| Build-It Solutions Ltd | Wholesale & retail | 2023 |
| Bulgar 93 Ltd | Administrative & support | 2025 |
| BWH Legal Limited | Professional & scientific | 2016 |
| BWM Arms Limited | Arts & recreation | 2001 |
| BWP Commercial Property Ltd | Real estate | 2022 |
| BYTES4BITES Limited | Information & communication | 2024 |
| C Charles Flooring Limited | Construction | 2012 |
| Ca-Health Limited | Health & social care | 2022 |
| Cable Free Vision Limited | Information & communication | 2012 |
| Cafe Lalilano Ltd | Wholesale & retail | 2025 |
| Cafélias Ltd | Hospitality | 2022 |
| Calchar Logisitcs Ltd | Transport & logistics | 2025 |
| Cambridge Implants Limited | Manufacturing | 2020 |
| Caminito Foods Limited | Hospitality | 2022 |
| Cantina Holdings Ltd | Financial services | 2023 |
| Cantina Mariachi Ltd | Hospitality | 2016 |
| Cantina Property Ltd | Real estate | 2023 |
| Carereach 24/7 Healthcare Services Limited | Health & social care | 2024 |
| Carlinport Limited | Wholesale & retail | 1978 |
| Carney and Kirkman Developments Ltd | Real estate | 2025 |
| Cars Auto Spa Limited | Administrative & support | 2024 |
| Carswell Capital Ltd | Real estate | 2025 |
| Carter Home & Garden Improvements Ltd | Construction | 2021 |
| Cartifye Limited | Wholesale & retail | 2023 |
| Cashmere Continental Foods & Cosmetics Ltd | Wholesale & retail | 2024 |
| Caterfix Equipment Services Ltd | Manufacturing | 2017 |
| Catlin Exceptional Homes Ltd | Construction | 2024 |
| Catlin Ltd | Construction | 2013 |
| CBT Beard Ltd | Construction | 2019 |
| CC Prime Transport Limited | Wholesale & retail | 2026 |
| CCB Property Holding Ltd | Real estate | 2026 |
| Cctech Cloud Ltd | Information & communication | 2013 |
| CDB (CI) Ltd | Financial services | 2025 |
| CDB Autos Ltd | Wholesale & retail | 2018 |
| Cdbrh Ltd | Financial services | 2023 |
| Cdbrps Ltd | Financial services | 2023 |
| CDC Electrical Services Limited | Construction | 2018 |
| Cell Phone Repairs Didcot Limited | Other services | 2026 |
| CENTURY21 Sandcastle Ltd | Real estate | 2021 |
| CH Accounting and Tax Limited | Professional & scientific | 2026 |
| Chain of Ponds Limited | Information & communication | 2007 |
| Chapel Court 3 Ltd | Real estate | 2025 |
| Chapel Court 4 Ltd | Real estate | 2025 |
| Chapter House Management Services Limited | Households | 2006 |
| Charge Point Solutions Oxford Ltd | Construction | 2022 |
| Charles Stutley Ltd | Professional & scientific | 2013 |
| Charlie and Millie Co Ltd | Wholesale & retail | 2020 |
| Chartula Studio Ltd | Education | 2006 |
| Charvik Trading Ltd | Wholesale & retail | 2025 |
| Chaseai Ltd | Health & social care | 2023 |
| Chepstow Advisory Limited | Hospitality | 2016 |
| Chequers Garage Limited | Wholesale & retail | 2008 |
| Cherry Enterprises Limited | Health & social care | 2007 |
| Cherry Space Limited | Professional & scientific | 2016 |
| Cherry Tree Marketing Ltd | Professional & scientific | 2023 |
| Chestnut Legacy Limited | Real estate | 2026 |
| Chilled Piranha Ltd | Extraterritorial | 2010 |
| Chillexion Ltd | Information & communication | 2025 |
| Chillibongo Pets Limited | Professional & scientific | 2019 |
| Chinese Food Services Ltd | Hospitality | 2025 |
| Ching Yuet Ltd | Wholesale & retail | 2021 |
| Chinothai Ltd | Hospitality | 2022 |
| Chip Synergy Ltd | Information & communication | 2019 |
| Choi's Chinese Take Away Limited | Hospitality | 2015 |
| Chor Muang Ltd | Hospitality | 2018 |
| Chris Boulton Consulting Limited | Professional & scientific | 2017 |
| Chruz Consults Limited | Professional & scientific | 2017 |
| Church of GOD - United Kingdom | Other services | 1995 |
| CI Informatics Limited | Information & communication | 2009 |
| Cibus Solutions Ltd | Professional & scientific | 2023 |
| Circles South East | Other services | 2008 |
| Citrus Global London Ltd | Real estate | 2025 |
| City Road Apartments Ltd | Real estate | 2019 |
| Cjpm Consulting Ltd | Professional & scientific | 2026 |
| Clarence Commercial Ltd | Real estate | 2024 |
| Clarendons Care Ltd | Wholesale & retail | 2025 |
| Clarendons Pharmacy Ltd | Wholesale & retail | 2020 |
| Clarus Brickwork Limited | Construction | 2026 |
| Classic Dwellings Limited | Construction | 2024 |
| Clean Construct Ltd | Professional & scientific | 2023 |
| Cleanscape Waste and Hygiene Ltd | Water & waste | 2026 |
| Cleest Ltd | Transport & logistics | 2021 |
| Cleva Management Limited | Administrative & support | 2025 |
| Click Spark Ltd | Wholesale & retail | 2022 |
| Cljw Investments Ltd | Real estate | 2025 |
| Coalesce Works Limited | Information & communication | 2016 |
| Cobden Centre Management Company Limited | Professional & scientific | 2000 |
| Coco's Gardening Ltd | Administrative & support | 2020 |
| Codcee Ltd | Health & social care | 2022 |
| Coderon Tech AI Ltd | Education | 2025 |
| Cogent Method Limited | Information & communication | 2000 |
| Comeg Construction Limited | Construction | 2004 |
| Comlets Ltd | Real estate | 2013 |
| Connect Intellectual Property Limited | Professional & scientific | 2003 |
| Connected Apps Ltd | Information & communication | 2023 |
| Connell Investments Limited | Real estate | 1958 |
| Converge Property Limited | Real estate | 2025 |
| Copeland Select Limited | Professional & scientific | 2009 |
| Corcoran Flats Management Limited | Households | 2008 |
| Corelogic Ltd | Information & communication | 2024 |