| Countfast Ltd | Wholesale & retail | 2010 |
| Country & Colonial Limited | Wholesale & retail | 1995 |
| Country Club Media Group Limited | Information & communication | 2025 |
| Countryside Home Improvements Limited | Construction | 2004 |
| County Care Services Ltd | Health & social care | 2021 |
| County Chambers Limited | Professional & scientific | 2001 |
| Courage Within Ltd | Administrative & support | 2022 |
| Courier Expres Ltd | Transport & logistics | 2020 |
| Courlan Limited | Wholesale & retail | 2024 |
| Courtney-Morgan Limited | Arts & recreation | 2016 |
| Covenant Connections With Auntie CEE Ltd | Other services | 2026 |
| Covin Limited | Real estate | 2014 |
| COW Corner Cricket Clothing Limited | Wholesale & retail | 2025 |
| Cowasset Limited | Real estate | 2025 |
| Cowboy Toad Games Ltd | Information & communication | 2024 |
| Cowell Healthcare Consultancy Ltd | Professional & scientific | 2025 |
| Cowise Ltd | Information & communication | 2024 |
| Coxbarratt Ltd | Real estate | 2026 |
| Coxy Recruits Ltd | Administrative & support | 2021 |
| Cozy Cove Ltd | Wholesale & retail | 2023 |
| CP Norfolk Ltd | Administrative & support | 2025 |
| CP Property Collective Ltd | Real estate | 2025 |
| CPC Agency Ltd | Health & social care | 2020 |
| CPK Group Limited | Wholesale & retail | 2023 |
| CPK Ventures Ltd | Wholesale & retail | 2025 |
| CPK Venturez Ltd | Wholesale & retail | 2025 |
| Cpsg-Uk Ltd | Administrative & support | 2021 |
| CQB Publications (UK) Limited | Wholesale & retail | 2004 |
| Cracknell Professional Services Ltd | Manufacturing | 2018 |
| Cradlefin Consultants Limited | Professional & scientific | 2018 |
| Cradlefin Group Limited | Transport & logistics | 2021 |
| Craftcore Studio Ltd | Professional & scientific | 2025 |
| Craftd Art Ltd | Wholesale & retail | 2026 |
| Craftful Ltd | Wholesale & retail | 2023 |
| Craftstack Ltd | Information & communication | 2026 |
| Craftxp Ltd | Wholesale & retail | 2025 |
| Crafty Case Kids Ltd | Wholesale & retail | 2023 |
| Crafty Tyme Ltd | Wholesale & retail | 2021 |
| Crake Family Homes Limited | Real estate | 2019 |
| Crane & Harbor Ltd | Wholesale & retail | 2025 |
| Cranes View Limited | Households | 2021 |
| Cranmer Property Management Ltd | Real estate | 2025 |
| Crashcube Ltd | Manufacturing | 2026 |
| Crazy GAL Limited | Wholesale & retail | 2023 |
| CRC Transformation Limited | Professional & scientific | 2018 |
| CRE8 Design Build Ltd | Construction | 2026 |
| CRE8ED CIC | Education | 2024 |
| Creacure Ltd | Wholesale & retail | 2025 |
| Creapod Ltd | Professional & scientific | 2017 |
| Creatdsupport Limited | Administrative & support | 2024 |
| Create Better Places Ltd | Real estate | 2021 |
| Create Space London | Arts & recreation | 2014 |
| Createcipline Studio Limited | Information & communication | 2026 |
| Createdstones Limited | Wholesale & retail | 2019 |
| Createntra Learning Limited | Information & communication | 2026 |
| Creatia Ltd | Manufacturing | 2025 |
| Creative Arts Ministry | Arts & recreation | 2004 |
| Creative Clues Ltd | Professional & scientific | 2023 |
| Creative Media Studio Ltd | Wholesale & retail | 2023 |
| Creative Property Investment Services Ltd | Real estate | 2023 |
| Creative Space and Investment Ltd | Hospitality | 2024 |
| Creatorbooks Ltd | Professional & scientific | 2026 |
| Creatorlevelup Ltd | Education | 2023 |
| Crej Ltd | Administrative & support | 2021 |
| Cremation Services Limited | Other services | 2023 |
| Creo DE Vere Limited | Construction | 2016 |
| Crescitaflorenst Ltd | Wholesale & retail | 2025 |
| Cresmedow Road Management Co. Limited | Households | 2003 |
| Crest & Crown Properties Ltd | Real estate | 2025 |
| Crestpoint IT Ltd | Information & communication | 2025 |
| Crewel Cuts Ltd | Extraterritorial | 2020 |
| Crewra Group Ltd | Information & communication | 2026 |
| CRG Windows Ltd | Administrative & support | 2023 |
| Cricket View (Mildenhall) Limited | Real estate | 2015 |
| Crisp Accountancy Ltd | Professional & scientific | 2016 |
| Crisp Contractor Ltd | Professional & scientific | 2013 |
| Crisp Group Ltd | Financial services | 2016 |
| Cristal Clean Window Cleaning Ltd | Administrative & support | 2024 |
| Cristi & Sons Ltd | Transport & logistics | 2024 |
| Criterion Cost Management Ltd | Construction | 2019 |
| Critical Building Services Limited | Other services | 2018 |
| Critical Computer Company Limited | Information & communication | 1995 |
| Critical Veterinary Ltd | Professional & scientific | 2026 |
| CRJ Accountancy Limited | Professional & scientific | 2003 |
| Crosby Kitchen Manufacturers UK Ltd | Manufacturing | 2017 |
| Cross Trades and Logistics Limited | Transport & logistics | 2009 |
| Crosscountry Medics Limited | Health & social care | 2025 |
| Crossip Ltd | Manufacturing | 2020 |
| Crossman Home Improvement Services Ltd | Construction | 2023 |
| Crossmark Limited | Wholesale & retail | 2020 |
| Crossover-Telecom Ltd | Information & communication | 2019 |
| Crossways Consultancy Ltd | Professional & scientific | 2022 |
| Crowdvc Ltd | Information & communication | 2025 |
| Crown & Reach Ltd | Professional & scientific | 2023 |
| Crown Africa Entertainment Ltd | Hospitality | 2026 |
| Crown Africa Trading Ltd | Wholesale & retail | 2026 |
| Crown Auto Solutions Ltd | Wholesale & retail | 2026 |
| Crown Street Management Company Limited | Households | 2017 |
| Crown Supported Accommodation Limited | Health & social care | 2025 |
| Crown Supported Living Spaces Ltd | Health & social care | 2019 |