| Cordelia's Health Care Limited | Health & social care | 2026 |
| Cordial Health Hub Private Ltd | Transport & logistics | 2022 |
| Cordtape Energy Management Systems Limited | Manufacturing | 2008 |
| Cordtape Environmental Services Limited | Construction | 1983 |
| Core Brickwork Limited | Construction | 2023 |
| Core Collections Limited | Professional & scientific | 2022 |
| Core Community Education Limited | Education | 2022 |
| Core CUT (Nationwide) Ltd | Other services | 2019 |
| Core Fitness Solutions Limited | Arts & recreation | 2015 |
| Core HR Consultancy Ltd | Administrative & support | 2023 |
| Core Industry Ltd | Construction | 2024 |
| Core Interior Solutions Limited | Construction | 2009 |
| Core Plus Castlebrooke Asset Management Limited | Real estate | 2016 |
| Core Safety and Training Solutions Ltd | Professional & scientific | 2011 |
| Core Scaffolding Limited | Construction | 2024 |
| Core Software Solutions Limited | Information & communication | 2023 |
| Core Solutions Europe Limited | Wholesale & retail | 2014 |
| Core Thoughts Limited | Professional & scientific | 2025 |
| Corebon Commercial Limited | Construction | 2025 |
| Corebrand Limited | Other services | 2002 |
| Corelco Ltd | Construction | 2017 |
| Coremep Solutions Ltd | Professional & scientific | 2025 |
| Corepixel Studio Ltd | Wholesale & retail | 2025 |
| Corepoint NDT Limited | Professional & scientific | 2026 |
| Corepulse Ltd | Information & communication | 2025 |
| Coreskill Learning Centre Ltd | Information & communication | 2025 |
| Coretrol Limited | Extraterritorial | 2010 |
| Corker Aggregates Ltd | Wholesale & retail | 2026 |
| Corker Properties Ltd | Construction | 2010 |
| Cornah Ltd | Construction | 2023 |
| Corner Clothing Shop Ltd | Wholesale & retail | 2024 |
| Corner Kabin Ltd | Wholesale & retail | 2026 |
| Corner PR Limited | Professional & scientific | 2003 |
| Cornershop (Sheffield) Limited | Wholesale & retail | 2007 |
| Cornerstone Build Limited | Construction | 2026 |
| Cornerstone Business Ltd | Hospitality | 2024 |
| Cornerstone Construction South Yorks Ltd | Construction | 2024 |
| Cornerstone Content Studios Ltd | Manufacturing | 2022 |
| Cornerstone Day Nurseries Ltd | Health & social care | 2002 |
| Cornerstone Developers Ltd | Construction | 2019 |
| Cornerstone Lettings Limited | Real estate | 2026 |
| Cornerstone Masonry & Construction Ltd | Construction | 2026 |
| Cornerstone Nurseries Ltd | Health & social care | 2017 |
| Cornerstone Post Ltd | Wholesale & retail | 2019 |
| Cornerstone Supplies Limited | Wholesale & retail | 1984 |
| Cornerstone Ventures Group Ltd | Hospitality | 2025 |
| Cornerstones Education Limited | Education | 2010 |
| Corniche Construction Ltd | Construction | 1985 |
| Cornish Beef Limited | Professional & scientific | 1993 |
| Cornish Place Freehold Ltd | Households | 2019 |
| Cornish Works Limited | Construction | 2019 |
| Cornwall and Isles of Scilly Investments Limited | Financial services | 2017 |
| Cornwall Signalling Services Limited | Professional & scientific | 2026 |
| Cornwall Works Management Limited | Households | 2005 |
| Cornweald Limited | Agriculture & fishing | 1996 |
| Coronation Court Health Care Limited | Health & social care | 2023 |
| Corporate Amalgamations Ltd | Professional & scientific | 2020 |
| Corporate and Personal Investigations Limited | | 1992 |
| Corporate Consultancy Link Limited | Professional & scientific | 2008 |
| Corporate Culture Coach Limited | Professional & scientific | 2025 |
| Corporate Vending Systems Limited | Transport & logistics | 2004 |
| Corporation Payroll Limited | Administrative & support | 2020 |
| Corps Commerce Ltd | Professional & scientific | 2015 |
| Corr Refractory & Building Limited | Construction | 2016 |
| Corralls Coal Limited | Extraterritorial | 1998 |
| Correct Choice Windows & Doors Ltd | Manufacturing | 2018 |
| Correct Epos Limited | Administrative & support | 2025 |
| Corso Italia Official Ltd | Hospitality | 2019 |
| Corte DE Diamante Ltd | Wholesale & retail | 2019 |
| Cortonwood (Management) Two Company Limited | Real estate | 2003 |
| Cortonwood Limited | Construction | 1986 |
| Cortworth Millhouse Ltd | Construction | 2013 |
| Cortworth Services Limited | Construction | 1974 |
| Corupa Ltd | Construction | 2024 |
| Corylana Limited | Arts & recreation | 2018 |
| Coryshine Limited | Other services | 2016 |
| Cosmarida Limited | Manufacturing | 2010 |
| Cosmedica by DJL Limited | Other services | 2019 |
| Cosmepod Ltd | Health & social care | 2026 |
| Cosmetic Auto Repairs Ltd | Wholesale & retail | 2012 |
| Cosmetic Beach Ltd | Other services | 2018 |
| Cosmetic Clinic Skincare Ltd | Wholesale & retail | 2021 |
| Cosmetic Junkie Ltd | Other services | 2011 |
| Cosmetic Repair Solutions (Derby) Ltd | Wholesale & retail | 2023 |
| Cosmetic Repair Solutions (Newcastle Upon Tyne) Ltd | Wholesale & retail | 2025 |
| Cosmetic Repair Solutions (Rotherham) Ltd | Wholesale & retail | 2017 |
| Cosmetica Clinic Limited | Health & social care | 2014 |
| Cosmetica Global Logistics Ltd | Wholesale & retail | 2021 |
| Cosmic Boop Ltd | Wholesale & retail | 2019 |
| Cosmic Collektiv Ltd | Arts & recreation | 2025 |
| Cosmicmilk Ltd | Financial services | 2022 |
| Cosmina Ltd | Other services | 2019 |
| Cosmo Build Ltd | Construction | 2018 |
| Cosmopolitan Holdings (Yorkshire) Limited | Financial services | 1992 |
| Cost-N-Consult Limited | Professional & scientific | 2012 |
| Costi Couriers Limited | Transport & logistics | 2024 |
| Costr Ltd | Professional & scientific | 2024 |
| Costs Solutions Limited | Professional & scientific | 2011 |
| Cosy Castle Ltd | Construction | 2024 |
| Cosy Club Retreats Ltd | Real estate | 2026 |