| Celli International Limited | Financial services | 2013 |
| Cellier Holdings Ltd | Financial services | 2021 |
| Centre for Health and Pastoral Care | Health & social care | 2003 |
| CF AG Hire Ltd | Administrative & support | 2026 |
| CGR Sports Advisory Limited | Professional & scientific | 2026 |
| Charlie George Limited | Information & communication | 2018 |
| Chicken Chaser Motorcycles Ltd | Wholesale & retail | 2024 |
| Chococart Limited | Wholesale & retail | 2025 |
| Chorality Ltd | Information & communication | 2011 |
| Church Gate (York) Management Company Limited | Households | 2008 |
| Churchill Mews (Dalton) Management Company Limited | Households | 2019 |
| Cigma Ltd | Information & communication | 2017 |
| Citie Cleaning Services Limited | Administrative & support | 2002 |
| City Healthcare Direct Limited | Other services | 2005 |
| CJT Earthworks Ltd | Construction | 2024 |
| Cleaboy Farms Company | Agriculture & fishing | 1962 |
| Clear Call Agency Ltd | Professional & scientific | 2019 |
| Cleveland Partitions Ltd | Construction | 2025 |
| Cliffestones Properties Limited | Construction | 2018 |
| Club Customz Limited | Wholesale & retail | 2022 |
| CM Unit Cars Ltd | Transport & logistics | 2025 |
| CM90 Limited | Professional & scientific | 2014 |
| Coclens Limited | Manufacturing | 2021 |
| COD Beck Blenders Limited | Manufacturing | 1988 |
| Coffee & Plans (UK) Limited | Information & communication | 2015 |
| Colin Potter Farms Limited | Agriculture & fishing | 1977 |
| Collective Green Energy (Yorkshire ) Limited | Wholesale & retail | 2017 |
| Collective Green EOT Limited | Financial services | 2025 |
| Comfy Nooks Ltd | Real estate | 2025 |
| Compact Engineering Limited | Manufacturing | 1986 |
| Companion Cleaning Services Ltd | Administrative & support | 2024 |
| Compos Mentis Administration Services Limited | Professional & scientific | 2014 |
| Connection Training Equine Ltd | Education | 2017 |
| Coral & Crown Ltd | Professional & scientific | 2024 |
| Cordwell's Concepts Ltd | Professional & scientific | 2025 |
| Cormin Limited | Mining & quarrying | 2022 |
| Corner Engineering Limited | Professional & scientific | 2014 |
| Crabtroncmaster Ltd | Hospitality | 2024 |
| Crakehill Poultry Limited | Agriculture & fishing | 2022 |
| Croft Pottery Ltd | Education | 2025 |
| Crofter's Foods Limited | Wholesale & retail | 2005 |
| Crofter's Foods Trustee Limited | Financial services | 2024 |
| Croptech Limited | Administrative & support | 1998 |
| Crosslands Hill Farming Company Limited | Agriculture & fishing | 1996 |
| Crown and Anchor Kitchen Ltd | Hospitality | 2025 |
| Crown Chains Limited | Manufacturing | 2017 |
| Crushing and Screening Limited | Manufacturing | 2005 |
| Cummins Estate Management Ltd | Real estate | 2023 |
| Cyrrus (Holdings) Limited | Professional & scientific | 2009 |
| Cyrrus (Products) Limited | Professional & scientific | 2009 |
| Cyrrus (Projects) Limited | Professional & scientific | 2009 |
| Cyrrus Air Traffic Services Ltd | Transport & logistics | 2024 |
| Cyrrus Limited | Professional & scientific | 2007 |
| D & L Concepts LLP | | 2011 |
| D & M Rumbold Ltd | Construction | 2011 |
| D. O’Leary Haulage Limited | Transport & logistics | 2025 |
| D.J.D Scaffolding Ltd | Construction | 2019 |
| DA Silva Group Ltd | Financial services | 2024 |
| DA Silva Property Ltd | Hospitality | 2024 |
| Dair Development Group Ltd | Financial services | 2025 |
| Dale's Auto Services Ltd | Wholesale & retail | 2025 |
| Dalefoot Holdings Ltd | Financial services | 2025 |
| Dalefoot Leisure Ltd | Hospitality | 2025 |
| Dalesway Limited | Real estate | 1979 |
| Dalton Bidco Limited | Financial services | 2020 |
| Dalton Bridge Park Limited | Real estate | 2021 |
| Dalton Euro Holdco Limited | Financial services | 2025 |
| Dalton Holdco Limited | Financial services | 2020 |
| Dalton Intermediate Holdco Limited | Financial services | 2020 |
| Dalton Midco Limited | Financial services | 2020 |
| Dalton Motors (Thirsk) Limited | Agriculture & fishing | 1975 |
| Dalton Topco Limited | Financial services | 2020 |
| Damian James Limited | Other services | 2005 |
| DAN Clark Services Ltd | Wholesale & retail | 2020 |
| Daniel Burdett Limited | Information & communication | 2013 |
| Daracott Estates Limited | Health & social care | 2005 |
| Darbyshire & Carter Properties Limited | Hospitality | 2019 |
| David Moody Limited | Professional & scientific | 2008 |
| Davis Lund Ltd | Real estate | 2020 |
| DC & VC Property Limited | Real estate | 2023 |
| DC Lift Installations Limited | Manufacturing | 2013 |
| DCD Teamwear Ltd | Wholesale & retail | 2022 |
| DD Electrical and Security Limited | Construction | 2012 |
| Dd&Pl Ltd | Hospitality | 2024 |
| DE Mowbray Care Homes Limited | Health & social care | 1995 |
| DE Mowbray Courtyard Management Limited | Real estate | 2021 |
| DE Mowbray Music Ltd | Information & communication | 2021 |
| Decosemo Solutions Limited | Administrative & support | 2007 |
| Delmere Investments Limited | Financial services | 2014 |
| Delta Alpha Safety Limited | Information & communication | 2018 |
| Denmarks Select Cars Ltd | Wholesale & retail | 2022 |
| Dependable Productions Limited | Information & communication | 2009 |
| Deram Ltd | Real estate | 2021 |
| Design Bifolds Ltd | Construction | 2023 |
| Design Display Ltd | Manufacturing | 2018 |
| Desirable Direct Limited | Wholesale & retail | 2025 |
| Dexter Socii Ltd | Professional & scientific | 2026 |
| Diligence Projects Ltd | Education | 2019 |
| Direct Publications Limited | Information & communication | 2009 |
| Discus Business Services Limited | Professional & scientific | 2008 |