.Hind & SON Limited | Kettering | 1954 |
| J.Hole & Sons Limited | Chesterfield | 1957 |
| J.I. Brown Ltd | Newry | 2011 |
| J.I.H. Jones & Son(Erwgilfach)Limited | Powys | 1964 |
| J.J. & T.H.Haylock Limited | Haverhill | 1959 |
| J.J. Fishing Ltd. | Fraserburgh | 2008 |
| J.J. Homes Limited | Berwick-Upon-Tweed | 2009 |
| J.J. Steeples & Sons Limited | Eastwood | 1958 |
| J.J.& W.Alston Limited | Erpingham | 1951 |
| J.J.&D.S.Stubley Limited | Scunthorpe | 1955 |
| J.J.Furness Limited | Matlock | 1949 |
| J.J.W.Eckley & Sons Limited | Faversham | 1961 |
| J.Jackson Limited | Barnetby | 1956 |
| J.K. Farms Limited | Laindon | 1976 |
| J.K. Genetics Ltd | Dungannon | 2018 |
| J.K. Rogers & SON Limited | Ripon | 1964 |
| J.K.B.Megginson & Sons Limited | Driffield | 1964 |
| J.K.Longman Limited | Shepton Mallet | 1958 |
| J.K.W.Alexander Limited | Faversham | 1951 |
| J.L UK Developments Ltd | Barnetby Le Wold | 2015 |
| J.L. Ashby & Company Limited | Milton Keynes | 1942 |
| J.L. Farms Limited | Spalding | 1929 |
| J.L. Gladwin Farms Limited | Gainsborough | 1985 |
| J.L. Wright Limited | Rochester | 1950 |
| J.Latham Ltd | Sutton Coldfield | 2024 |
| J.M. Cochran Limited | Kirkcaldy | 1956 |
| J.M. Newling & SON Limited | Wisbech | 1978 |
| J.M.I. Agricultural Contractors Limited | Maldon | 2001 |
| J.M.P. Thomas 1909 Limited | Shrewsbury | 2023 |
| J.M.Robinson & SON Limited | Leeds | 1955 |
| J.M.T. Engineering (Ladbroke) Limited | Southam | 2003 |
| J.N. Wigley Limited | Oswestry | 2014 |
| J.N.Fuller-Shapcott & Co. | | 1984 |
| J.O. Jackson & Sons Limited | Little Downham | 1958 |
| J.O.Adams & SON Limited | Northampton | 1955 |
| J.Owen Day.Limited | Gainsborough | 1958 |
| J.P.A. Dickinson Farms Limited | Gainsborough | 1969 |
| J.P.Farms Limited | Leominster | 2000 |
| J.P.Matthews Limited | Somerset | 1961 |
| J.P.Obrien Ltd | Leamington Spa | 2017 |
| J.P.S. Farming Limited | Hampshire | 1995 |
| J.Peacock & Sons Limited | Thetford | 1946 |
| J.Peters Agricultural Services Ltd | Watford | 2024 |
| J.R. & J. Webster (Halsall Farms) Limited | Halsall, Near Ormstirk | 1978 |
| J.R. & S.R. Webber Limited | Blandford Forum | 1964 |
| J.R. Clark Limited | Grantham | 1981 |
| J.R. Cumming Services Ltd | Ellon | 2012 |
| J.R. Farm Meats Limited | Ashford | 2000 |
| J.R. Glew Junior & Co. Limited | Scunthorpe | 1976 |
| J.R. Greenfield Limited | Louth | 1960 |
| J.R. Macgregor (Dyke) Limited | Glasgow | 1991 |
| J.R. Percival Limited | Market Harborough | 1972 |
| J.R. Sykes Farms | Winchester | 1973 |
| J.R.F. James & Sons Limited | Haverfordwest | 2003 |
| J.R.Gardiner Limited | Bridlington | 1962 |
| J.R.Gilman & SON Limited | Staffordshire | 1964 |
| J.R.Griffin & Sons(Bulkington)Limited | Devizes | 1946 |
| J.R.Styles Limited | Near Bewdley | 1958 |
| J.R.Taylor Contracting Ltd | Coleshill | 2019 |
| J.R.Temple & Sons,Limited | Berwick-Upon-Tweed | 1939 |
| J.Rainford and Sons Limited | Nr Chorley | 1964 |
| J.Rayner & Sons Limited | London | 1954 |
| J.S. Salmon Limited | Argyll | 1990 |
| J.S.(Farms)Limited | Boston | 1963 |
| J.S.Dakin & Company | Newark | 1947 |
| J.S.F.Hood Limited | Lincoln | 1956 |
| J.S.Garton & SON Limited | Bishop'S Stortford | 1963 |
| J.S.Morton & Sons Limited | West Yorkshire | 1965 |
| J.S.R. Farms Limited | Driffield, East Yorks. | 1975 |
| J.S.R. Genetics Limited | Hessle | 2000 |
| J.S.Tree&Garden Services Ltd | Ipswich | 2025 |
| J.Salmon & Partners Ltd | Milton Keynes | 2015 |
| J.T. Clarke (March) Limited | March | 1977 |
| J.T. Nixon & Sons Ltd | Hexham | 2004 |
| J.T.Dixon & Sons(Whitley Bridge)Limited | Nr Goole | 1943 |
| J.T.Hollis(Farms)Limited | Lincoln | 1951 |
| J.T.Peach & SON Limited | Spalding | 1960 |
| J.T.Venables(Kempsey)Limited | Worcester | 1945 |
| J.Turner & Co.,Limited | Much Hoole | 1923 |
| J.V.B. Buchan Ltd. | Fraserburgh | 2003 |
| J.V.Lloyd | Rugby | 1959 |
| J.V.Sleightholme Limited | Scarborough | 1958 |
| J.V.Waugh & SON Limited | Black Notyey, Braintree | 2007 |
| J.W. & N.J. Stokoe Limited | Berwick Upon Tweed | 2020 |
| J.W. Amps Limited | Diss | 1957 |
| J.W. Frith Ltd. | Maidstone | 1983 |
| J.W. Home Farming Limited | Shrewsbury | 2008 |
| J.W. Marris & Sons Limited | Lincoln | 1976 |
| J.W. Needham Limited | Louth | 1953 |
| J.W. Nichols (Poultry) Limited | Bristol | 1974 |
| J.W.Ashmore Limited | Enderby Leicester | 1962 |
| J.W.Barker and SON Limited | Near Worcester | 1965 |
| J.W.Boyd & Sons Limited | Ashford | 1961 |