| Colton Contracts Limited | Co Tyrone | 2001 |
| Coltsford Mill Trout Club Limited | Oxted | 1999 |
| Columbjohn Farm Limited | Exeter | 2002 |
| Colwidhen Asset Management Ltd | Dumfries | 2024 |
| Colwyn Contracting Limited | Taunton | 2025 |
| Colziumbea Limited | Glasgow | 2005 |
| Combe HAY Vineyard Ltd | Bath | 2021 |
| Combe Martin Scaffolding Limited | Barnstaple | 2021 |
| Combe Technologies Ltd | Minehead | 2022 |
| Combeshead Farm Limited | Tiverton | 2022 |
| Combi Corporation Ltd | London | 2013 |
| Combined Counties Properties Limited | Esher | 1978 |
| Combley Fish Farm Limited | Shanklin | 2026 |
| Comfeeds (Ipswich) Limited | Bristol | 1984 |
| Comfort Acres Ltd | Bournemouth | 2022 |
| Comm Couragous Ltd | Annan | 2016 |
| Commanche Stud Limited | Kent | 2006 |
| Command Marine Services Ltd | Dundee | 2026 |
| Commando Canines Dog Walking Ltd | Alexandria | 2023 |
| Commercial and Marine Comms Limited | King'S Lynn | 2003 |
| Commercial and Plant Spraying Ltd | Magherafelt | 2018 |
| Commercial Arboriculture Ltd | London | 2019 |
| Commercial Arborists Ltd | Stafford | 2014 |
| Commercial Bird Control Limited | Gloucester | 2018 |
| Commercial Farmers Group Ltd | Brigg | 2015 |
| Commercial Green Maintenance Ltd | Solihull | 2025 |
| Commercial Mushroom Growers UK Ltd | Louth | 2019 |
| Commercial Timber Sales Limited | Fleet | 1991 |
| Common Cause Co-Operative Limited | Lewes | 1994 |
| Common Cloth CIC | Manchester | 2025 |
| Common Farm Highbridge Ltd | Hereford | 2025 |
| Common Farm Livery Ltd | Highworth | 2023 |
| Common Farm,Limited | Ely | 1945 |
| Common FIG Limited | Cardiff | 2021 |
| Common Flora Ltd | Totnes | 2019 |
| Common Ground Environmental Ltd | Sheffield | 2026 |
| Common Land Wines Limited | St. Leonards-On-Sea | 2026 |
| Common Vegetation Management Limited | St. Austell | 2019 |
| Commonwork Organic Farms Limited | Edenbridge | 1986 |
| Commore Farm Ltd | Glasgow | 2015 |
| Communitas Limited | Presteigne | 2007 |
| Community Apothecary CIC | London | 2021 |
| Community Composting C.I.C. | Middlesbrough | 2022 |
| Community Flower Farm Ltd | High Wycombe | 2021 |
| Community Forest Land Trust | Liverpool | 2013 |
| Community Forest Services Ltd | Stafford | 2018 |
| Community Forest Trust | Liverpool | 1998 |
| Community Nutrition Farm Ltd | Nottingham | 2026 |
| Community Orchard Project South East CIC | Haslemere | 2019 |
| Community Patch Project CIC | Wincanton | 2023 |
| Community Patchwork Farm CIC | Truro | 2024 |
| Community Regeneration Outreach Projects Limited | Plymouth | 1999 |
| Community Roots Cornwall CIC | Penryn | 2021 |
| Community Tatton CIC | Altrincham | 2020 |
| Community Woodland Enterprise Community Interest Company | Kilmartin | 2010 |
| Compact Contracting Services Limited | Saffron Walden | 2022 |
| Company Accounts Limited | Hessle | 1995 |
| Compass Agronomy Limited | Chester | 2020 |
| Compass Pest Solutions Ltd | Nr Abingdon | 2025 |
| Compass Rose Shell Fisheries Limited | Ilfracombe | 2009 |
| Complete Animal Health Limited | Richmond | 2004 |
| Complete Bio-Nutrient Solutions (Cbns) Limited | Harrogate | 2019 |
| Complete Care Fertility Clinic Limited | Brmingham | 2018 |
| Complete Equine Hoofcare Ltd | Maidstone | 2012 |
| Complete Farming & Contracting Co Ltd | Peterborough | 2019 |
| Complete Lawn Services Limited | Runcorn | 2007 |
| Complete Pest Control Enfield Ltd | London | 2023 |
| Complete Tree Care Limited | Shrewsbury | 2001 |
| Complete Tree Services (UK) Limited | Oxford | 2001 |
| Complete Tree Solutions Ltd | Huddersfield | 2025 |
| Completely Different Solutions Limited | Stevenage | 1998 |
| Complex Forests Limited | London | 2023 |
| Compton Beauchamp Estates Limited | Faringdon | 1999 |
| Compton Chamberlayne Farms Limited | Salisbury | 1997 |
| Compton Grove Farm and Stables Limited | Wetherby | 2022 |
| Compton Hall Pigs Ltd | Fakenham | 2016 |
| Compton Industries Ltd | Cockermouth | 2011 |
| Compton Manor Estates Limited | London | 1968 |
| Compubarn Limited | Wiltshire | 1985 |
| Comrie Investments Limited | Perth | 2009 |
| Comutiny Ltd | Birmingham | 2018 |
| Conagleann Limited | Forfar | 2012 |
| Concept Cowhouse Ltd | Ross-On-Wye | 2006 |
| Concord Farms Limited | Belfast | 2009 |
| Concord Fishing Ltd | Shetland | 2023 |
| Concord Land Management Ltd | Berkhamsted | 2026 |
| Coney and Naylors Spring Wood Ltd | Amersham | 2016 |
| Coney Smallholding Ltd | Great Missenden | 2026 |
| Coneygarth Farm Ltd | Ashington | 2017 |
| Coneywood Kennels Ltd | March | 2015 |
| Confident Canine Ltd | Burton-On-Trent | 2024 |
| Congash Estate Ltd | Turriff | 2018 |
| Congham Farms Limited | Kings Lynn | 2001 |
| Congleton Lawn Turf Limited | Congleton | 2003 |
| Conheeney Group Ltd | Benfleet | 2023 |
| Conhess Limited | London | 2016 |
| Conibear Contracting Ltd | Kettering | 2015 |
| Conifera Holdings Ltd | Solihull | 2011 |
| Conigre Game Farm Ltd | Nr Cheltenham | 2004 |
| Coning Fertiliser Limited | York | 2011 |