| Clinical Aesthetics by Catherine Limited | Other services | 2024 |
| Clixa Ltd | Information & communication | 2014 |
| CLM Installation Services Limited | Construction | 2024 |
| CLM Mobile Smart Repair Limited | Wholesale & retail | 2024 |
| Cloburn International Ltd | Extraterritorial | 2007 |
| Clockwork Scaffolding Limited | Construction | 2020 |
| CLOTHES4THOSE in Need Ltd | Wholesale & retail | 2010 |
| Cloud Beauty Lounge Ltd | Other services | 2024 |
| Cloud Sales Consulting Limited | Information & communication | 2016 |
| CLOUD9CREATIONS Ltd | Wholesale & retail | 2021 |
| Cloudberry Limited | Administrative & support | 2000 |
| Cloudy Day Developments Ltd | Construction | 2026 |
| Cloverfields (Carlisle) Management Company Limited | Households | 2014 |
| Club Concrete Limited | Hospitality | 2003 |
| Club XS Limited | Extraterritorial | 1985 |
| CM Electrical Contractors Ltd | Construction | 2016 |
| CM Scaffolding Solutions Limited | Construction | 2023 |
| CM Stan Consulting Ltd | Extraterritorial | 2022 |
| CMD Financial Solutions Ltd | Financial services | 2008 |
| Cmooney Ltd | Transport & logistics | 2025 |
| CMR Developments (North West) Ltd | Construction | 2025 |
| CMR Rentals & Storage Ltd | Real estate | 2025 |
| CMT Autos & Commercials Limited | Wholesale & retail | 2025 |
| CN Combrink Properties Limited | Real estate | 2023 |
| CNN Motor Trading Limited | Wholesale & retail | 2022 |
| CNN Services Limited | Construction | 2016 |
| Coaching & Cultural Solutions Limited | Education | 2013 |
| Coaching Cultural Development Limited | Education | 2021 |
| Cobbled Cottages Limited | Real estate | 2023 |
| Cockermouth Kitchen Company Limited | Construction | 2002 |
| Coconut Thai Food Ltd | Hospitality | 2018 |
| Coffey Harvesting Limited | Agriculture & fishing | 2025 |
| Colbourne Investments Limited | Professional & scientific | 2017 |
| Cold Fell Group Limited | Financial services | 2008 |
| Coledale Limited | Construction | 2018 |
| Collective Essential Ltd | Wholesale & retail | 2025 |
| Collingwood House Newcastle LLP | | 2015 |
| Colmore Construction Limited | Real estate | 2021 |
| Colourmedia Solutions Limited | Information & communication | 2015 |
| Colourtext Limited | Professional & scientific | 2012 |
| Comfort&You Ltd | Wholesale & retail | 2023 |
| Commerce Media Limited | Information & communication | 1999 |
| Commonality Limited | Information & communication | 2001 |
| Community Action Nepal | Health & social care | 1997 |
| Community Club App Ltd | Professional & scientific | 2026 |
| Compass Cabling Systems Limited | Construction | 2003 |
| Complete Business Advisory Solutions Ltd | Professional & scientific | 2020 |
| Complete Engineering Services (Carlisle) Limited | Construction | 2003 |
| Complete Maintenance Carlisle Limited | Construction | 2024 |
| Complete Roofing Carlisle Limited | Construction | 2023 |
| Concept Accounting Limited | Professional & scientific | 2016 |
| Concept Support Limited | Professional & scientific | 2007 |
| Concrete Wall Panels Limited | Manufacturing | 2015 |
| Coney (York) Limited | Real estate | 2005 |
| Coniston Project Management Limited | Professional & scientific | 2013 |
| Construction Cost Consultants (Lincolnshire) Limited | Professional & scientific | 2014 |
| Construction Plant (Suppliers) Limited | Extraterritorial | 1990 |
| Construction Risk Consultants Limited | Professional & scientific | 2011 |
| Construction Training (Cumbria) Ltd | Other services | 2004 |
| Consultancy RTS Ltd | Education | 2012 |
| Consulting Cumbria Ltd | Information & communication | 2011 |
| Content Online Limited | Administrative & support | 2006 |
| Contract CAD Services Limited | Professional & scientific | 2003 |
| Contract Flooring (Cumbria) Limited | Construction | 1985 |
| Contract Scaffolding Services Holdings Limited | Construction | 2024 |
| Contract Scaffolding Services Limited | Construction | 1996 |
| Contrast Kitchens Limited | Manufacturing | 2006 |
| Cookie Shark Ltd | Wholesale & retail | 2023 |
| Coomara Limited | Professional & scientific | 2012 |
| Copper Rock Geological Consultants Limited | Professional & scientific | 2022 |
| Corbrund Developments Limited | Professional & scientific | 2008 |
| Corby Hill Motors Limited | Wholesale & retail | 2007 |
| Core Gym Ltd | Arts & recreation | 2014 |
| Corner Fish Shop Ltd | Hospitality | 2019 |
| Cornerstone Commerce Ltd | Wholesale & retail | 2023 |
| Cornvale Foods Limited | Wholesale & retail | 2001 |
| Corona IT Solutions Limited | Information & communication | 2020 |
| Cosmedix Limited | Health & social care | 2025 |
| Cosmetic Radiance Ltd | Health & social care | 2018 |
| Cosmic Studios CIC | Arts & recreation | 2019 |
| Costa Couriers Limited | Transport & logistics | 2010 |
| Cote House Farm | Administrative & support | 2012 |
| Country Artists Limited | Extraterritorial | 2007 |
| Country Casuals Holdings Limited | Extraterritorial | 2016 |
| Country Casuals Limited | Extraterritorial | 2016 |
| Country Gifts & Gardens Limited | Wholesale & retail | 2021 |
| Country House (Carlisle) Limited | Wholesale & retail | 2000 |
| Country House Holdings Limited | Wholesale & retail | 2021 |
| Country Style Windows Limited | Construction | 2002 |
| Countryside Business Management Limited | Professional & scientific | 2014 |
| Countryside Care & Companionship Ltd | Health & social care | 2026 |
| County Removals Limited | Transport & logistics | 2007 |
| Coupland Beck Farming | Wholesale & retail | 2026 |
| Court Yard Club Holdings Limited | Arts & recreation | 2026 |
| Court Yard Club Limited | Arts & recreation | 2026 |
| Court Yard Club Properties Limited | Arts & recreation | 2026 |
| Courts Nominees Ltd | Extraterritorial | 1998 |
| Covercall Ltd | Information & communication | 2026 |
| Cowens Limited | Manufacturing | 1999 |
| CP Engineering (Cumbria) Ltd | Professional & scientific | 2019 |