| Coachtec Ltd | Wholesale & retail | 2009 |
| Coalesce Communications Ltd | Administrative & support | 2023 |
| Coalton Ltd | Hospitality | 2001 |
| Coan Venture Management Limited | Real estate | 2011 |
| Coast & County Property Management (Yorkshire) Ltd | Real estate | 2020 |
| Coast to Coast Networks LLP | | 2026 |
| Coast to Coast Recycling Limited | Water & waste | 2005 |
| Coast to Coast Residential Limited | Hospitality | 2010 |
| Coastal Coaches Ltd | Transport & logistics | 2010 |
| Coastal Dunes (Lytham ST Annes) Management Company Limited | Households | 2015 |
| Coastal, Marine & Estuarine Habitat and Wildlife Alliance CIC | Wholesale & retail | 2025 |
| Coastway (Hove) Limited | Professional & scientific | 1999 |
| Coates Finance Limited | Financial services | 2018 |
| Coatglade Limited | Extraterritorial | 1969 |
| Coatmakers of York Ltd | Manufacturing | 2019 |
| Coats on Clothing Ltd | Wholesale & retail | 2025 |
| Cobalt Blue Water Consultancy Ltd | Professional & scientific | 2022 |
| Cobb Renovations Limited | Construction | 2025 |
| Cobblestone Developments Limited | Construction | 1985 |
| Cobblestone Projects Ltd | Other services | 2013 |
| Cobo YE Dental Practice Limited | Health & social care | 2011 |
| Cock and Bottle (2016 Ltd | Administrative & support | 2016 |
| Cockpit Land Ltd | Agriculture & fishing | 2014 |
| Coddiwomple's Rest Limited | Hospitality | 2026 |
| Codefocus Limited | Information & communication | 2024 |
| Codemix Ltd | Information & communication | 2013 |
| Codestern Ltd | Information & communication | 2026 |
| Codop Ltd | Information & communication | 2013 |
| Coed Darcy (Llandarcy) Management Company Limited | Households | 2013 |
| Coen Property Holdings Limited | Real estate | 2024 |
| Coeva Advisory Ltd | Professional & scientific | 2026 |
| Coffee Cake Create Cafe Ltd | Hospitality | 2018 |
| Cogent Consultancy Services Ltd | Professional & scientific | 2019 |
| Cognitio Services Limited | Education | 2021 |
| Cognivert Ltd | Information & communication | 2026 |
| Cognovamx Ltd | Information & communication | 2026 |
| Coherent Quantum Ltd | Professional & scientific | 2021 |
| Coho Limited | Professional & scientific | 2004 |
| Coidan Graphite Products Limited | Wholesale & retail | 2004 |
| Cojac Construction Ltd | Construction | 2026 |
| Colbaran Limited | Wholesale & retail | 2012 |
| Colburn Management Company Limited | Extraterritorial | 1988 |
| Cole Todd Fabrication Ltd | Manufacturing | 2025 |
| Cole's Gallery Limited | Wholesale & retail | 2019 |
| Colenso Commercial Agency Limited | Real estate | 2024 |
| Colenso Holdings Limited | Financial services | 2017 |
| Colette Brown Limited | Professional & scientific | 2025 |
| Colgrave Buxton Limited | Professional & scientific | 2014 |
| Colin Bell & SON Plumbing & Heating Ltd | Construction | 2024 |
| Colin Dinnie Solutions Ltd | Professional & scientific | 2016 |
| Collab-Ed LLP | | 2016 |
| Collaborative Interventions Ltd | Administrative & support | 2018 |
| Collage International Limited | Administrative & support | 2003 |
| Collected Property Limited | Real estate | 2020 |
| Collective Events Ltd | Arts & recreation | 2020 |
| College Park (Thurston) Residents Management Company Limited | Households | 2020 |
| Collette Andrew Ltd | Manufacturing | 2022 |
| Colley Investments Holdings Limited | Financial services | 2021 |
| Collier Medical Services Limited | Health & social care | 2013 |
| Collier Plant Hire (York) Limited | Construction | 1979 |
| Colliergate Ltd | Real estate | 2024 |
| Collin Advisors Limited | Professional & scientific | 2011 |
| Colling Investments Ltd | Financial services | 2024 |
| Collings Property Ltd | Real estate | 2024 |
| Collosuss Ltd | Wholesale & retail | 2017 |
| Colman's of Stamford Bridge Ltd | Real estate | 2022 |
| Colmworth Electronics Limited | Manufacturing | 1991 |
| Colonia Developments Ltd | Professional & scientific | 2018 |
| Colonial Wharf (Chatham) Residents Management Company Limited | Households | 2019 |
| Colorday Limited | Hospitality | 2017 |
| Colour Crazy Resprays Limited | Wholesale & retail | 2008 |
| Colour Heroes Limited | Information & communication | 2001 |
| Colour History Limited | Professional & scientific | 2004 |
| Colour Worx York Ltd | Wholesale & retail | 2017 |
| Colourscape Investments Limited | Health & social care | 1982 |
| Colton Conveyancing Limited | Professional & scientific | 2023 |
| Comben Group Limited | Extraterritorial | 1924 |
| Comber Consultancy Limited | Health & social care | 2015 |
| Come on Productions Limited | Extraterritorial | 2012 |
| Come What MAY Life CIC | Education | 2026 |
| Comealive-Media Ltd | Information & communication | 2014 |
| Commercial Chimney Sweeping Ltd | Administrative & support | 2016 |
| Commercial Interior Contracts Limited | Construction | 2000 |
| Commercial Refinishing UK Limited | Wholesale & retail | 2023 |
| Commercial Technology Limited | Information & communication | 1985 |
| Common Cause Group Ltd | Extraterritorial | 2026 |
| Common Threads Community Ltd | Information & communication | 2025 |
| Commonwealth Labs Ltd | Professional & scientific | 2024 |
| Community Bees CIC | Other services | 2019 |
| Community Brewers Ltd | Hospitality | 2011 |
| Community First Yorkshire Ltd | Information & communication | 1984 |
| Community Furniture Store (Ryedale) Limited | Wholesale & retail | 2013 |
| Community Furniture Store (Selby) Ltd | Wholesale & retail | 2006 |
| Community Furniture Store (York) Ltd | Wholesale & retail | 2006 |
| Community Furniture Stores Trading Ltd | Wholesale & retail | 2025 |
| Community Intelligence Europe Limited | Professional & scientific | 1992 |
| Community UK Limited | Wholesale & retail | 2005 |
| Compact Camper Conversions Limited | Manufacturing | 1999 |
| Companion Financial Planning LLP | | 2013 |
| Compass BC Property Limited | Real estate | 2017 |