| Byte Science Ltd | Real estate | 2003 |
| C & a Wood Limited | Real estate | 2016 |
| C & C Facilities Ltd | Construction | 2019 |
| C & G Group Limited | Construction | 2016 |
| C & G Motors Limited | Wholesale & retail | 2011 |
| C & G Property Management Limited | Real estate | 2009 |
| C & L Wholecrafts Ltd | Wholesale & retail | 2023 |
| C & M Auto Services Ltd | Wholesale & retail | 2008 |
| C & M B Leasing Limited | Administrative & support | 1979 |
| C & M Denness Limited | Agriculture & fishing | 2001 |
| C & M Properties (York) Limited | Real estate | 2025 |
| C & N Hobson Limited | Agriculture & fishing | 1991 |
| C & P Painting and Decorating Ltd | Construction | 2022 |
| C & R Homes Ltd | Real estate | 2022 |
| C & T Medics Limited | Health & social care | 2020 |
| C and E Sales Ltd | Wholesale & retail | 2025 |
| C and M (York) Ltd | Hospitality | 2020 |
| C C Union Ltd | Real estate | 2023 |
| C G Properties (York) Limited | Real estate | 2011 |
| C H Stephenson & Sons Limited | Agriculture & fishing | 2003 |
| C J Cook Limited | Construction | 2006 |
| C J Vize Ltd | Health & social care | 2011 |
| C Jacob Limited | Health & social care | 2025 |
| C K Safety Limited | Manufacturing | 1992 |
| C M Jacob Limited | Information & communication | 2026 |
| C M Lettings Ltd | Real estate | 1998 |
| C My Colour Limited | Information & communication | 2019 |
| C Prangnell Plasterers Ltd | Construction | 2025 |
| C R & C L Donaldson Ltd | Agriculture & fishing | 2008 |
| C R Leiby Ltd | Information & communication | 1999 |
| C S Fenton & Co Ltd | Professional & scientific | 2023 |
| C Stone Developments Ltd | Construction | 2021 |
| C W Scholey Farming Ltd | Agriculture & fishing | 2018 |
| C W Strickland & SON Ltd | Manufacturing | 2002 |
| C&J Buyers Ltd | Wholesale & retail | 2022 |
| C&K Pizza Limited | Hospitality | 2018 |
| C&L Monaco Ltd | Construction | 2023 |
| C&M Lettings York Ltd | Real estate | 2023 |
| C&M Travel Ltd | Transport & logistics | 2025 |
| C&R Landscapes Limited | Administrative & support | 2019 |
| C&Rs York Limited | Wholesale & retail | 2014 |
| C&S Lockwood Limited | Wholesale & retail | 2024 |
| C&S Sandwich Ltd | Wholesale & retail | 2022 |
| C. S. Snowdon Ltd | Agriculture & fishing | 2013 |
| C.A.S Rail Ltd | Professional & scientific | 2023 |
| C.G. Kendall Limited | Agriculture & fishing | 2016 |
| C.S.K. Developments Limited | Real estate | 1997 |
| C.T.Hobson Limited | Agriculture & fishing | 2026 |
| C2 (North East) Ltd | Administrative & support | 2019 |
| C2 Project Safety Ltd | Administrative & support | 2014 |
| C4DI Ventures Limited | Information & communication | 2013 |
| CA Scaffolding Ltd | Construction | 2026 |
| CA Signalling Ltd | Professional & scientific | 2021 |
| CA Wilson Ltd | Real estate | 2024 |
| CAB Independent Health Consultancy Ltd | Health & social care | 2019 |
| CAB Investments Limited | Real estate | 2018 |
| Cabbage and Plum Ltd | Professional & scientific | 2024 |
| Cabbaw Ltd | Real estate | 2019 |
| Cabinlocator Holdings Limited | Financial services | 2022 |
| Cabinlocator Limited | Manufacturing | 2010 |
| Cablelink Leeds Limited | Construction | 2011 |
| Caboodle York Limited | Wholesale & retail | 2014 |
| Cabtech Joinery Ltd | Construction | 2011 |
| Cadbury Estates Limited | Real estate | 2007 |
| Caddick (York) Management Company Limited | Households | 2006 |
| Caddie Couture Ltd | Wholesale & retail | 2024 |
| Cadence Coffee Roasters Limited | Manufacturing | 2023 |
| Cads Tech Ltd | Professional & scientific | 2019 |
| Caedmon Homes (York ) Ltd | Real estate | 2021 |
| Caeledro Consulting Ltd | Education | 2021 |
| Caerlee Ltd | Wholesale & retail | 2026 |
| Caerphilly Veterinary Clinic Limited | Professional & scientific | 2010 |
| Caesar of Carlton Limited | Real estate | 2021 |
| Caesars at the Minster Ltd | Hospitality | 2024 |
| Cafe 4 Limited | Hospitality | 2025 |
| Cafe 88 Ltd | Hospitality | 2025 |
| Cafe at NO 12 Ltd | Hospitality | 2025 |
| Cafe Fleur York Ltd | Hospitality | 2022 |
| Cafe Jinnah LLP | | 2014 |
| Café Frango (Haxby Road) Limited | Hospitality | 2024 |
| Café Racer Yorkshire Limited | Hospitality | 2019 |
| Cail Trade & Invest Ltd | Wholesale & retail | 2018 |
| Cain Decorators Ltd | Construction | 2019 |
| Caittom Consultancy Limited | Professional & scientific | 2022 |
| CAJ Property Limited | Real estate | 2025 |
| Cake Fairy Yorkshire Ltd. | Manufacturing | 2018 |
| Calcaria Veterinary Practice Ltd | Professional & scientific | 2004 |
| Calcination Ltd | Wholesale & retail | 2021 |
| Calderdale Developments Limited | Construction | 1994 |
| Caledonia Consulting Limited | Professional & scientific | 2010 |
| Caledonia Foods Limited | Hospitality | 2005 |
| Caledonia Swim School LLP | | 2024 |
| Calibrated Geoscience UK Ltd. | Mining & quarrying | 2018 |
| Calibre Property Services Limited | Construction | 2019 |
| Call IT Support Limited | Information & communication | 2022 |
| Calldon Limited | Extraterritorial | 2012 |
| Callers-Linden Holdings Limited | Hospitality | 1995 |
| Callingworth Gray Limited | Professional & scientific | 2019 |
| Callipygian Code Ltd. | Information & communication | 2015 |
| Callum Electrichall Ltd | Construction | 2021 |