| Byron Hospitality Ltd | Hospitality | 2024 |
| Byte Sky Games Ltd | Information & communication | 2023 |
| C & C Fibreglass Ltd | Manufacturing | 2014 |
| C & I Consultancy Ltd | Administrative & support | 2025 |
| C & J Designs Limited | Professional & scientific | 2013 |
| C & L Shelley Limited | Professional & scientific | 1999 |
| C & T Fresh to Home Limited | Wholesale & retail | 2024 |
| C a Guymer Plumbing and Heating Ltd | Construction | 2024 |
| C C Contractors Limited | Agriculture & fishing | 2002 |
| C Cartwright Drylining Ltd | Construction | 2022 |
| C Collen Consulting Ltd | Professional & scientific | 2024 |
| C G Newell Ltd | Construction | 2014 |
| C J Canvas Art Limited | Wholesale & retail | 2025 |
| C J Conversions Limited | Manufacturing | 2003 |
| C J Lovett Limited | Professional & scientific | 2019 |
| C J Pemberton Limited | Real estate | 2016 |
| C Kastner Medical Ltd | Health & social care | 2012 |
| C Key Limited | Real estate | 2007 |
| C M Construction and Developments Limited | Construction | 2017 |
| C N Overton Holdings Limited | Financial services | 2012 |
| C R Moss Property Maintenance Limited | Construction | 2011 |
| C R Properties (Lincoln) Limited | Real estate | 2017 |
| C R Sheldon Limited | Financial services | 2025 |
| C S Building & Brickwork Ltd | Construction | 2018 |
| C S I Medical Consultancy Ltd | Health & social care | 2015 |
| C W Spence Management Limited | Real estate | 2015 |
| C Williams & Sons Limited | Construction | 2008 |
| C&E Deliveries Limited | Transport & logistics | 2024 |
| C&E Safety Consultants Limited | Professional & scientific | 2013 |
| C&H Invetsments Ltd | Financial services | 2024 |
| C&Kh Ltd | Real estate | 2025 |
| C. L. Bembridge Limited | Agriculture & fishing | 1951 |
| C.A.S. Communications Ltd | Information & communication | 2012 |
| C.A.S. Telecommunications Limited | Information & communication | 2006 |
| C.F.Banks Limited | Agriculture & fishing | 1962 |
| C.H.C Electrical Ltd | Construction | 2021 |
| C.J.Sherwood Contracting Ltd | Administrative & support | 2018 |
| C.N. Overton Limited | Agriculture & fishing | 1974 |
| C.R.A.B. Lets Ltd | Real estate | 2025 |
| C.Tomlinson Limited | Agriculture & fishing | 1959 |
| C1 Media Ltd | Education | 2008 |
| C2 Boilers Limited | Construction | 2025 |
| C3D Holdings Ltd | Manufacturing | 2024 |
| CA Automotive Ltd | Wholesale & retail | 2026 |
| Cabbyon Ltd | Transport & logistics | 2024 |
| Cabello Hair Lounge Ltd | Other services | 2023 |
| Cable Telecommunications Training Services Limited | Information & communication | 1995 |
| Cablecycle Limited | Wholesale & retail | 2005 |
| CABS4LESS Ltd | Transport & logistics | 2011 |
| Cabserve Limited | Wholesale & retail | 2006 |
| Cabss Innovations Limited | Manufacturing | 2024 |
| Cadence Business Services Ltd | Information & communication | 2019 |
| Cadland Properties Limited | Real estate | 2004 |
| Cafe 81 (Bircotes) Limited | Hospitality | 2024 |
| Caffe Portico Limited | Hospitality | 2023 |
| Cahoots (Lincoln) Limited | Wholesale & retail | 2002 |
| Cahoots for MEN Limited | Wholesale & retail | 2018 |
| Cairene Limited | Information & communication | 2014 |
| Calc Estates Limited | Real estate | 2026 |
| Calceus Innovations and Solutions Ltd | Professional & scientific | 2018 |
| CALCUL8 Limited | Professional & scientific | 2011 |
| Caldo Limited | Hospitality | 2023 |
| Calibre Conservation Ltd | Financial services | 2017 |
| Call MR FIX IT Limited | Other services | 2025 |
| Callans Investments Ltd | Real estate | 2016 |
| Callow Retail Ltd | Wholesale & retail | 2011 |
| Camalot Limited | Real estate | 2018 |
| Camamile Limited | Administrative & support | 2011 |
| Camamile Partners Limited | Administrative & support | 2009 |
| Cambia Projects Ltd | Professional & scientific | 2018 |
| Cambridge Chest Meetings | Health & social care | 2018 |
| Cambridge Clinical Imaging Ltd | Health & social care | 2014 |
| Cambridge EYE Consultant Ltd | Health & social care | 2019 |
| Cambridge EYE Specialists LLP | | 2015 |
| Cambridge Infection Diagnostics Ltd | Professional & scientific | 2020 |
| Cambridge Specialist EYE Centre Ltd | Health & social care | 2015 |
| Cambridge Vision Ltd | Health & social care | 2023 |
| Camli Care Ltd | Health & social care | 2018 |
| Camluks Ltd | Health & social care | 2017 |
| Cammeringham Consultants Ltd | Construction | 2015 |
| Camms Close Management Company Limited | Households | 2025 |
| Campbell Engineering Ltd | Professional & scientific | 2024 |
| Camper 2011 Holdings Limited | Professional & scientific | 2011 |
| Camper 2023 Holdings Limited | Financial services | 2023 |
| Camper UK Leisure Limited | Hospitality | 2017 |
| Camper UK Limited | Other services | 2004 |
| Campions S&B Limited | Professional & scientific | 2016 |
| Camspar Ltd | Health & social care | 2019 |
| Candid Estate Planning Ltd | Financial services | 2015 |
| Candyfloss Maintenance Services LLP | | 2013 |
| Canine Hoopers UK | Education | 2017 |
| Canner Holdings Ltd | Real estate | 2026 |
| Cantel Global Ltd | Information & communication | 2018 |
| Canwick House Care Home Limited | Health & social care | 2009 |
| Cape Quantity Surveying Limited | Professional & scientific | 2007 |
| Capella Accounting Ltd | Professional & scientific | 2021 |
| Capital Advisory Group (UK) Limited | Extraterritorial | 2012 |
| Capital Direct Management (UK) Limited | Financial services | 2016 |
| Capital Medical Consulting Ltd | Health & social care | 2011 |
| Capitalbase Limited | Other services | 1989 |