| Crane Construction & Landscaping Ltd | Construction | 2024 |
| Cranog Investments Limited | Financial services | 2024 |
| Crav'D Ltd | Manufacturing | 2026 |
| Crazenation Ltd | Arts & recreation | 2013 |
| Crazy Fried Chicken Ltd | Hospitality | 2017 |
| Crazy Goat Leverstock Limited | Wholesale & retail | 2020 |
| CRC Contracts (Flooring) Limited | Wholesale & retail | 1998 |
| Creative Build Evolution Ltd | Construction | 2018 |
| Creative Business Systems Limited | Information & communication | 1981 |
| Creative Cleaning Services Ltd | Administrative & support | 2017 |
| Creative Contractors London Ltd | Construction | 2021 |
| Creative House Design Limited | Administrative & support | 1996 |
| Creative Scalps Limited | Health & social care | 2018 |
| Creativepool Ltd | Information & communication | 2006 |
| Creek Investments Ltd | Real estate | 2012 |
| CREO360 Ltd | Professional & scientific | 2017 |
| Crep Hero Ltd | Administrative & support | 2023 |
| Crepsbycooper Ltd | Wholesale & retail | 2021 |
| Crescent Gardens (Clitheroe) Management Company Limited | Households | 2023 |
| Crescenzo Limited | Professional & scientific | 2012 |
| Cresira Capital Limited | Information & communication | 2025 |
| Cress Lake Weddings Ltd | Administrative & support | 2023 |
| Crest Broadcast Solutions Limited | Professional & scientific | 2007 |
| Crest Design Ltd | Manufacturing | 2023 |
| Crest Power Solutions Ltd | Administrative & support | 2012 |
| Cretanu Services Ltd | Construction | 2026 |
| Crew Marketing Limited | Professional & scientific | 2018 |
| CRH Developments Limited | Construction | 2017 |
| Cribbes Engineering Ltd | Information & communication | 2022 |
| Cribbs Triangle (Almondsbury) Resident Management Company Limited | Households | 2023 |
| Crichlow Medicals Ltd | Health & social care | 2010 |
| Crimson Kite Construction Ltd | Construction | 2022 |
| Cringe Technologies Limited | Information & communication | 2012 |
| Crisps Looks Limited | Manufacturing | 2024 |
| Criss Trasport Ltd | Transport & logistics | 2015 |
| Cristalin Limited | Real estate | 2024 |
| Cristian Chauffering Ltd | Transport & logistics | 2024 |
| Criterion Flooring Ltd | Manufacturing | 2022 |
| CRJ Global LLP | | 2019 |
| CRJ International (Sign) Limited | Construction | 2017 |
| CRK Windows Limited | Manufacturing | 1985 |
| CRM Taverns (Holding 2) Ltd | Financial services | 2022 |
| CRM Taverns Ltd | Hospitality | 2022 |
| Croft END (Orwell) Management Company Limited | Households | 2019 |
| Cromwell Hart Ltd | Financial services | 2025 |
| Cross Consultancy Ltd | Professional & scientific | 2025 |
| Cross CUT Carpentry and Construction Ltd | Construction | 2015 |
| Cross Farm Mews Owners Limited | Households | 2005 |
| Cross Watch Co. Ltd | Manufacturing | 2026 |
| Crossing Point Developments Ltd | Real estate | 2026 |
| Crossworld Properties Ltd | Real estate | 2023 |
| Crow Services Ltd | Wholesale & retail | 2022 |
| Crown Link Properties Ltd | Real estate | 2025 |
| Crown Rest Beds Limited | Manufacturing | 2026 |
| Crownaura Ltd | Professional & scientific | 2025 |
| Croxley Electrical Limited | Construction | 2012 |
| CRS Drylining Ltd | Construction | 2025 |
| Crumbs by Collette Ltd | Manufacturing | 2020 |
| Crumlin Farmstead Ltd | Real estate | 2025 |
| CRW Building Services Limited | Construction | 2018 |
| Cryptogo Ltd | Information & communication | 2023 |
| CS UK Solutions Limited | Professional & scientific | 2013 |
| Cs&N Limited | Information & communication | 2017 |
| Csaa Engineering Ltd | Information & communication | 2015 |
| CSB Contracts Ltd | Construction | 2021 |
| CSCH12 Ltd | Real estate | 2015 |
| Csck Construction Ltd | Construction | 2016 |
| Csck Plumbing & Heating Ltd | Construction | 2019 |
| Csjn (Day Nurseries) Limited | Health & social care | 2024 |
| CST Surveys Limited | Professional & scientific | 2015 |
| CT Lamb Electrical Ltd | Construction | 2022 |
| CT Search Limited | Administrative & support | 2025 |
| CT Smoothlines Limited | Health & social care | 2016 |
| CTE Trading Ltd | Wholesale & retail | 2021 |
| CTI Projects Limited | Information & communication | 2018 |
| CTS Capital Ltd | Financial services | 2025 |
| Cube Assist Consultancy Ltd | Information & communication | 2023 |
| Cubic Fulfilment Limited | Transport & logistics | 2026 |
| Cueue Ltd | Professional & scientific | 2021 |
| Cuffley 1960 Limited | Extraterritorial | 2014 |
| Cullum Publishing Limited | Information & communication | 2002 |
| Culmen Analytics Limited | Information & communication | 2014 |
| Culmen Group Limited | Information & communication | 2014 |
| Culmen Solutions Limited | Information & communication | 2014 |
| Culture Centred Homecare Ltd | Health & social care | 2026 |
| Culture Together Ltd | Professional & scientific | 2026 |
| Cura Talent Ltd | Administrative & support | 2024 |
| Cureyoursearch Ltd | Administrative & support | 2021 |
| Curious Luxury Limited | Wholesale & retail | 2017 |
| Curious Vision Limited | Administrative & support | 2016 |
| Curtis & Co Ltd | Professional & scientific | 2005 |
| Curtis Comms Ltd | Information & communication | 2002 |
| Customised Safety Solutions Ltd | Professional & scientific | 2014 |
| CUT a Dash Tailoring (MTM) Ltd | Manufacturing | 2022 |
| CUT a Dash Tailoring Ltd | Wholesale & retail | 2018 |
| CW & JC Properties Limited | Real estate | 2016 |
| CW Accountancy Solutions Ltd | Professional & scientific | 2025 |
| CWH Consultants (Herts) Limited | Professional & scientific | 2024 |
| Cwjh.Tv Ltd | Information & communication | 2019 |
| Cwns Limited | Information & communication | 2015 |