| Cosgrove Guest Services Ltd | Wholesale & retail | 2021 |
| Cosgrove Marina BR Limited | Administrative & support | 2015 |
| Cosgrove Marina Limited | Transport & logistics | 2025 |
| Cosly Ltd | Real estate | 2024 |
| Cosma Marius Ltd | Transport & logistics | 2018 |
| Cosmaconstruction Limited | Wholesale & retail | 2022 |
| Cosmak UK Ltd | Wholesale & retail | 2018 |
| Cosman Assist Limited | Administrative & support | 2017 |
| Cosmetic Product Luzern Limited | Wholesale & retail | 2024 |
| Cosmetics & Products Luzern Limited | Wholesale & retail | 2024 |
| Cosmeticsaesthetic Medical Limited | Wholesale & retail | 2024 |
| Cosmian Risk Management Ltd | Administrative & support | 2025 |
| Cosmic Code Ltd | Information & communication | 2024 |
| Cosmic Superstars Ltd | Other services | 2023 |
| Cosmin Eduard Ltd | Construction | 2014 |
| Cosmo Group Ltd | Administrative & support | 2025 |
| Cosmo Link AI Ltd | Information & communication | 2023 |
| Costa Trans Ltd | Transport & logistics | 2013 |
| Costardiv Ltd | Wholesale & retail | 2025 |
| Costel Servicess Limited | Construction | 2017 |
| Costtransport Ltd | Transport & logistics | 2019 |
| Costy Grecu Ltd | Construction | 2025 |
| Cosy Home Lettings Limited | Real estate | 2018 |
| Cosy Nest Living UK Limited | Wholesale & retail | 2025 |
| Cotech International Limited | Wholesale & retail | 2001 |
| Cotefield Interiors Ltd | Construction | 2005 |
| Cotels Connex Ltd | Real estate | 2023 |
| Cotels Ltd | Real estate | 2006 |
| Cotels Management Limited | Real estate | 2009 |
| Cotswold Aircraft Support Limited | Transport & logistics | 2010 |
| Cotswold View (Dursley) Management Limited | Households | 2001 |
| Cottee Property Ltd | Real estate | 2022 |
| Cottesford Pavilions Estate Residents' Association Limited | Households | 1982 |
| Cotton Comfort Ltd | Wholesale & retail | 2011 |
| Cotton Roots Ltd | Manufacturing | 2022 |
| Cottonblend Studio Limited | Wholesale & retail | 2024 |
| Cottonbloom Ltd | Wholesale & retail | 2025 |
| Cottrell Roofing Ltd | Construction | 2025 |
| Couchbase Limited | Information & communication | 2012 |
| Counsel Lane Ltd | Wholesale & retail | 2022 |
| Counselling Workshops & Training LLP | | 2013 |
| Countless Limited | Wholesale & retail | 2018 |
| Country and Coastal Parks 1 Holdco Limited | Arts & recreation | 2024 |
| Country and Coastal Parks 1 Limited | Arts & recreation | 2024 |
| Country and Coastal Parks 2 Holdco Limited | Arts & recreation | 2024 |
| Country and Coastal Parks 2 Limited | Arts & recreation | 2024 |
| Country and Coastal Parks 3 Holdco Limited | Arts & recreation | 2024 |
| Country and Coastal Parks 3 Limited | Arts & recreation | 2024 |
| Country and Coastal Parks 4 Holdco Ltd | Arts & recreation | 2025 |
| Country Developments Services Limited | Other services | 2020 |
| Country Hardwood Conservatories Limited | Manufacturing | 2007 |
| Country Hardwood Developments Limited | Other services | 2008 |
| Country Hardwood Orangeries & Conservatories Ltd | Extraterritorial | 2021 |
| Country Punk Limited | Public administration | 2020 |
| Country Taverns Limited | Hospitality | 1996 |
| Countrywide Insulation Ltd | Construction | 2025 |
| Countrywide Money Limited | Financial services | 2012 |
| Countrywide Principal Services Limited | Financial services | 1983 |
| Countrywide Promotions Limited | Administrative & support | 1999 |
| County Consultancy Services Limited | Information & communication | 2004 |
| Coupla Candys Ltd | Wholesale & retail | 2021 |
| Courier Savings Limited | Administrative & support | 2005 |
| Courrierai Ltd | Other services | 2024 |
| Courserv Ltd | Transport & logistics | 2019 |
| Courses for Professional Administrators Limited | Education | 1984 |
| Court House Care Properties Limited | Financial services | 2018 |
| Court House Care Services (Devon) Ltd | Health & social care | 2014 |
| Court Lane Landscapes Limited | Administrative & support | 2003 |
| Courtcare Flexi Limited | Health & social care | 2010 |
| Courtlands Management Company Limited | Households | 1982 |
| Courtyard Business Solutions Limited | Information & communication | 2023 |
| Courtyard Diner Limited | Hospitality | 2006 |
| Cove & SON Ltd | Construction | 2012 |
| Covenant Homes Services Ltd | Real estate | 2025 |
| Coverguard Security Limited | Administrative & support | 2021 |
| Coverguard Services Ltd | Administrative & support | 2008 |
| Coversite Security Services Ltd | Administrative & support | 2013 |
| Cowell Technologies Limited | Professional & scientific | 2021 |
| Cowrie Bros Ltd | Professional & scientific | 2023 |
| COX Family Investment Company Limited | Financial services | 2019 |
| Cox’S Telecommunications Ltd | Information & communication | 2023 |
| Coyne Accountancy Limited | Professional & scientific | 2020 |
| Cozonia Ltd | Wholesale & retail | 2022 |
| Cozy Property Group Ltd | Real estate | 2024 |
| Cozyshopping Limited | Wholesale & retail | 2026 |
| CP Grounds Maintenance Ltd | Administrative & support | 2017 |
| CP Virgo Limited | Construction | 2020 |
| CPA Bangladesh Limited | Education | 2025 |
| Cpburke Ltd | Professional & scientific | 2026 |
| CPI Holyoak Ltd | Financial services | 2019 |
| CPJ General Consulting and Procurement Services Limited | Administrative & support | 2020 |
| Cpml 2023 Limited | Real estate | 1996 |
| CPS Dt&L Limited | Transport & logistics | 2016 |
| Cpsm-Digital Ltd | Administrative & support | 2024 |
| CR Bloom Immigration Ltd | Professional & scientific | 2025 |
| CR Consulting & Property Limited | Professional & scientific | 2015 |
| CR Events Limited | Hospitality | 2025 |
| CR Residencies Ltd | Real estate | 2026 |
| Cra-Iq Ltd | Professional & scientific | 2025 |
| Crabtree Estates Limited | Real estate | 2009 |