| CB Plastering (South) Limited | Construction | 2008 |
| CB Structures Ltd | Professional & scientific | 2017 |
| CBD Expert Ltd | Wholesale & retail | 2021 |
| CCH Medical Limited | Health & social care | 2025 |
| Ccpc Limited | Professional & scientific | 2009 |
| Ccvc Limited | Health & social care | 2020 |
| CCW Tools Ltd | Wholesale & retail | 2000 |
| CDS Residential Ltd | Administrative & support | 2023 |
| Cebio Health Limited | Health & social care | 2025 |
| Cedar Group Interiors Limited | Construction | 2026 |
| Cedar London Limited | Administrative & support | 2005 |
| Cedar Packaging Drinks Limited | Manufacturing | 2019 |
| Cedar Packaging Limited | Manufacturing | 2012 |
| Cedar Press (Southern) Limited | Manufacturing | 1974 |
| Cedar Press Holdings Limited | Professional & scientific | 1993 |
| Celtic Equine Veterinary Practice Limited | Professional & scientific | 2015 |
| Cenes Ltd | Hospitality | 2014 |
| Ceramorph Ltd | Professional & scientific | 2026 |
| Cerebri I.T Ltd | Information & communication | 2018 |
| Cervidae Investments Limited | Real estate | 2019 |
| CF Anaesthesia Limited | Health & social care | 2014 |
| Cfacts Ltd | Professional & scientific | 2023 |
| Chadmore Sterling Limited | Health & social care | 2026 |
| Challenge - TM | Health & social care | 2021 |
| Chambers Cafe and Bistro Limited | Hospitality | 2021 |
| Chances Gives Choices Limited | Administrative & support | 2014 |
| Chandlers Transport Ltd | Transport & logistics | 2020 |
| Change of a Dress Limited | Wholesale & retail | 2012 |
| Changing Altitudes Ltd | Other services | 2010 |
| Chapmans Engineering Services Limited | Manufacturing | 2009 |
| Charlbury Developments Limited | Construction | 2016 |
| Charlie Baker Limited | Health & social care | 2020 |
| Chatterbox Community Pre-School Limited | Education | 2012 |
| Checkapayer Limited | Professional & scientific | 2022 |
| Checkgoal Limited | Arts & recreation | 1998 |
| Chelsea Cardiac Limited | Health & social care | 2014 |
| Chelseatown Limited | Construction | 2003 |
| Cheltenham Spine Clinic Limited | Health & social care | 2018 |
| Chemring Countermeasures Limited | Manufacturing | 1926 |
| Chemring Group PLC | Professional & scientific | 1905 |
| Chemring Group Staff Pension Scheme Trustee Limited | Financial services | 2024 |
| Chemring Holdings Limited | Professional & scientific | 1992 |
| Chemring North America Unlimited | Extraterritorial | 2008 |
| Chemring Prime Contracts Limited | Extraterritorial | 1994 |
| Chemring Technology Solutions Limited | Public administration | 1980 |
| Chesney Orthopaedic Services Limited | Health & social care | 2010 |
| Chichester HIP and Knee Limited | Health & social care | 2019 |
| Chillana Property Management Limited | Real estate | 2019 |
| Chilli Pepper Catering Limited | Manufacturing | 2018 |
| Chilworth Members Golf Company Limited | Other services | 2012 |
| Chinwhey Limited | Professional & scientific | 1976 |
| Chipstir Limited | Construction | 2009 |
| Chloros Environmental Ltd | Water & waste | 2008 |
| Chris Frost Consulting Ltd | Information & communication | 2020 |
| Chris Giles Limited | Information & communication | 2011 |
| Chris Hills Financial Consultancy Ltd | Financial services | 2004 |
| Chris Street Ltd | Hospitality | 2020 |
| Chris Wheatcroft Limited | Administrative & support | 2018 |
| Christopher & Harris Limited | Administrative & support | 2023 |
| Church Lane (Romsey) Management Limited | Households | 2022 |
| Churchell Entertainments Limited | Professional & scientific | 2014 |
| CI Promotions Limited | Wholesale & retail | 2003 |
| Ciggyjuice Group Ltd | Financial services | 2018 |
| CIH Marine Ltd | Administrative & support | 2025 |
| Cinergi Ltd | Other services | 2020 |
| CIR Mhor Medical Services Ltd | Health & social care | 2025 |
| Cjtr Medical Services Ltd | Health & social care | 2019 |
| CK Hewitt Ltd | Construction | 2011 |
| Clara Futura Limited | Other services | 2013 |
| Class Executive Cars Limited | Transport & logistics | 2023 |
| Classic 4X4 Hire Ltd | Administrative & support | 2019 |
| Classic 4X4 Ltd | Administrative & support | 2019 |
| Claudia Ashleigh (Bishops Waltham) Limited | Health & social care | 2010 |
| Claudia Ashleigh (Romsey) Limited | Health & social care | 2005 |
| Claudia Ashleigh Limited | Health & social care | 2002 |
| Clawddcam Solar Park Ltd | Energy | 2017 |
| Claybank Transport Services Ltd | Transport & logistics | 2017 |
| Clayton Medical Partnership LLP | | 2016 |
| Clean Contractors Ltd | Other services | 2010 |
| Cleanfix Limited | Other services | 2000 |
| Cleanroom Projects Group Limited | Extraterritorial | 2025 |
| Clear Perspective Media Design Ltd | Information & communication | 2020 |
| Clearsky Landholdings Ltd | Real estate | 2012 |
| Clearsky Properties Limited | Real estate | 1994 |
| Clearview Aerials Ltd | Administrative & support | 2003 |
| Clearwater Angling Solutions Ltd | Wholesale & retail | 2014 |
| Climbers Way Tree Care Limited | Administrative & support | 2014 |
| CLK Detailing and Valeting Ltd | Wholesale & retail | 2019 |
| CLS Developments Limited | Real estate | 1988 |
| CLS Investments and Developments Limited | Financial services | 2025 |
| CLT Medical Limited | Health & social care | 2017 |
| CMT Print Limited | Professional & scientific | 2019 |
| CMT Print London Limited | Professional & scientific | 2019 |
| Coast Property Solutions Ltd | Extraterritorial | 2016 |
| Coast Solutions Ltd | Extraterritorial | 2016 |
| Coastal Carpentry Installations Ltd | Manufacturing | 2025 |
| Coastal Home Improvements Ltd | Construction | 2026 |
| Coastal Maintenance Services Limited | Professional & scientific | 2005 |
| Coastal Orthopaedics Limited | Health & social care | 2012 |
| Cobra Hydro UK Limited | Manufacturing | 2005 |