| C&L Concepts Limited | Information & communication | 2017 |
| C.T. Butler Ltd | Manufacturing | 2017 |
| California Sacramento Limited | Financial services | 2016 |
| Cambridge Children Ltd | Real estate | 1992 |
| Cambridge Gliding Club Limited | Arts & recreation | 1952 |
| Cambridge IT Management Limited | Professional & scientific | 1997 |
| Canada Support Services Limited | Professional & scientific | 2013 |
| Canape Ltd | Hospitality | 2025 |
| Candlestick Films Limited | Information & communication | 2016 |
| Carespace Services Ltd | Health & social care | 2026 |
| Carey Senter Associates Ltd | Education | 2012 |
| Carreraplanes Limited | Other services | 2008 |
| Carter James Estates Ltd | Real estate | 2025 |
| Carterspsl Limited | Information & communication | 2013 |
| Carty Services Ltd | Transport & logistics | 2015 |
| Cassiopeiauk Limited | Other services | 2023 |
| Catriona Hammond Interior Design Limited | Professional & scientific | 2022 |
| CC Electrical Solutions Ltd | Construction | 2017 |
| CCR Accident Repairs Limited | Wholesale & retail | 2020 |
| CDH Engineering Ltd | Professional & scientific | 2022 |
| Cell Metric Limited | Manufacturing | 2005 |
| Central Nexus Ltd | Information & communication | 2025 |
| Cfortress Ltd | Professional & scientific | 2024 |
| Chalice Investment Club Limited | Financial services | 2026 |
| Charlie Coffee Ltd | Hospitality | 2017 |
| Charnock House Limited | Real estate | 2015 |
| Charnocks Close House Owners Association Limited | Households | 1975 |
| Chasing Tails Ltd | Other services | 2026 |
| Chattoraj Limited | Wholesale & retail | 2021 |
| Chavil Limited | Administrative & support | 2012 |
| Chicken Days Ltd | Hospitality | 2023 |
| Chippie Brown Kitchen & Bedroom Installations Limited | Manufacturing | 2011 |
| Chocolatier DE France Limited | Manufacturing | 2009 |
| Church House Willingham Management Limited | Households | 2006 |
| Church of GOD International Ltd | Other services | 2020 |
| Cinq Amis Limited | Information & communication | 2018 |
| CJ Decs Ltd | Construction | 2025 |
| CJP Trading Ltd | Wholesale & retail | 2025 |
| Claridge Landscapes Limited | Administrative & support | 2012 |
| CLARITY4D Limited | Professional & scientific | 2008 |
| Cleaning Diva Services Ltd | Administrative & support | 2026 |
| CLEARIDGE1818 Limited | Information & communication | 2026 |
| Cloud 9 Adventure Limited | Administrative & support | 2013 |
| Clue HQ Bedford Limited | Arts & recreation | 2017 |
| CMS Trans Ltd | Transport & logistics | 2023 |
| Coach House Court (Gamlingay) Limited | Households | 2005 |
| Coach N Co Ltd | Professional & scientific | 2025 |
| Colfax Corporate Limited | Financial services | 2020 |
| Colfax Corporate Services Limited | Financial services | 2020 |
| Colfax ND One Limited | Financial services | 2021 |
| Colfax ND Two Limited | Financial services | 2021 |
| Colfax Share Trustees Limited | Financial services | 2021 |
| Colin Grove Ltd | Information & communication | 2022 |
| Colin Seaman Roofing Limited | Construction | 2003 |
| Comfort and Care Ltd | Wholesale & retail | 2026 |
| Compton Auto Services Limited | Wholesale & retail | 2024 |
| Conor Inskip Fitness Studios Ltd | Arts & recreation | 2025 |
| Contego Services Limited | Professional & scientific | 2007 |
| Contoura Publishing Ltd | Information & communication | 2025 |
| Cooper Labour Solutions Ltd | Construction | 2025 |
| Core Skills Development Limited | Education | 2020 |
| Cornelus Bucatea Limited | Transport & logistics | 2023 |
| Cornerstone & Counsel Ltd | Professional & scientific | 2026 |
| Corven Golf Limited | Wholesale & retail | 2026 |
| Cosmos Prince Limited | Information & communication | 2020 |
| Costi Andrei Ltd | Administrative & support | 2021 |
| County Life Publishing Ltd | Information & communication | 2008 |
| County Vale Scaffolding Ltd | Construction | 2026 |
| Coxall Associates Ltd | Other services | 2014 |
| Cozy Tours LLP | | 2009 |
| Cozy Travel Limited | Transport & logistics | 1994 |
| Cozy's Property Services Limited | Real estate | 2021 |
| Crescent Radio Limited | Wholesale & retail | 1965 |
| Cronin Estates Ltd | Real estate | 2006 |
| Crowtree Consultants Limited | Professional & scientific | 2013 |
| Cryssdriving Services Ltd | Transport & logistics | 2021 |
| CTC Trans Ltd | Transport & logistics | 2022 |
| CTQ-27 Ltd | Information & communication | 2026 |
| Curry House Sandy Ltd | Hospitality | 2026 |
| CUT and Splice Media Limited | Information & communication | 2011 |
| CUT the Mustard Films Limited | Information & communication | 2013 |
| Cybrist Limited | Manufacturing | 2021 |
| Cydonia Productions Ltd | Information & communication | 2024 |
| D C Norris & Company Ltd. | Manufacturing | 1973 |
| D J Hare Consultancy Limited | Administrative & support | 2011 |
| D&D Vapes Ltd | Wholesale & retail | 2020 |
| Daddy Bread Limited | Health & social care | 2014 |
| Dalenius Ltd | Information & communication | 2025 |
| Dalpo Group UK Limited | Financial services | 2026 |
| Dancing Barefoot Limited | Wholesale & retail | 2019 |
| DANIFELIX0992 Ltd | Health & social care | 2023 |
| Danny Sewell Limited | Financial services | 2019 |
| Darmah Properties Limited | Real estate | 2025 |
| Dartly Ltd | Wholesale & retail | 2026 |
| Davenport Cars Limited | Wholesale & retail | 2008 |
| Davey Joinery Ltd | Manufacturing | 2013 |
| Davyd Transport Limited | Transport & logistics | 2017 |
| Deacon GAS and Heating Ltd | Construction | 2023 |
| Dean Street Voices Limited | Professional & scientific | 2021 |
| Decal Station UK Ltd | Manufacturing | 2020 |