| Cafeamsterdam Limited | Hospitality | 2024 |
| Caffe DI Bella Limited | Hospitality | 2016 |
| CAG Holdings Limited | Mining & quarrying | 2016 |
| Calcore Electrical Limited | Construction | 2025 |
| Call Joe.Co.Uk Limited | Construction | 2016 |
| Callas Property Limited | Real estate | 2025 |
| Callum Stuart Logistics Limited | Transport & logistics | 2025 |
| Candy Creation’S Whitley Bay Ltd | Wholesale & retail | 2023 |
| Candy White Limited | Extraterritorial | 2014 |
| Capello Hair Salon Limited | Other services | 2015 |
| Capstan Court Limited | Households | 2001 |
| Caravan Source Ltd | Transport & logistics | 2021 |
| Carbon Internet Ltd | Information & communication | 2018 |
| Cardehar & Co (UK) LLP | | 2013 |
| Cardehar & Co Limited | Professional & scientific | 2007 |
| Cardehar Limited | Administrative & support | 2006 |
| Carerflare Ltd | Other services | 2018 |
| Carl and Samantha Leisure Limited | Hospitality | 2017 |
| Carnelian Accountancy Limited | Professional & scientific | 2015 |
| Carney Consultancy Holdings Limited | Financial services | 2022 |
| Carney Consultancy Ltd | Health & social care | 2002 |
| Carole Crowe Interior Design Ltd | Professional & scientific | 2022 |
| Carr and Cawson Housing Consultants Ltd | Professional & scientific | 2017 |
| Carr Fleet Solutions Limited | Wholesale & retail | 2023 |
| Carrie Cook Consulting Ltd | Professional & scientific | 2023 |
| Casa-Hat Limited | Real estate | 2024 |
| Cass Barbers Ltd | Other services | 2023 |
| Castaways Tea Shop Limited | Hospitality | 2019 |
| Castledene Wholesale Ltd | Wholesale & retail | 2011 |
| Catalyst Health Ltd | Professional & scientific | 2024 |
| Catbells Business Solutions Ltd | Professional & scientific | 2021 |
| Caterpak Limited | Wholesale & retail | 2005 |
| Catherine Sargent Coaching Ltd | Health & social care | 2024 |
| Causeway Consulting Ltd | Professional & scientific | 2022 |
| Causey House (Gosforth) Management Company Limited | Households | 2013 |
| Caveys Patch Limited | Wholesale & retail | 2023 |
| Cazoobi Limited | Information & communication | 2014 |
| CBF Electrical Ltd | Construction | 2019 |
| CDL Tools Limited | Wholesale & retail | 2025 |
| Cedar Property & Management Limited | Hospitality | 2018 |
| Cedar Property Maintenance Limited | Real estate | 2005 |
| Centric Consultants Limited | Professional & scientific | 2021 |
| Centricity Group Ltd | Administrative & support | 2025 |
| Centro Connect Limited | Information & communication | 2013 |
| CF More Limited | Arts & recreation | 2014 |
| Chang Jian Limited | Hospitality | 2013 |
| Charlie Cane Engineering Services Limited | Administrative & support | 2007 |
| Charlie Gates Tattoo Limited | Other services | 2025 |
| Chasm Management Limited | Real estate | 2024 |
| Chatmint Ltd | Information & communication | 2025 |
| Cheldon Consultants Limited | Professional & scientific | 2022 |
| Cheviot Investments Limited | Construction | 2019 |
| Chick Pizz NE Ltd | Hospitality | 2023 |
| Chill OUT Time Childcare Ltd | Education | 2018 |
| CHJ Investments Ltd | Administrative & support | 2013 |
| Chris Bogle Films Limited | Information & communication | 2007 |
| Christina Gates Ltd | Professional & scientific | 2015 |
| Christine Oxenburgh Limited | Professional & scientific | 2016 |
| Ciara Langtry Sport Psychology Ltd | Arts & recreation | 2024 |
| Circuit Vehicle Deliveries Limited | Transport & logistics | 2018 |
| Citygate Apartments Management Limited | Real estate | 2002 |
| Civinet Associates Limited | Professional & scientific | 2024 |
| Civinet Ltd | Information & communication | 2012 |
| CJW Country Property Limited | Professional & scientific | 2012 |
| CKP Management Co Limited | Households | 2022 |
| Claire Rivers Ltd | Education | 2024 |
| Clara Aesthetics Limited | Other services | 2023 |
| Clare Heffernan Architecture & Design Limited | Professional & scientific | 2014 |
| Claremont Bakery Retail Ltd | Wholesale & retail | 2021 |
| Claremontrad Limited | Professional & scientific | 2010 |
| Clarence and Waterford Crescent Residents Association Limited | Other services | 2011 |
| Clark Residential Limited | Construction | 2003 |
| Clean Stays North East Limited | Administrative & support | 2024 |
| Clearlite Rooflight Co. Limited | | 1972 |
| Clearview Graphics Ltd | Manufacturing | 2022 |
| Cleva Charge Limited | Administrative & support | 2026 |
| Cliftonville Properties Ltd | Real estate | 2025 |
| Climate Conscious Bristol Ltd | Professional & scientific | 2025 |
| Clothier Lacey & Co Limited | Administrative & support | 2005 |
| Cloud 7 Developments Ltd | Construction | 2021 |
| Cloudsparker Ltd | Information & communication | 2020 |
| Club Amusements Holdings Limited | Financial services | 2018 |
| Club Amusements Limited | Administrative & support | 2011 |
| Club Havana WB Ltd | Hospitality | 2022 |
| Clusters Bespoke Jewellery Limited | Wholesale & retail | 2001 |
| Cmlw Consulting Ltd | Information & communication | 2016 |
| Coast Associates Ltd | Professional & scientific | 2024 |
| Coast Hospitality Limited | Hospitality | 2024 |
| Coastline Office Furniture Ltd | Wholesale & retail | 2005 |
| Coastline Properties Limited | Real estate | 1989 |
| Cobalt Fitness Ltd | Arts & recreation | 2016 |
| Cocoa Joe's (York) Limited | Manufacturing | 2020 |
| Cocoa Joe's Limited | Wholesale & retail | 2018 |
| Cocomo Properties Limited | Real estate | 2024 |
| Cocoon Music CIC | Education | 2025 |
| Codepro Software Ltd | Information & communication | 2025 |
| Coe-Habitation Ltd | Real estate | 2020 |
| Cogiva Limited | Information & communication | 2008 |
| Collab Staff Solutions Ltd | Administrative & support | 2025 |
| Collingwood Construction Services Limited | Construction | 2018 |