| Chicago Time Limited | Hospitality | 2025 |
| Chicbylims Limited | Wholesale & retail | 2026 |
| Chicken & Shawarma Limited | Hospitality | 2020 |
| Chief Connector Ltd | Professional & scientific | 2025 |
| Chiefly Living Limited | Real estate | 2019 |
| Chilborough Farm Limited | Extraterritorial | 1958 |
| Child Learning Limited | Information & communication | 2015 |
| Chilled Direct Distribution Limited | Transport & logistics | 2003 |
| Chiltern Business Facilities Management Limited | Administrative & support | 2010 |
| Chiltern Cooling Limited | Manufacturing | 2015 |
| Chiltern Development Training Limited | Education | 2012 |
| Chiltern Digital Ltd. | Professional & scientific | 2015 |
| Chiltern Distillery Ltd | Manufacturing | 2025 |
| Chiltern Drive (Stokenchurch) Management Company Limited | Households | 2014 |
| Chiltern Electrical Ltd | Construction | 2006 |
| Chiltern Energy Limited | Professional & scientific | 1996 |
| Chiltern Financial Consultants Limited | Financial services | 2015 |
| Chiltern Forest Golf Club Limited | Arts & recreation | 1991 |
| Chiltern Glazing Company Ltd | Extraterritorial | 2013 |
| Chiltern Horticulture Ltd | Administrative & support | 2021 |
| Chiltern House (Aylesbury) RTM Company Limited | Households | 2025 |
| Chiltern Instruments and Gauges Limited | Real estate | 1947 |
| Chiltern Padel Limited | Arts & recreation | 2025 |
| Chiltern Park Recruitment Ltd | Administrative & support | 2009 |
| Chiltern Pine Properties Limited | Real estate | 2024 |
| Chiltern Plumbing & Aerials Ltd | Construction | 2013 |
| Chiltern Secure Shredding Limited | Water & waste | 2009 |
| Chiltern Sports Limited | Wholesale & retail | 2015 |
| Chiltern Vehicle Services Limited | Wholesale & retail | 2018 |
| Chiltern View Auctions Limited | Wholesale & retail | 2018 |
| Chiltern View Limited | Other services | 2018 |
| Chiltern View Plants Ltd | Agriculture & fishing | 2018 |
| Chiltern Water Systems Limited | Water & waste | 2026 |
| Chiltern Way Academy Trust | Education | 2016 |
| Chilterns Neuro Centre Limited | Health & social care | 1988 |
| Chilton Road Abstraction (Pitters Piece) Limited | Households | 1995 |
| Chimes Accountancy Services Limited | Professional & scientific | 2014 |
| China Management Services Limited | Professional & scientific | 2018 |
| Chinese Enterpriser Ltd | Real estate | 2011 |
| Chinnis Consulting Limited | Information & communication | 2016 |
| Chinz Healthcare Ltd | Health & social care | 2015 |
| Chiswick CRT RTM Company Ltd | Households | 2025 |
| Chitrakut Ltd | Real estate | 2025 |
| Chloe's Balloon Stacks Ltd | Wholesale & retail | 2025 |
| Choco Investments Limited | Real estate | 2020 |
| Chohan Accountancy Services Limited | Professional & scientific | 2024 |
| Choice Construction and Carpentry Ltd | Construction | 2020 |
| Choice One Transport Solutions Ltd | Transport & logistics | 2025 |
| Choices 4 ALL Limited | Health & social care | 2019 |
| Cholan Construction Ltd | Construction | 2013 |
| Chomidax Ltd | Transport & logistics | 2025 |
| Choose a Playlist Limited | Other services | 2011 |
| Chorda Limited | Information & communication | 2011 |
| Chovatiya Group Limited | Financial services | 2023 |
| Chris & Powell Electrical Ltd | Construction | 2019 |
| Chris a Brown Mortgage and Protection Limited | Financial services | 2016 |
| Chris Coburn Communications Ltd | Professional & scientific | 2021 |
| CHRISHAR7 Ltd | Administrative & support | 2013 |
| Chrishuryn Ltd | Transport & logistics | 2018 |
| Christ Hope of Glory Ministries | Other services | 2011 |
| Christian and Christiana Ltd | Extraterritorial | 2018 |
| Christtechs Global Services Limited | Real estate | 2021 |
| Chroot Solutions Ltd | Information & communication | 2019 |
| Chrystyn Database Consulting Ltd | Other services | 2019 |
| Chuckies Burgers Ltd | Hospitality | 2021 |
| Chuckies Hot Chicken Ltd | Hospitality | 2025 |
| Church Lane Solar Farm Limited | Energy | 2023 |
| Churchview Barns Limited | Agriculture & fishing | 2021 |
| Churchway House Management Company Limited | Administrative & support | 2000 |
| CHW Wellbeing Acupuncture Clinic Limited | Health & social care | 2024 |
| Ciaa Transport Ltd | Transport & logistics | 2025 |
| Cibola Limited | Information & communication | 2002 |
| Cidrew Limited | Professional & scientific | 2011 |
| Cineworx Ltd | Information & communication | 2023 |
| Cipher UK Property Limited | Administrative & support | 2016 |
| Circuit Edge Tech Ltd | Information & communication | 2026 |
| Ciro (London) Limited | Extraterritorial | 1994 |
| Ciro Pearls Limited | Wholesale & retail | 1998 |
| Citizens Advice Buckinghamshire Ltd | Professional & scientific | 2008 |
| Citizens of the World CIC | Education | 2023 |
| City & Guilds College Association Limited | Professional & scientific | 2018 |
| City Electrical Systems Limited | Construction | 2009 |
| City Wheel Autos Ltd | Wholesale & retail | 2025 |
| Citypal Transport Ltd | Transport & logistics | 2020 |
| Citystream Limited | Transport & logistics | 2025 |
| Citytalk Group Ltd | Information & communication | 2019 |
| Citytalk ICT Ltd | Information & communication | 2024 |
| Citytalk IT Ltd | Information & communication | 2019 |
| Citytalk Security Ltd | Administrative & support | 2005 |
| Ciurenis IT Ltd | Information & communication | 2025 |
| Civitas Legal Ltd | Professional & scientific | 2026 |
| CJ Capital Group Limited | Financial services | 2026 |
| CJ Engineering Holdings Limited | Financial services | 2018 |
| CJ Higgin Services Limited | Construction | 2008 |
| CJ TPI Ltd | Real estate | 2021 |
| CJD Consulting Limited | Professional & scientific | 2019 |
| CJY Services LLP | | 2008 |
| CKC Hosting Ltd | Information & communication | 2025 |
| CL Landscapes & Construction Ltd | Administrative & support | 2026 |
| Clacy and SON Ltd | Administrative & support | 2023 |