| C.T.Hobson Limited | York | 2026 |
| C.Tomlinson Limited | Lincoln | 1959 |
| C.W. & J. Cargill Limited | Saxmundham | 1960 |
| C.W. Anyan (Farms) Limited | Market Rasen | 1974 |
| C.W. Dobbs & SON Limited | West Pinchbeck | 1963 |
| C.W. Udale Limited | Rutland | 1943 |
| C.W.C. Green Farms Limited | Woodbridge, | 1960 |
| C.W.Cave(Terrington)Limited | King'S Lynn | 1951 |
| C.W.P. Wilkes and SON Limited | Stourbridge | 1980 |
| C.W.Parker(Wainfleet)Limited | Skegness | 1951 |
| C.Wright & SON Gedney Limited | Norwich | 1950 |
| C.Wylie & SON Limited | Tamworth | 1958 |
| C2C Marine Ltd | Banff | 2022 |
| C2H Online Ltd | Bracknell | 2019 |
| C2R Green Limited | Luton | 2023 |
| C39 Limited | Saffron Walden | 2020 |
| C3LD Limited | Lampeter | 2017 |
| C4C Network Ltd | Swindon | 2012 |
| CA & J Alty & SON Limited | Carnforth | 2012 |
| CA & WJ Supplies Limited | Huntingdon | 2016 |
| CA Feughside Limited | Forfar | 2010 |
| CA Negus Limited | Attleborough | 2024 |
| Caars Estates Limited | Preston | 2010 |
| CAB Agricultural Contractors Limited | Malpas | 2016 |
| CAB Contracting Ltd | St. Austell | 2021 |
| Caballo Limited | London | 2007 |
| Caballus Equine Services Limited | Peterlee | 2021 |
| Cable Logging Limited | Brechin | 2013 |
| Cabragh House Farms Ltd | Armagh | 2011 |
| Cabragh Ltd | Armagh | 2018 |
| Cabragh Poultry Limited | Armagh | 2025 |
| Cabrilla Dogs Limited | Southery | 2018 |
| Cacklebean Limited | Cheltenham | 2020 |
| Cactocereus Ltd | Sutton-In-Ashfield | 2023 |
| Cactus Shack Ltd | Ledbury | 2023 |
| Cactus Specialist UK Ltd | Tring | 2024 |
| Cadbury Angling Limited | Berkeley | 2022 |
| Cadbury Farms Limited | Cheltenham | 2018 |
| Caddicks Limited | Cinderford | 2005 |
| Caddis Limited | Macclesfield | 2008 |
| Caddow Wood Forestry and Farming Ltd | Gainsborough | 2026 |
| Caddyview Farms Limited | Antrim | 2023 |
| Cade Biofuels Ltd | Droitwich | 2012 |
| Cade Street Nursery Ltd | Heathfield | 2024 |
| Cadeleigh Farmco Limited | Tiverton | 2024 |
| Cadet (Eco) Ltd | Derby | 2021 |
| Cadian Feeds & Livestock Limited | London | 2023 |
| Cadian Feeds Limited | Dungannon | 2018 |
| Cadian Livestock & Feeds Limited | Dungannon | 2026 |
| Cadogan Estates (Agricultural Holdings) Limited | London | 1964 |
| Caduceus Limited | Bromyard | 2001 |
| Cadwaladr Sons Ltd | Chester | 2013 |
| CAE Canfas Farm Limited | Llanelli | 2026 |
| CAE Felin CSA CIC | Swansea | 2021 |
| CAE Main Livery Ltd | Caernarfon | 2019 |
| CAE MOR Agri Limited | Llangollen | 2021 |
| CAE Newydd Enterprises Limited | Wrexham | 2007 |
| CAE Popdy Ltd | Glan Conwy | 2022 |
| CAE Sally Animal Rescue Ltd | Denbigh | 2024 |
| CAE TAN CSA C.I.C. | Swansea | 2015 |
| Caeau Bloodstock Limited | Pontrilas | 2023 |
| Caerau Market Garden Ltd. | Maesteg | 2024 |
| Caerfagu Products Limited | Llandrindod Wells | 1987 |
| Caergwrle Limited | Caldicot | 2022 |
| Caerhun Farm Ltd | Bangor | 2020 |
| Caerhys Organic Community Agriculture | Haverfordwest | 2013 |
| Caeriad CIC | Haverfordwest | 2022 |
| Caerus Estates (UK) Ltd | London | 2018 |
| Cagely Limited | Peterhead | 2017 |
| Cahir Linn Oysters Limited | Newry | 2017 |
| CAI Roberts CYF | Porthmadog | 2013 |
| Caiber Fishing Co Ltd | Isle Of Islay | 2025 |
| Caiplich Farm Ltd | Inverness | 2019 |
| Caird Potatoes Limited | Arbroath | 2009 |
| Cairn Equestrian Ltd | Leven | 2023 |
| Cairncroft Ltd. | Crieff | 2020 |
| Cairness Limited | Forfar | 1954 |
| Cairnfold House Equestrian Limited | Dunfermline | 2011 |
| Cairngaan Farms Limited | Stranraer | 1996 |
| Cairngall Farms | Peterhead | 1997 |
| Cairngorm Woodlands Ltd | London | 2022 |
| Cairngorms Crofters & Farmers Community Ltd | Kingussie | 2024 |
| Cairngryffe Gundogs Ltd | Biggar | 2019 |
| Cairnleigh Ltd | Craigavon | 2007 |
| Cairnleith Farms Limited | Angus | 2003 |
| Cairnrowan Farms Ltd | Ellon | 2022 |
| Cairnton Estate Limited | Aberdeen | 2006 |
| Cairnty Farms Ltd | Fochabers | 2023 |
| Caisley Eartag Ltd | Ipswich | 2013 |
| Caithness Chemicals Limited | Wick | 1989 |
| Caithness Crop Processing Limited | Thurso | 1993 |
| Caithness Potato Breeders Limited | Edinburgh | 1983 |
| Caithness Varieties Limited | Perth | 2001 |
| Cakeham Stables Ltd | Chichester | 2025 |
| CAL Fishing Ltd. | Shetland | 2011 |
| Cala Falco Ltd | London | 2026 |
| Caladh Estate Limited | Tighnabruaich | 2016 |
| Calancombe Estate Holdings Ltd | Ivybridge | 2015 |
| Calbac Ltd. | Mossbank | 2003 |
| Calcourt Farms Limited | Newtown | 2012 |