| County Pest Control Services Limited | Administrative & support | 2002 |
| Countyoak Homes Limited | Construction | 2019 |
| Countyoak SB Limited | Financial services | 2019 |
| Courtney Green Block & Estate Management Ltd | Households | 2019 |
| Courtney Green Limited | Real estate | 2009 |
| Couzens&Hale Holdings Ltd | Wholesale & retail | 2025 |
| Cover Connect Limited | Financial services | 2025 |
| Cover Motion Limited | Financial services | 2025 |
| Cowfold Cottage Indian Food Limited | Hospitality | 2019 |
| Cowfold Rejuvenation Clinic Ltd | Health & social care | 2026 |
| COX & Co Consulting Ltd | Professional & scientific | 2017 |
| COX Green Ltd | Real estate | 1994 |
| COX Green Training Limited | Education | 2007 |
| Coyne Construction Limited | Construction | 1960 |
| Coyne Developments (Raynes Park) Limited | Real estate | 2015 |
| CPM Financial Planning Limited | Professional & scientific | 2012 |
| Cpmp Network Ltd | Construction | 2020 |
| CPT Global Ltd | Information & communication | 1998 |
| CR Hobbies Ltd | Manufacturing | 2024 |
| Cracking Baps Limited | Hospitality | 2022 |
| Cragg Hall Securities Ltd | Construction | 2014 |
| Craig Lowry Property Services Ltd | Professional & scientific | 2015 |
| Crane Management Services Limited | Transport & logistics | 2008 |
| Cranleigh Controls Limited | Manufacturing | 2009 |
| Cravecave Ltd | Hospitality | 2025 |
| Cravespot Ltd | Real estate | 1987 |
| Crawley Carpet Warehouse (Commercial) Ltd | Construction | 2021 |
| Crawley Carpet Warehouse (Domestic) Ltd | Wholesale & retail | 2021 |
| Crawley Down Butchers Limited | Wholesale & retail | 2016 |
| Crawley Family Lawyers Ltd | Professional & scientific | 2018 |
| Crawley Foot Health Clinic Limited | Health & social care | 2022 |
| Crawley MB Ltd | Hospitality | 2024 |
| Crazy Beanz Ltd | Arts & recreation | 2017 |
| CRE8ATE Ltd | Professional & scientific | 2012 |
| Crea Studio Limited | Professional & scientific | 2019 |
| Crealock Limited | Professional & scientific | 2014 |
| Create Recovery Limited | Health & social care | 2014 |
| Creative Cabinets Limited | Manufacturing | 2009 |
| Creative Code Labs Ltd. | Information & communication | 2017 |
| Creative Geology Limited | Wholesale & retail | 2014 |
| Creative Licence U.K. Limited | Arts & recreation | 2006 |
| Creative Metal Design Limited | Construction | 2017 |
| Creative Refurbs Limited | Construction | 2013 |
| Creative Spark Services Ltd | Construction | 2015 |
| Creative Technologies Ltd | Information & communication | 2009 |
| Creativespirit Design Limited | Professional & scientific | 2014 |
| Creatus Worldwide Ltd | Extraterritorial | 2014 |
| Creekwood Garden & Gift Limited | Wholesale & retail | 2023 |
| Creggan Properties Limited | Real estate | 1959 |
| Cresslands Property Limited | Real estate | 2005 |
| Crestawood Limited | Administrative & support | 2014 |
| Cribbs Speed Shop Ltd | Wholesale & retail | 2025 |
| Crickmay Limited | Real estate | 2001 |
| Cripandip Limited | Arts & recreation | 2025 |
| Crisfield Properties Limited | Construction | 1958 |
| Crisp Enterprises Limited | Construction | 2002 |
| Critical Canvas Ltd | Arts & recreation | 2025 |
| CRL (UK) Ltd | Professional & scientific | 2011 |
| CRL Developments (Berkshire) Ltd | Construction | 2014 |
| Crma Electrical Limited | Construction | 2021 |
| Croal Limited | Information & communication | 2006 |
| Crombie Management Consulting Ltd | Professional & scientific | 2015 |
| Cropday Ltd | Agriculture & fishing | 2022 |
| Crosdil Leisure Limited | Wholesale & retail | 2021 |
| Cross Education Support Services Ltd | Administrative & support | 2003 |
| Crown CS Limited | Professional & scientific | 2017 |
| Crown Fire Systems Ltd | Construction | 2023 |
| Crucible Studio Ltd | Financial services | 2025 |
| Crust King Ltd | Wholesale & retail | 2025 |
| CRX Services Limited | Professional & scientific | 2026 |
| CRY for the Moon Limited | Wholesale & retail | 2003 |
| Crystal Cars Airport Transfer Ltd | Transport & logistics | 2023 |
| Crystal Technology Limited | Information & communication | 1998 |
| Crystals Boutique Limited | Wholesale & retail | 2016 |
| CSG Decorating Limited | Construction | 2021 |
| CSG Haulage Ltd | Transport & logistics | 2023 |
| CST Cleaning Ltd | Administrative & support | 2024 |
| CTA Heating Services Ltd | Construction | 2021 |
| CTR Interstellar Limited | Transport & logistics | 2022 |
| Cubic Controls Limited | Information & communication | 2018 |
| Cubitt & West Estate Agents Limited | Extraterritorial | 1992 |
| Cuckoo Cherry Tree LLP | | 2011 |
| Cuckoo Horsham Limited | Wholesale & retail | 2022 |
| Curators Coffee Limited | Hospitality | 2017 |
| Curo Consulting Limited | Professional & scientific | 2002 |
| Cursons Business Consulting Limited | Information & communication | 2025 |
| Curzon Fabrication Ltd | Manufacturing | 2022 |
| Cusack Financial Management Limited | Financial services | 2004 |
| Cuss Property Holdings Limited | Real estate | 2025 |
| Custom Coachworks (Burgess Hill) Ltd | Wholesale & retail | 2018 |
| Custom Coachworks (Uckfield) Ltd | Wholesale & retail | 2022 |
| Custom Quest Limited | Extraterritorial | 1998 |
| CUT to Air Productions Ltd | Information & communication | 2021 |
| Cutebitz Limited | Wholesale & retail | 2008 |
| Cuttlefish Group Limited | Real estate | 2016 |
| CVR Equestrian Limited | Agriculture & fishing | 2020 |
| CVS Guildford Limited | Wholesale & retail | 2018 |
| CWG Commercial Limited | Construction | 2026 |
| CWG Electrical Limited | Construction | 2026 |
| CWG New Build Limited | Construction | 2026 |