| Cleaning Service Solution Ltd | Administrative & support | 2025 |
| Clear Corners Limited | Administrative & support | 2014 |
| Clearconcepts Ltd | Professional & scientific | 2000 |
| Clearview Cleaning Solutions Ltd | Administrative & support | 2009 |
| Clearview Estate & Administration Planning Ltd | Professional & scientific | 2022 |
| Clearview Financial Ltd | Professional & scientific | 2024 |
| Clearview Probate Ltd | Professional & scientific | 2020 |
| Clementine & Mint Ltd | Wholesale & retail | 2021 |
| Clewborough Hill Residents Association Limited | Extraterritorial | 1988 |
| Clifton Nurseries (Holdings) Limited | Professional & scientific | 1950 |
| Clifton Nurseries Limited | Wholesale & retail | 1961 |
| Climate Heating Limited | Construction | 2015 |
| Climatech Air Conditioning Limited | Energy | 2002 |
| Clini Pharma Solutions Limited | Health & social care | 2021 |
| Clip ME Cuter Ltd | Other services | 2024 |
| Clothister ORE Limited | Real estate | 1954 |
| Cloud Bleu Management Services Limited | Real estate | 2016 |
| Club Mulholland Limited | Other services | 2013 |
| Clyde Computing Limited | Information & communication | 1994 |
| CMA Garden Design Ltd | Administrative & support | 2010 |
| CMC Build Ltd | Construction | 2025 |
| CMD IT Services Limited | Information & communication | 2004 |
| Cobb Gate Ventures Ltd | Professional & scientific | 2013 |
| Cobbles and HEM Ltd | Administrative & support | 2024 |
| Cocoro Ltd | Professional & scientific | 2021 |
| Codron Financial Services Ltd | Financial services | 2024 |
| Cody Sports & Social Club Limited | Hospitality | 2022 |
| COG Facility Management Ltd | Construction | 2026 |
| Cole & Mason Limited | Wholesale & retail | 1954 |
| Colemanfea Ltd | Professional & scientific | 2024 |
| Coles Mansell Accountants Limited | Professional & scientific | 2021 |
| Coleville Giffard Residents Association Limited | Other services | 1999 |
| Colin Holmes & Associates (Farnborough) | | 1996 |
| Colin Holmes & Associates and Euro I F a (UK) | | 1995 |
| Colinton Services Limited | Administrative & support | 2009 |
| Collab-It Limited | Information & communication | 2026 |
| Collaboration Homes Ltd | Construction | 2021 |
| Collabtech UK Limited | Information & communication | 2020 |
| Collingwood Place Residents Association Limited | Households | 1982 |
| COM3D Limited | Professional & scientific | 2019 |
| Commercial & Property - by to LET Limited | Real estate | 2026 |
| Commercial Steel Services Ltd | Construction | 2021 |
| Commonhold Surveyors Limited | Professional & scientific | 2026 |
| Commpoli Limited | Information & communication | 2013 |
| Communication Investments Limited | Professional & scientific | 1987 |
| Compact Plant Sales Limited | Extraterritorial | 2016 |
| Companial UK Limited | Wholesale & retail | 2015 |
| Compare the Mortgage Limited | Financial services | 2021 |
| Complete Data Resolution Ltd | Professional & scientific | 2025 |
| Compliance Connextions Limited | Professional & scientific | 2024 |
| Compsoft (Holdings) Limited | Information & communication | 2007 |
| Computer Data Source Europe Limited | Information & communication | 2009 |
| Concorde Memorabilia Limited | Extraterritorial | 1993 |
| Connaught House Bagshot Limited | Real estate | 2025 |
| Connect Search & Selection Group Limited | Administrative & support | 2003 |
| Conrad Villamar Design Limited | Professional & scientific | 2009 |
| Conrec Limited | Administrative & support | 2018 |
| Constance Contracting Ltd | Professional & scientific | 2019 |
| Construction Blockchain Consultancy Ltd | Information & communication | 2020 |
| Consultsafe Ltd | Professional & scientific | 2018 |
| Contact IT Solutions Limited | Information & communication | 2009 |
| Controlexpert UK Limited | Other services | 2017 |
| Controlmyevents.Com Ltd | Information & communication | 2017 |
| Convery Development Limited | Construction | 1984 |
| Cooler Homes Ltd | Construction | 2024 |
| Cooler Offices Ltd | Construction | 2024 |
| Coopers Recruit Ltd | Administrative & support | 2014 |
| Copthall Aldershot Ltd | Households | 2022 |
| Cordusio Ltd | Wholesale & retail | 2021 |
| Corfu Town Ltd | Other services | 2019 |
| Corix Partners Ltd | Administrative & support | 2008 |
| Cornell Bruxham Limited | Extraterritorial | 2002 |
| Cortec LED Limited | Construction | 2016 |
| Cosmin's MOT Limited | Wholesale & retail | 2023 |
| Cosmos Pinnacle House Ltd | Real estate | 2026 |
| Country and Western Property Development Ltd | Construction | 2024 |
| County Secure Limited | Construction | 2019 |
| Courtland Property Management Limited | Real estate | 2000 |
| Cover Point Group Ltd | Wholesale & retail | 2024 |
| Coxbridge Group Limited | Financial services | 2016 |
| CPD Waste Water Ltd | Manufacturing | 2022 |
| CPZ Home Ltd | Real estate | 2026 |
| Crane Patisserie Limited | Manufacturing | 2025 |
| Craven Property Services Limited | Other services | 1995 |
| CRE8 Commercial Interiors Limited | Professional & scientific | 2020 |
| CRE8 Commercial Limited | Construction | 2018 |
| Create Clarity Ltd | Professional & scientific | 2021 |
| Creative Services Hampshire Ltd | Construction | 2015 |
| Creative Start Limited | Information & communication | 2015 |
| Crest Washroom Systems Ltd | Construction | 2007 |
| Cric Consult Ltd | Administrative & support | 2026 |
| Cric Ltd | Health & social care | 2014 |
| Critical Mass Technologies Ltd | Information & communication | 2019 |
| CRL Developments Ltd | Construction | 2016 |
| Croft & Partners Ltd | Other services | 2009 |
| Crondall Builders Limited | Construction | 2013 |
| Crosby Building Services Ltd | Construction | 2001 |
| Cross Property Investments Limited | Real estate | 2017 |
| Crossmoor Aviation Consultants Limited | Professional & scientific | 2019 |
| Crowthorne Cars Ltd | Transport & logistics | 2013 |