| Casewick Stud Equestrian Limited | Stamford | 2016 |
| Casey Agri Ltd. | London | 2015 |
| Casey Tree Care & Landscape Services Ltd | Glasgow | 2008 |
| Cash Hill Farm Limited | Ballinamallard | 2014 |
| Cashel Farm Ltd | Armagh | 2023 |
| Cashel Forest Trust | Bridge Of Allan | 1995 |
| Cashmere UK Limited | Swansea | 1988 |
| Cashmore Farming Ltd | Buxton | 2023 |
| Casimir Equestrian Limited | Leicester | 2026 |
| Caspence Ltd | Peterborough | 2024 |
| Cassels Farm Limited | Warminster | 1962 |
| Casserly & Sons Limited | Uckfield | 2005 |
| Cassidy Farms Ltd | Brentwood | 2008 |
| Cassidy Group Ltd | Brentwod | 2008 |
| Cassidy Livestock Ltd | Brentwood | 2008 |
| Cassidy's Poultry Ltd | Enniskillen | 2023 |
| Cassie White Equine Services Ltd | Leighton Buzzard | 2026 |
| Cassie Woods Limited | Northumberland | 2004 |
| Cassiltoun Trust | Glasgow | 2000 |
| Cassiobury Rare Breeds Farm & Fisheries Limited | Liskeard | 2026 |
| Cassywater Outdoors Ltd | Newry | 2020 |
| Cast & Catch Ltd | Hull | 2025 |
| Cast and Connect CIC | Bristol | 2025 |
| Cast Fisheries Ltd | Chorley | 2011 |
| Castell Dwyrain Farms Ltd | Carmarthen | 2002 |
| Castell Gorwyn Farm Ltd | Dyfed | 2003 |
| Castelvy Spaniels Ltd | York | 2025 |
| Castle Brea Farm C.I.C. | Penzance | 2022 |
| Castle Erectors Limited | Barnstaple | 1996 |
| Castle Farm Boarding Kennels Limited | Nuneaton | 2009 |
| Castle Farm Limited | Maidstone | 2006 |
| Castle Farm Livery & Cross Country Ltd | Wotton-Under-Edge | 2025 |
| Castle Farm Organics Limited | Bath | 2013 |
| Castle Farms Nottingham Limited | Derby | 2025 |
| Castle Fields Farm Limited | Buckingham | 2025 |
| Castle Fields Holdings Limited | Buckingham | 2025 |
| Castle House Agriculture Limited | Banbury | 2009 |
| Castle Kids' Patch CIC | Stoke-Sub-Hamdon | 2025 |
| Castle LEA Ground Ltd | Chard | 2025 |
| Castle Park Farm and Smallholdings Ltd | Haddington | 2022 |
| Castle Sporting Shoot Limited | Cockermouth | 2015 |
| Castle Tree Care Limited | Louth | 2015 |
| Castle Trees Arborists Ltd | Edinburgh | 2025 |
| Castle Wood Dinas Powys Ltd | Dinas Powys | 2024 |
| Castlebridge Agency Limited | Bury St. Edmunds | 2021 |
| Castlebrook Farms Limited | Fivemiletown | 2012 |
| Castledillon Estate Ltd | Armagh | 2020 |
| Castlefield Dog Rescue CIC | Nottingham | 2022 |
| Castlefield Kennels Limited | Nottingham | 2014 |
| Castlegate Development Limited | Penrith | 2019 |
| Castlegreen Farms Limited | Limavady | 2011 |
| Castlehaven Limited | Southampton | 2003 |
| Castlelaw Marketing Limited | Kinross | 2009 |
| Castlemains Farm Ltd | Juniper Green | 2024 |
| Castlemead Poultry Limited | Bath | 2020 |
| Castlemurray Farms Limited | Omagh | 2014 |
| Castlepark Livestock Ltd | Dalry | 2025 |
| Castles Equine Ltd | Liverpool | 2023 |
| Castles Estate Limited | Winchester | 2016 |
| Castleside Farm Ltd | Ashkirk | 2020 |
| Castlesteads Farms Limited | Cumbria | 2006 |
| Castleton Farm Limited | Dunfermline | 2020 |
| Castleton for Agricultural Technology & Development Ltd | Wembley | 2020 |
| Castleton Turf and Soil Suppliers Ltd | Newport | 1998 |
| Castleview Stud Limited | Knutsford | 2025 |
| Castlewellan Agricultural Show Limited | Ballynahinch | 2009 |
| Castlewellan Community Allotments Limited | Newcastle | 2023 |
| Castlewood Fishing Limited | Hessle | 2013 |
| Castruriali Ltd | London | 2023 |
| Caswell Forestry Ltd | Hawick | 2010 |
| Catacol Limited | Belper | 2003 |
| Catalan Ridge Equestrian Ltd | Dawlish | 2025 |
| Catch 22 Baits Limited | Corby | 2015 |
| Catch a Smile CIC | Gloucester | 2019 |
| Catch of the Sea Limited | Romford | 2025 |
| Catchburn Vineyard Limited | Morpeth | 2023 |
| Catchpulse Limited | Balsall Common | 1991 |
| Catfield Spuds Limited | Norwich | 2012 |
| Catfoss Airfield Limited | Ross-On-Wye | 2022 |
| Cathal Shivers Ltd | Castledawson | 2024 |
| Catherine Coley Ltd | Kidderminster | 2002 |
| Catherine's Horse Stables Ltd | Welwyn | 2021 |
| Cathy & Dave Barnes Ltd | Osbaldeston | 2015 |
| Catkins and Clematis Ltd | Southam | 2022 |
| Catlane Friesians Ltd | Nuneaton | 2016 |
| Catnaps Farm Limited | Leeds | 2013 |
| Catnip Castle Hotel Ltd | Kinross | 2017 |
| Caton Agricultural Limited | Warwickshire | 1984 |
| Catopia Limited | West Sussex | 2006 |
| Cator Blackaton Farming Limited | London | 2006 |
| Cats Away Limited | Manchester | 2025 |
| Cats Diary Ltd | Weymouth | 2025 |
| Cats Whiskers 1988 Limited | Tunbridge Wells | 2022 |
| Catshead Limited | Stevenage | 2006 |
| Cattell Brothers Limited | Denbigh | 1953 |
| Cattell Crop Services Ltd. | Inverness | 2002 |
| Cattle (Holderness) Limited | Ottringham | 1958 |
| Cattle Genie Limited | Ilkley | 2015 |
| Cattle Loan Company Limited | Carnforth | 2017 |
| Cattle Services (AYR) Limited | Ayr | 1965 |