| Circular Capital Limited | Energy | 2016 |
| Circular Carbon Ltd | Water & waste | 2013 |
| Circular Science Limited | Water & waste | 2013 |
| CJD Plumbing and Heating Ltd | Construction | 2016 |
| CJD Plumbing, Heating & Renewables LLP | | 2024 |
| Clacham Limited | Financial services | 1979 |
| Claire Dunford Communications Ltd | Professional & scientific | 2024 |
| Clean Energy Investments (UK) Ltd | Financial services | 2018 |
| Clean Stone Floors Ltd | Administrative & support | 2024 |
| Clements & Morris Property Group Ltd | Manufacturing | 2026 |
| Clenche Developments Limited | Construction | 2004 |
| Clenche Properties | Construction | 1985 |
| Climate Change & (In)Security Project Ltd | Professional & scientific | 2023 |
| Climate Cooling Specialists Ltd | Construction | 2025 |
| CM Agricultural Services Ltd | Agriculture & fishing | 2024 |
| Coach House Mews (Rowde) Management Company Limited | Households | 2005 |
| Coastmile Limited | Real estate | 2002 |
| Codegeist Ltd | Information & communication | 2025 |
| Coller Construction Ltd | Construction | 2022 |
| Collett Bros. Limited | Construction | 1960 |
| Commar Limited | Professional & scientific | 2002 |
| Comms Ninja Ltd | Professional & scientific | 2021 |
| Community First | Hospitality | 1983 |
| Community First Trading Limited | Financial services | 2013 |
| Comus Leisure Ltd | Hospitality | 2011 |
| Conservation Contractors Limited | Administrative & support | 2011 |
| Conservation Fencing Limited | Administrative & support | 2021 |
| Contechnicad Ltd | Construction | 2017 |
| Contemporary Collections Limited | Wholesale & retail | 2000 |
| Continuum Holdings Limited | Financial services | 2017 |
| Conyers Consulting Limited | Administrative & support | 2022 |
| Coped Hall Management Company Ltd | Real estate | 2002 |
| Coprisystems Limited | Wholesale & retail | 1989 |
| Core 2 Edge Associates Ltd | Information & communication | 2007 |
| Core Control Pilates Limited | Health & social care | 2012 |
| Corn Leaze Solar Ltd | Energy | 2015 |
| Cornbury Farm Contracting Limited | Agriculture & fishing | 2010 |
| Corsham House Limited | Hospitality | 2019 |
| Cotswold Oven Valeting Limited | Administrative & support | 2007 |
| Crackstone Clocks Limited | Other services | 2017 |
| CRE8TIVE Interiors Limited | Construction | 2011 |
| Creative by Day Ltd | Information & communication | 2020 |
| Croggan 2025 Ltd | Hospitality | 2025 |
| Crookes Services Limited | Construction | 2022 |
| Crossfit Devizes Limited | Arts & recreation | 2021 |
| Crossmolina Buildings Management Company Limited | Real estate | 2010 |
| Crossmolina Ltd | Construction | 2013 |
| Croydonbridge Limited | Real estate | 2023 |
| Crystal Clear Energy Ltd | Professional & scientific | 2025 |
| Cufflinks 4 ME (UK) Limited | Wholesale & retail | 2022 |
| Cuil Bay Capital Group Limited | Financial services | 2023 |
| Currys Motors Devizes Limited | Wholesale & retail | 2006 |
| CW Marketing Consultancy Ltd | Professional & scientific | 2020 |
| CZ Structures Ltd | Construction | 2025 |
| D & G A'Bear Farming Limited | Agriculture & fishing | 2004 |
| D C Mortimer Electrical Services Ltd | Construction | 2011 |
| D.D.P. (Trading) Limited | Other services | 1998 |
| Daaga INK Ltd | Other services | 2026 |
| Dagny Taggart Ltd | Professional & scientific | 2022 |
| Dakin Fire & Security Ltd | Administrative & support | 2021 |
| Darmill Limited | Manufacturing | 2016 |
| Darren Carter Limited | Health & social care | 2020 |
| Daryl Davies Fine Art Limited | Wholesale & retail | 2004 |
| Data Warehouse Solutions Limited | Information & communication | 2012 |
| Dauntsey's School | Education | 2006 |
| Dauntsey's School Enterprises Limited | Other services | 1994 |
| David Burns Limited | Education | 2023 |
| David JAY Associates Ltd | Administrative & support | 2017 |
| Davies-Ball Heating & Plumbing Ltd | Administrative & support | 2014 |
| Davis & Hunter Holdings Ltd | Real estate | 2024 |
| DAW Associates Limited | Wholesale & retail | 2015 |
| Dayman Limited | Transport & logistics | 1990 |
| Daytime Technology Limited | Professional & scientific | 1997 |
| DC Services (Bristol) Limited | Construction | 2011 |
| Deafenders Ltd | Health & social care | 2022 |
| Dealview Limited | Financial services | 2017 |
| Declair Ltd | Information & communication | 2021 |
| Decorative Interiors (South West) Limited | Construction | 2001 |
| Dee's Luxe Nails Limited | Other services | 2025 |
| Deep Blue Pool Management Limited | Wholesale & retail | 2002 |
| Defence IT Solutions Ltd | Information & communication | 2023 |
| Denchworth Limited | Agriculture & fishing | 2006 |
| Dennis Guiney Psychology Services Ltd | Health & social care | 2014 |
| Derby & Day Limited | Real estate | 2014 |
| Design Coefficient Limited | Professional & scientific | 1999 |
| Destinyrealm Limited | Real estate | 2002 |
| Deverson Homes Ltd | Real estate | 2025 |
| Devizes Accident Repair Centre Limited | Wholesale & retail | 2025 |
| Devizes Barber Shop Limited | Other services | 2025 |
| Devizes Books Limited | Wholesale & retail | 1998 |
| Devizes Building Supplies Limited | Wholesale & retail | 1990 |
| Devizes Community Services Ltd | Transport & logistics | 2016 |
| Devizes Control Systems (Holdings) Limited | Financial services | 2014 |
| Devizes Cranes Limited | Extraterritorial | 1994 |
| Devizes Cyber Investments Limited | Financial services | 2022 |
| Devizes Equestrian Ltd | Agriculture & fishing | 2026 |
| Devizes Fencing and Landscaping Ltd | Wholesale & retail | 2015 |
| Devizes Hand Car Wash Ltd | Wholesale & retail | 2026 |
| Devizes Hire Limited | Extraterritorial | 2004 |
| Devizes Motor Services Ltd | Wholesale & retail | 2024 |