| Canvas Crusaders Ltd | Professional & scientific | 2025 |
| Capella Investments Limited | Financial services | 2024 |
| Capital Ductwork Ltd | Manufacturing | 2022 |
| Capricorn Software (International) Limited | Construction | 1986 |
| Caprilia Ltd | Information & communication | 2012 |
| Car and Trailer Driving School Limited | Education | 2016 |
| Car Home & Garden Limited | Wholesale & retail | 1978 |
| Car Investment Group Ltd | Wholesale & retail | 2024 |
| Carbelim UK Limited | Professional & scientific | 2023 |
| Carefall Care Ltd | Information & communication | 2019 |
| Carerise Healthcare Ltd | Health & social care | 2022 |
| Carvon Ltd | Real estate | 2011 |
| CAS Plumbing Ltd | Construction | 2023 |
| Cask Quest Limited | Extraterritorial | 2015 |
| Catty Catty Ltd | Wholesale & retail | 2012 |
| Cawston Management Ltd | Real estate | 2014 |
| Cawston Roofing Ltd | Construction | 2019 |
| Caxton Street North Management Limited | Real estate | 2019 |
| CCG Sales Ltd | Wholesale & retail | 2014 |
| Chalom Ltd | Professional & scientific | 2023 |
| Chamberlain & Hollick Ltd | Real estate | 2020 |
| Chamberlain Precision Limited | Manufacturing | 2001 |
| Chariots Ltd | Construction | 2009 |
| Charles Antony Group Ltd | Real estate | 2026 |
| Cheaper Energy Consultants Ltd | Information & communication | 2022 |
| Checkmate Lifting & Safety Ltd | Manufacturing | 2011 |
| Cheriton Motor Company Limited | Wholesale & retail | 2021 |
| Cherrytree Hydrotherapy Ltd | Professional & scientific | 2015 |
| Chesley Limited | Real estate | 1995 |
| Children and Families Childcare Limited | Health & social care | 2011 |
| Children and Families Children’S Centres Limited | Health & social care | 2014 |
| Children and Families Limited | Health & social care | 2002 |
| Chotto Desh Catering Ltd | Hospitality | 2019 |
| Chrome Management Ltd | Professional & scientific | 2018 |
| Circle Property Investments Ltd | Real estate | 2017 |
| CJB Thermal Services Ltd | Construction | 2025 |
| CJS Smart Repairs Ltd | Wholesale & retail | 2025 |
| Cladd Spec Ltd | Construction | 2016 |
| Clarks Groundworks and Landscaping Ltd | Construction | 2021 |
| Clean Breeze Ltd | Administrative & support | 2025 |
| Clifton Holiday Parks Ltd | Hospitality | 2005 |
| Clinico Doors Ltd | Construction | 2024 |
| Clique Consultancy Ltd | Information & communication | 2023 |
| Clobo's Limited | Other services | 2011 |
| CNC Electrical Solutions Limited | Construction | 2017 |
| Coffee PAD Ltd | Hospitality | 2022 |
| Coldflow Holdings Ltd | Real estate | 2024 |
| Coldflow Refrigeration Limited | Wholesale & retail | 2010 |
| Collaboration Network Holdings LLP | | 2024 |
| Comestar Ltd | Hospitality | 2018 |
| Complaints EQ Limited | Administrative & support | 2018 |
| Concrete Transport Solutions Limited | Transport & logistics | 2007 |
| Confidential Document Destruction Limited | Water & waste | 2017 |
| CONN3CTED Services Ltd | Administrative & support | 2023 |
| Connected Discovery Ltd | Professional & scientific | 2011 |
| Constance Creations Limited | Wholesale & retail | 2019 |
| Cooper Crouse-Hinds (UK) Ltd. | Manufacturing | 1999 |
| Cosgrave Leisure Parks UK Limited | Hospitality | 2016 |
| Cosgrove Land Holdings Ltd | Real estate | 2018 |
| Cosgrove Leisure (Wayside) Limited | Construction | 2014 |
| Cosgrove Leisure Holdings Ltd | Real estate | 2018 |
| Cosgrove Leisure Parks UK Ashcroft Coast (1) Limited | Real estate | 2018 |
| Cosgrove Leisure Parks UK Decking Ltd | Manufacturing | 2020 |
| Cosgrove Leisure Parks UK Limited | Hospitality | 2016 |
| Cosgrove Leisure Parks UK Seasalter Ltd | Hospitality | 1953 |
| Cosgrove Leisure Parks UK Shurland Dale (2) Limited | Real estate | 2018 |
| Cosgrove Leisure Thames Retreat Limited | Hospitality | 2017 |
| Cosgrove Resorts UK Limited | Financial services | 2023 |
| County Electrical Services (Kent) Ltd | Construction | 2007 |
| CPH Management Ltd | Professional & scientific | 2021 |
| Cplex Engineering UK Ltd | Construction | 2023 |
| Cresco Commercial Ltd | Administrative & support | 2023 |
| Cripps Farm Limited | Agriculture & fishing | 2024 |
| Croindene Court (Minster) Management Company Limited | Real estate | 2000 |
| Crosswell Screeding Limited | Construction | 2005 |
| Crown TOT Investment Limited | Real estate | 2023 |
| CRS Traffic Ltd | Construction | 2023 |
| Crystal Energy Management Limited | Other services | 2010 |
| CTC Flooring Prep Limited | Construction | 2025 |
| Ctech Technology Services Ltd | Other services | 2025 |
| Cuddles and Bubbles Ltd | Wholesale & retail | 2017 |
| Cussens Agricultural Enterprises Ltd | Agriculture & fishing | 2025 |
| CUT and Glow Ltd | Other services | 2018 |
| CWB Property & Maintenance Ltd | Real estate | 2025 |
| Cyprus Catering Ltd | Hospitality | 2023 |
| Cyprus Dinner Takeaway Ltd | Hospitality | 2019 |
| D & S Creations Events Ltd | Arts & recreation | 2022 |
| D Buckley Limited | Construction | 2007 |
| D&Bw Property Limited | Real estate | 2023 |
| D&D Takeaway Ltd | Hospitality | 2021 |
| D&D Training Limited | Education | 2024 |
| D&M Green Holding Ltd | Real estate | 2022 |
| D&M Property Company Ltd | Construction | 2011 |
| D.P.W. Investments Limited | Real estate | 2014 |
| Dakota’S Pawfection Ltd | Wholesale & retail | 2019 |
| Dalea Transport Services Ltd | Transport & logistics | 2024 |
| Damage Assist Ltd | Construction | 2020 |
| DAN & ELL Care Ltd | Health & social care | 2026 |
| Daniel Sims Photography Limited | Professional & scientific | 2013 |
| Danley Marshes Riding Centre Ltd | Agriculture & fishing | 2026 |