| Clinikare Ltd | Administrative & support | 2021 |
| Clinportal Limited | Information & communication | 2017 |
| Clint Limited | Financial services | 2008 |
| Clockhouse Cotford Management Limited | Households | 2015 |
| Clothes to Go Limited | Wholesale & retail | 2011 |
| Cloudfortyseven Limited | Information & communication | 2009 |
| Clover House Dental Practice Ltd | Health & social care | 2008 |
| Clover Landscapes Limited | Administrative & support | 2005 |
| CLP SW Engineering Ltd | Extraterritorial | 2017 |
| CLS Electrical (SW) Ltd | Construction | 2023 |
| Club Utopia Ltd | Hospitality | 2024 |
| Clubnest Ltd | Information & communication | 2026 |
| Cluff Property Management Ltd | Real estate | 1998 |
| Clune Properties Limited | Professional & scientific | 2001 |
| CM Geomatics Limited | Professional & scientific | 2019 |
| CM Infinity Estates Limited | Real estate | 2015 |
| CMC Global Consulting Limited | Professional & scientific | 2011 |
| CML Multi Management Limited | Professional & scientific | 2009 |
| Cmwv Ltd | Professional & scientific | 2022 |
| Cmwv Property Limited | Real estate | 2023 |
| CNC Advisory Limited | Professional & scientific | 2016 |
| Cncptclo Ltd | Wholesale & retail | 2024 |
| CNV Property Ltd | Real estate | 2022 |
| Co-Creative Design Ltd | Arts & recreation | 2014 |
| Co-Formation Group Limited | Health & social care | 2020 |
| Co-Formation Ltd | Professional & scientific | 2017 |
| Co-Op International Ltd | Administrative & support | 2008 |
| CO2 Solutions Ltd | Professional & scientific | 2019 |
| Coach Candor Ltd | Professional & scientific | 2024 |
| Coast & Country Parks Limited | Hospitality | 2019 |
| Coast and Vale Limited | Wholesale & retail | 2014 |
| Coastal Asphalts Limited | Construction | 2008 |
| Coastal Drywall Ltd | Construction | 2006 |
| Coates Investments Limited | Real estate | 2018 |
| Cobh Developments Limited | Construction | 2001 |
| Cobhay Limited | Professional & scientific | 2010 |
| Cobley Investments Limited | Financial services | 2024 |
| Cockwood Fabrication Limited | Manufacturing | 2005 |
| Coco Blue Somerset Limited | Wholesale & retail | 2008 |
| Cocreative Future Ltd | Professional & scientific | 2024 |
| Codana Properties Ltd | Real estate | 2024 |
| Codeblock Labs Ltd | Information & communication | 2024 |
| Codeglove Limited | Information & communication | 2010 |
| Coditorium Ltd | Information & communication | 2018 |
| Coffee 212 Limited | Extraterritorial | 2013 |
| Coffee Blue Somerset West and Taunton Ltd | Hospitality | 2021 |
| Coffee House Productions Ltd | Information & communication | 2024 |
| Coffee,Chat & Support CIC | Administrative & support | 2024 |
| Cogent Planning Ltd | Financial services | 2013 |
| Cogent Research Ltd | Financial services | 2003 |
| Cogswell Black Limited | Health & social care | 2025 |
| Coker Construction Limited | Construction | 2017 |
| Coker Engineering Limited | Manufacturing | 1993 |
| Coker Holdings Limited | Financial services | 2017 |
| Coker View Management Company Limited | Households | 1983 |
| Cokerest Limited | Administrative & support | 2006 |
| Colbil Limited | Real estate | 2023 |
| Cole Wealth Management Ltd | Professional & scientific | 2021 |
| Colebrooke Cleansing Ltd | Water & waste | 2024 |
| Colecom Ltd | Wholesale & retail | 2024 |
| Coleman Plumbing & Heating Limited | Construction | 2014 |
| Coleman Removals Ltd | Transport & logistics | 2012 |
| Coleman Storage Limited | Transport & logistics | 2016 |
| Coles Commercials Limited | Wholesale & retail | 2007 |
| Coles Engineering Limited | Wholesale & retail | 1998 |
| Coles Fire Systems Limited | Public administration | 2016 |
| Colin Merrick Limited | Construction | 2004 |
| Colin Stephens Contractor Limited | Construction | 2014 |
| Colinez Property Ltd | Real estate | 2025 |
| Collaborate 4 Change Limited | Health & social care | 2015 |
| Collaborative Solutions Consulting and Psychology Services Ltd | Professional & scientific | 2023 |
| Collier Planning Limited | Professional & scientific | 2015 |
| Collier Property Ltd | Real estate | 2024 |
| Collingwood Residents Management Company Limited | Households | 2011 |
| Collipriest H0USE Management C0MPANY Limited | Households | 1980 |
| Colliton Barton Limited | Agriculture & fishing | 2010 |
| Collonnades Limited | Wholesale & retail | 2008 |
| Colmar Construction (Poole) Limited | Construction | 2011 |
| Colour Coded Decorators Limited | Construction | 2015 |
| Colour Coded Sealants Ltd | Construction | 2026 |
| Colour Conscious Clothing Limited | Wholesale & retail | 2016 |
| Colwyn Contracting Limited | Agriculture & fishing | 2025 |
| Coman Delivery Ltd | Transport & logistics | 2019 |
| Combers Limited | Other services | 2004 |
| Combined Electrical Services Limited | Construction | 2017 |
| Come to Quilt Limited | Wholesale & retail | 2024 |
| Comely Colours Ltd | Wholesale & retail | 2025 |
| Comely Ltd | Hospitality | 2019 |
| Comeytrowe Security Trustee Limited | Extraterritorial | 2019 |
| Commercial Mortgage Group Limited | Financial services | 2006 |
| Community Pain Hubs Somerset CIC | Health & social care | 2025 |
| Compact Access Limited | Professional & scientific | 2015 |
| Compact Foilers Ltd | Extraterritorial | 2009 |
| Compass Agri (Holdings) Limited | Financial services | 2017 |
| Compass Apartments Limited | Households | 2009 |
| Compass Construction Limited | Construction | 2003 |
| Compass Disability Services | Other services | 2001 |
| Compass Leading Limited | Professional & scientific | 2023 |
| Compass Point (Taunton) Management Company Limited | Households | 2008 |
| Compass Rise Management Company Limited | Households | 1978 |