| Brighter Manufacturing Limited | Manufacturing | 1999 |
| Brighter Manufacturing Trustees Limited | Administrative & support | 2024 |
| Brit Wholesale Ltd | Wholesale & retail | 2015 |
| Britbyte Limited | Information & communication | 1998 |
| British Animal Rescue and Trauma Care Association CIC | Education | 2012 |
| Bromsberrow Books Limited | Information & communication | 2026 |
| Brookes Clothing Company Limited | Wholesale & retail | 2013 |
| Brown's (Thame) Limited | Wholesale & retail | 2009 |
| BSA Chesters Limited | Professional & scientific | 2000 |
| Bstk Limited | Administrative & support | 2000 |
| Bubblewrap After School Club Ltd | Health & social care | 2015 |
| Buchanan House Management Company Ltd | Real estate | 2023 |
| Bucks Commercial Flooring Limited | Construction | 2021 |
| Bucks Gym Services Limited | Manufacturing | 2021 |
| Burnswood Limited | Real estate | 2021 |
| BY Vicki Limited | Manufacturing | 2025 |
| C.E.M. Thames Valley Limited | Administrative & support | 2003 |
| C6 Solutions Limited | Professional & scientific | 2025 |
| CA Country Homes Limited | Real estate | 2025 |
| Caledonian LC Ltd | Extraterritorial | 2007 |
| Calzada Media Limited | Information & communication | 2011 |
| Cancer Ninjas Limited | Professional & scientific | 2017 |
| Career Mentor Limited | Education | 2013 |
| Carevue Ltd | Information & communication | 2026 |
| Carington Estates Limited | Real estate | 2005 |
| Carnatics Motor Company Limited | Wholesale & retail | 2012 |
| Carrington Crescent Catering Ltd | Hospitality | 2008 |
| Carte Blanche Properties Limited | Hospitality | 2024 |
| Carte Blanche Ventures Holdings Ltd | Professional & scientific | 2011 |
| Carte Blanche Ventures Ltd | Arts & recreation | 2008 |
| Cathy Evans Coaching Limited | Professional & scientific | 2020 |
| Cathy Wilcox Training Ltd | Professional & scientific | 2012 |
| Change DC Limited | Information & communication | 2012 |
| Chapel House Skincare Limited | Manufacturing | 2019 |
| Chapter Four Productions Limited | Information & communication | 2025 |
| Charis Physiotherapy Services Limited | Health & social care | 2013 |
| Charlence Randall Limited | Wholesale & retail | 2017 |
| Chesby Free Limited | Real estate | 2018 |
| Chesby Limited | Real estate | 2011 |
| Cheverton and Lester Ltd | Other services | 2024 |
| Chiltern Care Services (UK) Limited | Financial services | 2006 |
| Chiltern Care Services Limited | Health & social care | 1997 |
| Chiltern Circuits Limited | Manufacturing | 1981 |
| Chiltern Fitness Ltd | Arts & recreation | 2025 |
| Chiltern Hills Properties Limited | Real estate | 1997 |
| Chiltern Marketing Strategy Limited | Professional & scientific | 2023 |
| Chiltern Technology Solutions Ltd | Information & communication | 2025 |
| Chinnamon Spice Ltd | Hospitality | 2022 |
| Christopher Biss Limited | Professional & scientific | 2013 |
| Classic Yacht Management Ltd | Manufacturing | 2019 |
| Cleanreach Ltd | Professional & scientific | 2025 |
| Clear Car Rental Limited | Administrative & support | 2019 |
| Clientrm Limited | Information & communication | 2023 |
| Clipity Clip Ltd | Extraterritorial | 2008 |
| Clipzonk Ltd | Information & communication | 2014 |
| Clive Glenister Associates Limited | Real estate | 2020 |
| Clubwise Software Limited | Information & communication | 1999 |
| Coach Training Limited | Administrative & support | 2018 |
| COG Capital Limited | Professional & scientific | 2024 |
| Coherence LAB Limited | Professional & scientific | 2019 |
| Coleheath Bottom Wood Limited | Real estate | 2011 |
| College Plantation Strip Company Limited | Extraterritorial | 2011 |
| Colours Training Limited | Health & social care | 2025 |
| Combined Services (GB) Limited | Manufacturing | 1992 |
| Complete Cyber Limited | Information & communication | 2014 |
| Composite Mind Ltd | Extraterritorial | 2007 |
| Concordia Property Limited | Construction | 2024 |
| Consentricare Limited | Information & communication | 2017 |
| Constanze Kubern Limited | Administrative & support | 2011 |
| Consult DLF Ltd | Professional & scientific | 2023 |
| Consulting for YOU Europe Limited | Real estate | 2016 |
| Consulting for YOU Limited | Professional & scientific | 2014 |
| Controlnet Ltd | Information & communication | 2014 |
| Convery Limited | Information & communication | 2020 |
| Cook Piling Limited | Construction | 2022 |
| Cooks Marine Services Limited | Construction | 2021 |
| Cooks Plant Limited | Administrative & support | 2004 |
| Cooper Grant Consulting Ltd | Professional & scientific | 2006 |
| Cooper Ventures Limited | Administrative & support | 2007 |
| Copper Kite UK Limited | Construction | 2016 |
| Cornish Tonic Company Limited | Administrative & support | 2019 |
| Cornwall Food and Farming Show Limited | Administrative & support | 2022 |
| Country Gift Company Ltd | Wholesale & retail | 2022 |
| Countrywide Coaches Limited | Transport & logistics | 2019 |
| Creative Beadcraft Limited | Wholesale & retail | 1976 |
| Crombie 1805 Limited | Wholesale & retail | 2021 |
| Crombie IPR Limited | Professional & scientific | 2021 |
| Cross Kite Limited | Professional & scientific | 2021 |
| Cross Lanes Consulting Ltd | Professional & scientific | 2021 |
| Crossley Consulting Ltd | Professional & scientific | 2021 |
| Crowdfuel Ltd | Hospitality | 2026 |
| Crown Industry Ltd | Wholesale & retail | 2022 |
| Crown Medical Ltd | Health & social care | 2017 |
| Csxl Limited | Professional & scientific | 2018 |
| Csxo Limited | Professional & scientific | 2018 |
| Cultrahr Ltd | Administrative & support | 2023 |
| Curtains & Linens Ltd | Wholesale & retail | 2008 |
| Cutedgebond Ltd | Manufacturing | 2021 |
| Cvlm Ltd | Professional & scientific | 2012 |
| Cyber Sushi Design Limited | Information & communication | 2014 |