| Collaborate Recruitment Ltd | Administrative & support | 2019 |
| Collectamaniaindorset Ltd | Wholesale & retail | 2024 |
| Collective Vision Film Limited | Information & communication | 2016 |
| Collectors Bubble Limited | Wholesale & retail | 2013 |
| Collingwood Farm (Camberley) Management Company Limited | Households | 1997 |
| Colt Mortgages Ltd | Financial services | 2026 |
| Coltunach Limited | Other services | 2025 |
| Combined Computer Resources Limited | Information & communication | 1998 |
| Comedy Clubs Limited | Other services | 2005 |
| Comeni Anaesthetic Services Limited | Health & social care | 2013 |
| Comfortable Place Limited | Construction | 2021 |
| Comilla Court (Branksome) Limited | Households | 1961 |
| Commando Conditioned Ltd | Arts & recreation | 2021 |
| Commerce on Demand Network Ltd | Wholesale & retail | 2012 |
| Commercial Kitchen Services (SW) Ltd | Manufacturing | 2014 |
| Commercial Property Lending Ltd | Financial services | 2021 |
| Commercial Washrooms Ltd | Extraterritorial | 2012 |
| Commodore Electronics Ltd | Wholesale & retail | 2025 |
| Common Ground Creative Consultancy Limited | Professional & scientific | 2025 |
| Common Roots Cacao Ltd | Wholesale & retail | 2021 |
| Common Supply AU Ltd | Hospitality | 2026 |
| COMMUNIC8 Ltd | Education | 2025 |
| Communication Graphics (Bristol) Limited | Arts & recreation | 1999 |
| Community Action Network | Administrative & support | 2000 |
| Community Armchair Ltd | Information & communication | 2025 |
| Community Rhythms CIC | Hospitality | 2013 |
| Comol Business Services Limited | Professional & scientific | 2010 |
| Comp Vault's UK Limited | Other services | 2025 |
| Companions 4 Life CIC | Professional & scientific | 2020 |
| Compare Aware Ltd | Information & communication | 2024 |
| Compariqo Limited | Administrative & support | 2018 |
| Compass (Alexander Associates) Ltd | Administrative & support | 2020 |
| Compass (Build Space) Ltd | Administrative & support | 2025 |
| Compass (ECS) Ltd | Administrative & support | 2020 |
| Compass (Edenmarsh) Ltd | Administrative & support | 2025 |
| Compass (Energi) Ltd | Administrative & support | 2024 |
| Compass (FBR) Ltd | Administrative & support | 2024 |
| Compass (Ignition) Ltd | Administrative & support | 2021 |
| Compass (Innovate) Ltd | Administrative & support | 2024 |
| Compass (Ionic) Ltd | Administrative & support | 2025 |
| Compass (LHI) Ltd | Administrative & support | 2025 |
| Compass (Precision) Ltd | Administrative & support | 2024 |
| Compass (Primis) Ltd | Administrative & support | 2025 |
| Compass (Pro) Ltd | Administrative & support | 2022 |
| Compass (Rhino) Ltd | Administrative & support | 2024 |
| Compass (Rssw) Ltd | Administrative & support | 2021 |
| Compass (Rtriibe) Ltd | Administrative & support | 2023 |
| Compass (Vertex) Ltd | Administrative & support | 2022 |
| Compass (Worldwide) Ltd | Administrative & support | 2024 |
| Compass CE Ltd | Administrative & support | 2019 |
| Compass Intelligence Limited | Information & communication | 2024 |
| Compass Point Building RTM Ltd | Households | 2013 |
| Compass Point Freehold Company Limited | Households | 2016 |
| Compass Point One Ltd | Manufacturing | 2024 |
| Compass Vallum Solutions Ltd | Administrative & support | 2025 |
| Compass Visuals Ltd | Information & communication | 2026 |
| Competition Vault Ltd | Information & communication | 2026 |
| Complete Interior Commercial Solutions Ltd | Construction | 2017 |
| Complete Removals & Storage Ltd | Other services | 2017 |
| Complete Roofing Solutions (Dorset) Ltd | Construction | 2021 |
| Complete Timber Window Solutions Ltd | Construction | 2024 |
| Completely Crystals Limited | Wholesale & retail | 2014 |
| Complex Asset Management Solutions Ltd | Information & communication | 2015 |
| Complex Solutions Forge Ltd | Information & communication | 2023 |
| Compli Group Ltd | Wholesale & retail | 2001 |
| Complianz Limited | Professional & scientific | 2010 |
| Compo Closet Ltd | Manufacturing | 2021 |
| Composite Profiles Group Limited | Construction | 2025 |
| Composite Profiles UK Limited | Construction | 2001 |
| Compound Factory Ltd | Professional & scientific | 2025 |
| Compound Mind Ltd | Financial services | 2021 |
| Compound Property Development Limited | Real estate | 2021 |
| Compton Acres Limited | Arts & recreation | 2002 |
| Compton Bournemouth Limited Liability Partnership | | 2024 |
| Computer Supplies Direct Limited | Administrative & support | 2001 |
| Computers Solutions Ltd | Information & communication | 2022 |
| Comverse Logisnext Limited | Wholesale & retail | 2026 |
| Conain Ltd | Wholesale & retail | 2021 |
| Concentrate Limited | Information & communication | 2003 |
| Concentrated Coolants Limited | Manufacturing | 2009 |
| Concept Axel Ltd | Professional & scientific | 2018 |
| Concept Construction Solutions Limited | Construction | 2012 |
| Concept Management Services Ltd | Administrative & support | 2006 |
| Concept Sails Limited | Manufacturing | 2004 |
| Concord Way (Dukinfield) Limited | Households | 1971 |
| Concrete Housing Ltd | Real estate | 2022 |
| Concrete VC I (Opco) Ltd | Financial services | 2022 |
| Concrete VC I FP LLP | | 2022 |
| Concrete VC I GP LLP | | 2022 |
| Concrete VC I LP | | 2022 |
| Concrete VC Partners LLP | | 2022 |
| Condor Ferries Limited | Transport & logistics | 1987 |
| Condor Limited | Transport & logistics | 1995 |
| Condor Logistics Limited | Transport & logistics | 1964 |
| Condor Marine Services Limited | Transport & logistics | 1995 |
| Condor Port Agencies Limited | Transport & logistics | 2002 |
| Condor UK Holdings Limited | Transport & logistics | 2002 |
| Cone Cloud Consulting Limited | Information & communication | 2016 |
| Conecap Limited | Financial services | 2021 |
| Confex Technology (Holdings) Limited | Manufacturing | 2014 |