| Cherry Picker Hire Ltd | Administrative & support | 2023 |
| Chez Marius Limited | Real estate | 2005 |
| Children & Family Wellbeing Services Ltd | Health & social care | 2022 |
| Chinabiz Limited | Professional & scientific | 2017 |
| Chown Group Limited | Other services | 2016 |
| Chris Foggett Ltd | Construction | 2015 |
| Chris NYE Developments Limited | Construction | 2006 |
| Christian H Miles Craft Limited | Arts & recreation | 2019 |
| Christometrics CIC | Other services | 2025 |
| Christopher Burgoyne Limited | Professional & scientific | 2002 |
| Church Financial Services Limited | Financial services | 2011 |
| Cinema Screen Logistics Ltd | Transport & logistics | 2017 |
| Cinnamon Lounge Trowbridge Private Ltd | Hospitality | 2014 |
| Cirrus Advisory Services Limited | Information & communication | 2020 |
| Civil Engineering Innovations Limited | Construction | 2012 |
| CJS Project Management Services Ltd | Information & communication | 2016 |
| Clarks Mill Management Limited | Households | 2023 |
| Classic and Modern Motorsport Club (2021) Limited | Arts & recreation | 2021 |
| Classic and Modern Motorsport Ltd | Administrative & support | 2017 |
| Clean and Supply Southwest Ltd | Wholesale & retail | 2023 |
| Clegg Associates Limited | Professional & scientific | 2002 |
| Cleveland and Gale Ltd | Construction | 2026 |
| Cleveland House Residents Limited | Households | 2017 |
| Clever FOX Consultancy Ltd | Information & communication | 2010 |
| Clifties Coffee Co Ltd | Wholesale & retail | 2025 |
| Cloud Heroes Limited | Information & communication | 2012 |
| Cloudnetic Consulting Limited | Information & communication | 2018 |
| Cloudvue Ltd | Information & communication | 2022 |
| CMA Cars Limited | Wholesale & retail | 2016 |
| Cmac Wood Machinery Ltd | Extraterritorial | 2024 |
| CMR Property Solutions Ltd | Construction | 2023 |
| Cnmb Ltd | Financial services | 2020 |
| Coaching Mindset Limited | Professional & scientific | 2013 |
| Cobham Catering Ltd | Hospitality | 2022 |
| Cockhill House Court Limited | Households | 1986 |
| Coetzer Technical Services Limited | Manufacturing | 2015 |
| Cohesion Design Ltd | Households | 2023 |
| Collaborative Schools Ltd | Education | 2012 |
| Collection House Limited | Administrative & support | 2000 |
| Collectivally Limited | Information & communication | 2025 |
| College 1957 Limited | Extraterritorial | 2013 |
| Collingwood of Somerset Limited | Manufacturing | 2019 |
| Colourcom Limited | Information & communication | 1999 |
| Columbine Communications Limited | Professional & scientific | 2017 |
| Combe GEO Services Ltd | Professional & scientific | 2023 |
| Community Learning Fellowship CIC | Education | 2022 |
| Complete Preservation Ltd | Construction | 2011 |
| Compton's Glass Workshop Ltd | Arts & recreation | 2014 |
| Computer Planning Consultants Limited | Professional & scientific | 1989 |
| Conceptuel Limited | Professional & scientific | 2016 |
| Confidence INK Limited | Other services | 2022 |
| Conley Structural Engineers Ltd | Professional & scientific | 2025 |
| Consoneo UK Ltd | Professional & scientific | 2013 |
| Constellation Procurement Limited | Professional & scientific | 2026 |
| Construction Site Scaffolding Ltd | Construction | 2005 |
| Context Cohere Consulting Limited | Professional & scientific | 2024 |
| Controltenure Property Management Limited | Real estate | 1995 |
| Convelos Solutions Limited | Financial services | 2022 |
| Convermedia Consulting Ltd | Professional & scientific | 2014 |
| Cooch Mortgages Ltd | Financial services | 2021 |
| Copand Consulting Limited | Information & communication | 2025 |
| Copper Red Design Ltd | Arts & recreation | 2017 |
| Core BRO Developments Ltd | Construction | 2026 |
| Core Construct of Bath Ltd | Construction | 2024 |
| Core Construction of Bath Ltd | Construction | 2015 |
| Cosmetic Prema Ltd | Health & social care | 2025 |
| Costello & Reyes Group Limited | Professional & scientific | 2017 |
| Coster Building Surveyors Ltd | Construction | 2025 |
| Costinbogdantransport Ltd | Transport & logistics | 2025 |
| Cottcom Limited | Construction | 2015 |
| Cottsbury Homes Limited | Construction | 2014 |
| Countrywide Building Consortium Limited | Construction | 2018 |
| County Glass & Glazing Limited | Manufacturing | 2003 |
| Court Mills Management Company Limited | Households | 2019 |
| Courtney Facilities Management Limited | Real estate | 2022 |
| Coverdek Limited | Construction | 2015 |
| COW & Gate Pension Trustees Limited | Other services | 1981 |
| Cozyco Solutions Ltd | Construction | 2024 |
| CPP Valve Limited | Real estate | 2019 |
| Crandon LEA Residents Association Limited | Households | 1984 |
| Craybourne Carpentry Limited | Construction | 2017 |
| Creo Developments CS Ltd | Construction | 2014 |
| Crescent Moon Events Limited | Arts & recreation | 2012 |
| Cresswell Bricklaying Contractors Ltd | Construction | 2023 |
| Crest Studios Limited | Information & communication | 2004 |
| Crestplus Limited | Administrative & support | 2021 |
| Croft Takeaway Limited | Hospitality | 2023 |
| Crossfit Bath LLP | | 2009 |
| Crossfit Trowbridge Limited | Arts & recreation | 2024 |
| Crossroads Therapy Limited | Health & social care | 2023 |
| CSS Plant Hire Limited | Construction | 2006 |
| CT Survey Services Ltd | Professional & scientific | 2016 |
| CTC Search Ltd | Professional & scientific | 2014 |
| Cthati Ltd | Manufacturing | 2023 |
| Cupcake Snob Ltd | Hospitality | 2025 |
| Curry Holdings Ltd | Financial services | 2026 |
| CWS Enterprises Ltd | Real estate | 2024 |
| D Propert & Sons Ltd | Construction | 2004 |
| D&G Transport Ltd | Transport & logistics | 2025 |
| D-Man Steel Services Ltd | Construction | 2025 |