| Camiszon Ltd | Wholesale & retail | 2017 |
| Captivus Ltd | Administrative & support | 2021 |
| Care Home Designs Ltd | Professional & scientific | 2016 |
| Carewhere Limited | Manufacturing | 2006 |
| Cargill Law Limited | Professional & scientific | 2024 |
| Carioca Limited | Information & communication | 2023 |
| Carlton Music Publishers Limited | Financial services | 2018 |
| Carmen Careers Ltd | Professional & scientific | 2026 |
| Carolina Close Freehold Company Limited | Real estate | 2014 |
| Carshare Online Limited | Information & communication | 2001 |
| Carson Stagecraft Ltd | Construction | 2025 |
| Cartridge Shop Amersham Ltd | Wholesale & retail | 2019 |
| Casewise Consulting Limited | Information & communication | 2014 |
| Castell Grove Limited | Real estate | 2018 |
| Castle Electrical Contractors Ltd | Construction | 2020 |
| Castle House Communications Ltd | Information & communication | 2024 |
| Castle Street Liverpool LLP | | 2014 |
| Castlenet Consulting Limited | Professional & scientific | 2017 |
| Catitude Trading Ltd | Wholesale & retail | 2025 |
| Catte Street Limited | Professional & scientific | 2011 |
| Cbltsc Limited | Arts & recreation | 2012 |
| CC in HR Ltd | Administrative & support | 2018 |
| CDM IT Security Controls Limited | Information & communication | 2014 |
| CDS - Car Diagnostic Service Ltd | Wholesale & retail | 2018 |
| Cecil Engineering Installations Limited | Construction | 1982 |
| Cecil Homes Limited | Construction | 1976 |
| Cedar Hills Limited | Real estate | 2018 |
| Cellvance Limited | Professional & scientific | 2025 |
| CEM Bateleur Limited | Administrative & support | 2014 |
| Centile Limited | Professional & scientific | 2021 |
| Centinel Land Limited | Real estate | 2025 |
| Cereda Concrete Service Ltd | Construction | 2019 |
| Certified Associates Ltd | Professional & scientific | 2011 |
| CG Waves Limited | Administrative & support | 2017 |
| CGB Consulting Services Limited | Professional & scientific | 2018 |
| CGS Plumbing & Heating Limited | Construction | 2011 |
| Chaidani Ltd | Hospitality | 2023 |
| Chalfont Classic Cars Limited | Wholesale & retail | 2014 |
| Chalfont Education Limited | Education | 2000 |
| Chalfont Electrical & Property Services Limited | Construction | 2012 |
| Chalfont Tandoori Limited | Hospitality | 2025 |
| Challiscraft Limited | Professional & scientific | 1985 |
| Change Delivered 4 Ltd | Professional & scientific | 2024 |
| Charbelle Ltd | Professional & scientific | 2021 |
| Charles Tait Accounting Limited | Professional & scientific | 2012 |
| Chattertons Limited | Wholesale & retail | 2006 |
| Cherbourg Bakery Ltd | Wholesale & retail | 2024 |
| Cherry Feet Ltd | Health & social care | 2023 |
| Chianti Property Investments Limited | Real estate | 2023 |
| Chica TSN Ltd | Other services | 2025 |
| Chiltern Accountants and Tax Advisors Ltd | Professional & scientific | 2025 |
| Chiltern Architectural Services Limited | Professional & scientific | 2013 |
| Chiltern Architecture Limited | Professional & scientific | 2020 |
| Chiltern Bakehouse Ltd | Manufacturing | 2021 |
| Chiltern Cabinet Limited | Manufacturing | 2025 |
| Chiltern Court Residents Association Limited | Households | 1961 |
| Chiltern Dirt Bikes Limited | Education | 2015 |
| Chiltern Hills Property Limited | Construction | 2024 |
| Chiltern Holiday Cottages Limited | Real estate | 2023 |
| Chiltern Mind Limited | Health & social care | 2008 |
| Chiltern Parade Management Limited | Households | 2006 |
| Chiltern Pizza House Ltd | Hospitality | 2025 |
| Chiltern SME Solutions Ltd | Professional & scientific | 2015 |
| Chiltern Swifts Netball Club Ltd | Arts & recreation | 2023 |
| Chiltern Tuition Ltd | Education | 2024 |
| Choice Money Limited | Financial services | 2010 |
| Christopher Keats Media Limited | Administrative & support | 2015 |
| Chrysalis VCT Admin Limited | Administrative & support | 2007 |
| Church Property Developments Limited | Construction | 2021 |
| CHY Management Company Limited | Households | 2011 |
| Ciao Gelato Limited | Hospitality | 2025 |
| Cipi Limited | Hospitality | 2011 |
| Circle Films Ltd | Information & communication | 2019 |
| Citrus Solutions Limited | Information & communication | 2013 |
| Citygate JHB Limited | Real estate | 2009 |
| Civil and Corporate Security Limited | Real estate | 2006 |
| CJH Media Limited | Professional & scientific | 2016 |
| Claire Barrett Bookkeeping Ltd | Professional & scientific | 2020 |
| Clark Construction (South East) Ltd | Construction | 1999 |
| Clark Contracting Developments Ltd | Construction | 2001 |
| Clark Contracting Ltd | Transport & logistics | 2002 |
| Classic and Custom Works Limited | Wholesale & retail | 2012 |
| Classic Management Services Limited | Real estate | 1980 |
| Clean & Tidy Home Services Ltd | Administrative & support | 2024 |
| Clearvox Communications Ltd | Professional & scientific | 2024 |
| Clever Cowz Ltd | Professional & scientific | 2011 |
| Cliniclink AI Ltd | Information & communication | 2026 |
| Cliniquill Ltd | Professional & scientific | 2025 |
| CLL Technologies Ltd | Information & communication | 2019 |
| CLM Properties Limited | Real estate | 2019 |
| Cloud Alchemy Limited | Information & communication | 2021 |
| Cloud Analogy CRM Specialist Ltd | Information & communication | 2024 |
| Cloud Industry Forum | Information & communication | 2010 |
| Cloud Industry Forum IP Ltd | Information & communication | 2010 |
| Cloudesley Arms Limited | Households | 2000 |
| CMS (Ottershaw) Limited | Real estate | 1999 |
| CMS Aldred Limited | Financial services | 2026 |
| CMS Buckles Limited | Financial services | 2026 |
| CMS Developments Limited | Construction | 2003 |
| CMS Financial Advisory and Consulting Ltd | Professional & scientific | 2026 |