| Coco's Canine Creche Ltd | Other services | 2017 |
| Code Neon Ltd | Information & communication | 2025 |
| Cody Knows Code Ltd | Information & communication | 2025 |
| COE & COE Ltd | Hospitality | 2025 |
| Coffee NUT Ltd | Manufacturing | 2021 |
| Cognicent Limited | Professional & scientific | 2021 |
| Coldblow Farm Limited | Hospitality | 2026 |
| Coleman Commercials Ltd | Wholesale & retail | 2014 |
| Coles Property Maintenance and Refurbishment Ltd | Construction | 2020 |
| Collecteebles Ltd | Wholesale & retail | 2019 |
| Collie Inns Limited | Hospitality | 2019 |
| Collier Property & Asset Management Ltd | Real estate | 2025 |
| Collins Estimating Consultancy Limited | Professional & scientific | 2020 |
| Colortec (Wessex) Limited | Manufacturing | 2002 |
| Column Construction Limited | Construction | 2018 |
| Combat Fuel Supplements Limited | Manufacturing | 2021 |
| Combined Independents (Holdings) Limited | Wholesale & retail | 1963 |
| Comfort First Home Care Ltd | Health & social care | 2025 |
| Commeleon Ltd | Professional & scientific | 2020 |
| Commfire Limited | Information & communication | 2004 |
| Common Nature Learning Ltd | Information & communication | 2020 |
| Common Nature Sauna Ltd | Health & social care | 2026 |
| Community Infrastructure Partnership CIC | Health & social care | 2021 |
| Comnet Limited | Information & communication | 2017 |
| Complete Camper Repair Ltd | Manufacturing | 2023 |
| Completely Clean Services Ltd | Administrative & support | 2018 |
| Computerwise Information Technology Ltd | Other services | 2016 |
| CONA2K Productions Ltd | Information & communication | 2025 |
| Conholt Limited Partnership | | 2023 |
| Conholt Nominees Limited | Real estate | 2022 |
| Connexion Technologies Group Limited | Financial services | 2026 |
| Connexion Technologies Limited | Financial services | 2012 |
| Conquer Design Consultancy Limited | Administrative & support | 2015 |
| Conservation Collective Trading Limited | Other services | 2022 |
| Consolidated Mineral Estates Limited | Professional & scientific | 2021 |
| Consolidated Structures Limited | Construction | 2016 |
| Construction Docs Consulting Ltd | Professional & scientific | 2026 |
| Consult to Succeed Limited | Real estate | 2006 |
| Control Techniques Dynamics Limited | Manufacturing | 1962 |
| Convoy Digital Group Limited | Information & communication | 2020 |
| Cooper Foods (Andover) Limited | Wholesale & retail | 1991 |
| Cordero Properties Ltd | Real estate | 2021 |
| Cordner Interiors Limited | Construction | 2018 |
| Coreinsight Financial Advisory Ltd | Professional & scientific | 2025 |
| Corgi Services Limited | Other services | 1996 |
| Corndell Quality Furniture Ltd | Wholesale & retail | 2014 |
| Cornelius Murphy Ltd | Information & communication | 2020 |
| Cornwall and Garden House Limited | Households | 1980 |
| Corporate Utility Solutions Limited | Professional & scientific | 2016 |
| Correct Books Limited | Professional & scientific | 2012 |
| Correct Systems Limited | Information & communication | 2021 |
| Cort Services Limited | Professional & scientific | 2026 |
| Cottonworth LLP | | 2015 |
| Countess of Brecknock Hospice Trust | Health & social care | 1997 |
| Counton Ltd | Information & communication | 2025 |
| Country Canine Ltd | Manufacturing | 2024 |
| Country Cousins (Property Management) Limited | Real estate | 2001 |
| Country Fayre (UK) Ltd | Wholesale & retail | 2012 |
| Countryside Grounds Services Ltd | Administrative & support | 2024 |
| County Self-Storage Ltd | Transport & logistics | 2002 |
| Coventry Mechanical Services Ltd | Professional & scientific | 2017 |
| Covergirl Academy Ltd | Other services | 2013 |
| Cowdown Nursery Ltd. | Health & social care | 1995 |
| Coyenne Trade Co., Ltd | Wholesale & retail | 2025 |
| CPC Engineering Limited | Administrative & support | 2013 |
| CPM Lifts Limited | Construction | 2017 |
| Crafthouse Construction Ltd | Construction | 2025 |
| Craig Davenport Limited | Information & communication | 2007 |
| Crataegus Consulting Limited | Information & communication | 2017 |
| Crazy Dale’S Ltd | Hospitality | 2025 |
| Create Elevate Ltd | Professional & scientific | 2026 |
| Create the Ripple Ltd | Professional & scientific | 2017 |
| Creative Shine Marketing Ltd | Professional & scientific | 2025 |
| Cripps Tech Ltd | Information & communication | 2025 |
| Crivvens Limited | Information & communication | 2008 |
| Croombs C.A. Limited | Professional & scientific | 2006 |
| Cross IT Services Limited | Information & communication | 2017 |
| Cross Rental Limited | Administrative & support | 2017 |
| Crossfit Blockhouse Limited | Arts & recreation | 2014 |
| Crossley Bilborough Consultancy Limited | Professional & scientific | 2022 |
| Crosspoint Logistics Ltd | Transport & logistics | 2018 |
| Crownsterl Ltd | Transport & logistics | 2025 |
| Croxford Equine Veterinary Performance Ltd | Professional & scientific | 2025 |
| Crystal Clear AV Limited | Administrative & support | 2008 |
| Crysty Ltd | Administrative & support | 2014 |
| CSN Group Limited | Professional & scientific | 2024 |
| CT Financial Limited | Financial services | 2025 |
| Culinary Cultures Ltd | Hospitality | 2025 |
| Culinex Ltd | Hospitality | 2025 |
| Cupbot Ltd | Manufacturing | 2026 |
| Current Generation Ltd | Construction | 2010 |
| Custom Interconnect (Holdings) Limited | Manufacturing | 2011 |
| Custom Interconnect Limited | Manufacturing | 1986 |
| Custom Moulds and Mouldings Limited | Manufacturing | 1998 |
| Cutlass Logistics Limited | Administrative & support | 2014 |
| Cutty Brow Limited | Extraterritorial | 2023 |
| CVC Social Consultancy Limited | Health & social care | 2025 |
| CWJ Builders Ltd | Administrative & support | 2023 |
| Cyber Knowhow Ltd | Information & communication | 2020 |
| Cyberdispatch Ltd | Transport & logistics | 2026 |