| Buttertubs Farm Limited | Agriculture & fishing | 2023 |
| Byrecroft Ltd | Construction | 2025 |
| BZS Refurbishment Ltd | Construction | 2026 |
| C & C LEE Limited | Hospitality | 2025 |
| C Clarke Management Limited | Administrative & support | 2024 |
| C S Process Contractor Limited | Construction | 2015 |
| C W Executive Properties Ltd | Real estate | 2022 |
| C W Executive Search Ltd | Administrative & support | 2019 |
| C.E.N.T.R.E. Leasing and Management Limited | Real estate | 1972 |
| C.W. Tinkler & Co. Limited | Transport & logistics | 1959 |
| Cable Investments Ltd | Real estate | 2023 |
| Cafe Mancha Ltd | Hospitality | 2025 |
| Cafe Perfection Ltd | Professional & scientific | 2002 |
| Caldercraft (1991) Limited | Manufacturing | 1988 |
| Campbell Clarence Ltd | Administrative & support | 2016 |
| Canndu Limited | Professional & scientific | 2024 |
| Caraz Limited | Other services | 2002 |
| Carebridge Cleaning Services Ltd | Administrative & support | 2026 |
| Carl Boasman Consultancy Ltd | Professional & scientific | 2024 |
| Carlite Services Limited | Transport & logistics | 2003 |
| Carlton Cars (North Yorkshire) Limited | Transport & logistics | 2003 |
| Carlton Motor Co (North East) Limited | Wholesale & retail | 2005 |
| CAS Engineering (Northallerton) Limited | Manufacturing | 2005 |
| Catmint Components Ltd | Manufacturing | 2021 |
| Cawingredients (EBT) Limited | Extraterritorial | 2016 |
| Cawingredients Limited | Manufacturing | 2008 |
| Cawlands Properties Limited | Real estate | 1965 |
| CBS Services Group Limited | Financial services | 2016 |
| CC Supplies (A&H Sales) Ltd | Wholesale & retail | 2023 |
| CE & CM Walker Limited | Administrative & support | 2009 |
| Ceallaigh Consulting Ltd | Construction | 2025 |
| Century Mortgages Limited | Professional & scientific | 1995 |
| Challenging GB Limited | Administrative & support | 2015 |
| Chamberlain Pension Trustees Limited | Administrative & support | 2004 |
| Change Working Ltd | Administrative & support | 2014 |
| Chaparral Consulting Limited | Professional & scientific | 2003 |
| Charlean Limited | Financial services | 2022 |
| Charlie Taylor Garage Services Ltd | Wholesale & retail | 2023 |
| Charnley Holdings Limited | Professional & scientific | 2006 |
| Charnley Management Limited | Real estate | 2021 |
| Charnley Marketing Limited | Wholesale & retail | 2001 |
| Charwood Properties Limited | Real estate | 2014 |
| Chatsworth Northern Limited | Construction | 2000 |
| Chimetrend Property Management Limited | Households | 1990 |
| Chris Penketh Associates Limited | Construction | 1993 |
| Chrs Energy Limited | Construction | 2025 |
| Chrs Fluid Limited | Manufacturing | 2025 |
| Chrs Holdings Limited | Financial services | 2025 |
| Church Holme Camping Limited | Hospitality | 2021 |
| CJB Business Services Ltd | Professional & scientific | 2016 |
| Clan Structures Limited | Extraterritorial | 2011 |
| Clarkes Commercials Limited | Real estate | 2018 |
| Clarkson Air CON Services Limited | Extraterritorial | 2024 |
| CLB Heritage Ltd | Professional & scientific | 2021 |
| Clean Slate Crew Ltd | Administrative & support | 2025 |
| Cleanleon Services Ltd | Administrative & support | 2024 |
| Clear Mind Psychiatry Ltd | Health & social care | 2026 |
| Clear Property Leasing Ltd | Real estate | 2026 |
| Cleenish Limited | Wholesale & retail | 2003 |
| Click Through Digital Ltd | Professional & scientific | 2014 |
| CLM Fleet Ltd | Professional & scientific | 2014 |
| Coach House & White Ltd | Professional & scientific | 2019 |
| COACH2.COM Limited | Transport & logistics | 2010 |
| Cocklewood Dairy Ltd | Extraterritorial | 2022 |
| Coffee at Number 10 (Thirsk) Limited | Hospitality | 2023 |
| Colbourn Associates Limited | Real estate | 2002 |
| Colin Hutson Accounting Limited | Professional & scientific | 2013 |
| Comet Project Management Ltd | Professional & scientific | 2021 |
| Comfort Dental Limited | Health & social care | 2015 |
| Commission an Artist Limited | Professional & scientific | 2015 |
| Competica Limited | Professional & scientific | 2001 |
| Compojure Limited | Information & communication | 2023 |
| Comstal Technology Solutions Limited | Information & communication | 2003 |
| Concept Hospitality Services Ltd | Arts & recreation | 2009 |
| Confer With Gray Ltd | Administrative & support | 2022 |
| Coniston Commercials Ltd | Wholesale & retail | 2016 |
| Considered Advice Ltd | Administrative & support | 2008 |
| Constantine Building Services Limited | Professional & scientific | 2007 |
| Constantine Contract Services Limited | Professional & scientific | 2015 |
| Contact Centre Professional Limited | Professional & scientific | 2001 |
| Contract Flooring Northallerton Limited | Other services | 2013 |
| Controlled Access 247 Ltd | Administrative & support | 2020 |
| Corporate Technology Solutions UK Ltd | Professional & scientific | 2022 |
| Corporate Trade Supplies UK Ltd | Wholesale & retail | 2020 |
| Costandi Capital Limited | Manufacturing | 2018 |
| Costandi Limited | Manufacturing | 2006 |
| Costandi Real Estates Limited | Real estate | 2019 |
| Cote Ghyll Apartments Limited | Real estate | 2022 |
| Cote Ghyll Caravan Park Limited | Hospitality | 2009 |
| Cotswold Publications Limited | Information & communication | 2010 |
| County Business Park Limited | Real estate | 2008 |
| County Flooring Contracts Limited | Construction | 2013 |
| County Town Cleaning Ltd | Administrative & support | 2015 |
| Coupland Leather Limited | Wholesale & retail | 2020 |
| Cowan Transport Limited | Transport & logistics | 2007 |
| Cowton Farming Company Limited | Agriculture & fishing | 2024 |
| Cowtons Community Enterprise Ltd | Wholesale & retail | 2017 |
| Crakehall Water Mill Limited | Hospitality | 2026 |
| Creation Estates Limited | Professional & scientific | 1998 |
| Crescent Stores Ltd | Wholesale & retail | 2023 |