| Clear Ears Clinic Ltd | Health & social care | 2020 |
| Clear Point Capital Ltd | Administrative & support | 2009 |
| Clear Vision Financial Planning Limited | Financial services | 2011 |
| Clearcart Ltd | Wholesale & retail | 2025 |
| Clearhelm Advisory Ltd | Professional & scientific | 2026 |
| Clearlogic Limited | Professional & scientific | 2002 |
| Clearly Inspired Limited | Professional & scientific | 2012 |
| Clearly Secure Enterprises Limited | Wholesale & retail | 2009 |
| Clearmind Health Ltd | Health & social care | 2024 |
| Clearpoint Systems Ltd | Information & communication | 2026 |
| Clearroute Planning Ltd | Professional & scientific | 2025 |
| Clearview Cars Limited | Wholesale & retail | 2025 |
| Clearview Tax Limited | Professional & scientific | 2025 |
| Clearvoice Group Ltd | Professional & scientific | 2018 |
| Clementine Lane Florals Ltd | Wholesale & retail | 2025 |
| Clements Engineering (ST. Neots) Limited | Manufacturing | 1981 |
| Clements Equine Surgery Limited | Professional & scientific | 2020 |
| Clements Marine Limited | Extraterritorial | 2012 |
| Clennam HR Consulting Ltd | Professional & scientific | 2010 |
| Clest Solutions Ltd | Information & communication | 2026 |
| CLG Consultants Limited | Professional & scientific | 1999 |
| Clic Group Ltd | Professional & scientific | 2014 |
| Click Doors (GB) Ltd | Wholesale & retail | 2021 |
| Clickdrive Limited | Education | 2002 |
| CLIK4MORE Ltd | Wholesale & retail | 2024 |
| Climasafe Heating Solutions Limited | Construction | 2021 |
| Clinical 24 Staffing Ltd | Administrative & support | 2014 |
| Clinical Support Services Alliance Limited | Health & social care | 2021 |
| Clinnekt Ltd | Information & communication | 2025 |
| Clinovate Ltd | Wholesale & retail | 2026 |
| Clinserve Consulting Ltd | Professional & scientific | 2019 |
| Clip City Ltd | Other services | 2024 |
| Clipstone Brook Management Company Limited | Households | 2003 |
| Clive Haywood Consulting Limited | Professional & scientific | 2001 |
| Clive Wiley Limited | Real estate | 2005 |
| CLM Auto Limited | Wholesale & retail | 2019 |
| Cloan Industries Limited | Information & communication | 2014 |
| Clock END Limited | Information & communication | 2002 |
| Clock OUT Coffee Limited | Manufacturing | 2024 |
| Clophill Heritage Trust | Hospitality | 2010 |
| Close Connections Limited | Hospitality | 1997 |
| Close Shave Limited | Administrative & support | 2019 |
| Cloud 10 Limited | Professional & scientific | 2010 |
| Cloud Edge Aero Limited | Professional & scientific | 2018 |
| Cloud Estate Holdings Ltd | Financial services | 2025 |
| Cloud Real Estate Ltd | Real estate | 2022 |
| Cloudminds Ltd | Information & communication | 2025 |
| Cloudracex Ltd | Information & communication | 2020 |
| Cloudsman Consulting Ltd | Information & communication | 2025 |
| Cloverleaf Management Company Limited | Households | 2000 |
| CLP Life Ltd | Financial services | 2023 |
| Club 2000 Bingo Limited | Arts & recreation | 2005 |
| Club Lewsey Sports Bar Ltd | Hospitality | 2026 |
| Club Monáe Ltd | Wholesale & retail | 2023 |
| Club Nook Limited | Administrative & support | 2020 |
| Club Towers Limited | Arts & recreation | 2015 |
| Clydes Minibuses Ltd | Transport & logistics | 2010 |
| CM Heating & Maintenance Ltd | Construction | 2023 |
| CM Scullion Associates Ltd | Construction | 2009 |
| CM Shine Ltd | Wholesale & retail | 2023 |
| CMB @ HR Consulting Limited | Professional & scientific | 2009 |
| CMC Plumbing Heating & Bathrooms Ltd | Construction | 2023 |
| Cmd-J Limited | Professional & scientific | 2022 |
| CMF Electrical Contractors Ltd | Construction | 2019 |
| CMF Global Ltd | Administrative & support | 2022 |
| CMG Sports Ltd | Professional & scientific | 2021 |
| CMJ Electrical Ltd | Construction | 2024 |
| Cmld Properties Limited | Real estate | 2018 |
| CMS Consultancy Services Limited | Professional & scientific | 2023 |
| CMW Group Ltd | Construction | 2026 |
| CNC Tooling Limited | Wholesale & retail | 2016 |
| Cncaccounts Limited | Professional & scientific | 2021 |
| Cndg Car Wash Limited | Administrative & support | 2024 |
| CNK Construction Limited | Construction | 2011 |
| Co-Lab Digital Solutions Limited | Information & communication | 2024 |
| Coach Curran Ltd | Health & social care | 2025 |
| Coach House Mews (Arlesey) Limited | Households | 2011 |
| Coach House Mews (Bedford) Management Company Ltd | Households | 2019 |
| Coach ME HOW Limited | Professional & scientific | 2017 |
| Coachingcloud Limited | Extraterritorial | 2011 |
| Coachx Ltd | Transport & logistics | 2024 |
| Coastal Investments Direct Ltd | Professional & scientific | 2012 |
| Coating Processes Limited | Professional & scientific | 2012 |
| Coconut Coast Imports Limited | Wholesale & retail | 2024 |
| Cocun Limited | Health & social care | 2026 |
| Coda Incorporated Ltd | Information & communication | 2024 |
| Codacoda Ltd | Real estate | 2024 |
| Code of Honour Ltd | Information & communication | 2025 |
| Code Tone Studio Limited | Information & communication | 2025 |
| Codesmith Tech Ltd | Information & communication | 2017 |
| Codgold Limited | Households | 1973 |
| Coffee Mart Ltd | Hospitality | 2023 |
| Coffee With Art Ltd | Wholesale & retail | 2013 |
| Coffee Xpress (Bedford) Limited | Wholesale & retail | 2001 |
| Cofferidge Close Limited | Real estate | 2023 |
| Cognate Capital Ltd | Financial services | 2023 |
| Cognisco Limited | Information & communication | 1998 |
| Cognisco Overseas Limited | Information & communication | 2008 |
| Cognisco Systems Limited | Information & communication | 2008 |
| Cognitive Innovation LAB Ltd | Professional & scientific | 2024 |