| Creative Function Ltd | Professional & scientific | 2014 |
| Creative Glass & Design Ltd | Construction | 2022 |
| Creative Media Network | Education | 2014 |
| Creative Sound Design Limited | Arts & recreation | 2008 |
| Credence Private Limited | Wholesale & retail | 2025 |
| Credit Merchant Solutions Ltd | Financial services | 2020 |
| Crehana Education Limited | Education | 2016 |
| Crendon House (Amersham) Management Company Limited | Real estate | 2006 |
| Crendon House Lettings Limited | Real estate | 2020 |
| Crescent Beach Limited | Professional & scientific | 2019 |
| Cressex Day Nursery Limited | Education | 2010 |
| Cressex Insurance Services Limited | Financial services | 2009 |
| Cressex Practice Limited | Health & social care | 2019 |
| Cressexbuildingservice Ltd | Construction | 2024 |
| Crichlow Consultancy Ltd | Information & communication | 2013 |
| Cricket School of Excellence Limited | Education | 2024 |
| Crimson Lake Ancillary Service Providers Limited | Administrative & support | 2019 |
| Crisp and Melt Ltd | Hospitality | 2025 |
| Crispin Property Investments Ltd | Real estate | 2015 |
| Crissy & Maya Delivery Ltd | Transport & logistics | 2025 |
| Criterion Studios Ltd | Information & communication | 2020 |
| Critical Airflow Controls Limited | Professional & scientific | 2024 |
| Critical Airflow Europe Limited | Construction | 2013 |
| Critical Data Centre Solutions Limited | Construction | 2017 |
| Croft Trading Limited | Extraterritorial | 1999 |
| Crompton Hall Freeholders Company Limited | Real estate | 2011 |
| Crompton Hall Residents Company Limited | Households | 2004 |
| Cross Hair Property Maintenance Limited | Construction | 2025 |
| Crossco (820) Limited | Professional & scientific | 2004 |
| Crotty Limited | Administrative & support | 2009 |
| Crowden Coachworks Limited | Wholesale & retail | 2008 |
| Crown Chiropractic Limited | Health & social care | 2023 |
| Crown Entertainment Limited | Arts & recreation | 2023 |
| Crown Ghee Limited | Wholesale & retail | 2025 |
| Crown Hotel Blockley Limited | Hospitality | 2021 |
| Crowne Services Ltd | Transport & logistics | 2016 |
| Crownfield Estates Limited | Real estate | 2012 |
| Crownwell Holdings Ltd | Financial services | 2025 |
| Crowthers Consultants Ltd | Construction | 2007 |
| Crpg Real Estate Limited | Construction | 2024 |
| CRS Building Supplies Limited | Wholesale & retail | 2005 |
| CRS Properties Limited | Real estate | 2012 |
| Crumbs and Brownies Ltd | Wholesale & retail | 2022 |
| Crumbs Corner Ltd | Hospitality | 2019 |
| CRUMBS26 Ltd | Hospitality | 2026 |
| CRY GOD 4 Harry Limited | Extraterritorial | 2016 |
| Crystal Bodyshop HW Ltd | Wholesale & retail | 2026 |
| Crystal Bodyshop Ltd | Wholesale & retail | 2025 |
| Crystal Care Home Cleaning Ltd | Administrative & support | 2026 |
| Crystal Cleaning Care HW Ltd | Administrative & support | 2026 |
| Crystal Property Staging Ltd | Professional & scientific | 2022 |
| Crystall Limited | Hospitality | 2016 |
| Crystalmist Ltd | Health & social care | 2011 |
| CS Spedition Ltd | Transport & logistics | 2025 |
| CSD20 Ltd | Real estate | 2023 |
| CSE Industrial Electrical Distributors Limited | Wholesale & retail | 2010 |
| CSE Rail Limited | Professional & scientific | 2004 |
| Csra Limited | Professional & scientific | 2018 |
| Csrw TM Ltd | Construction | 2017 |
| Cssc Enterprises Limited | Professional & scientific | 1999 |
| Cssc Properties Limited | Real estate | 1999 |
| CST Global Limited | Information & communication | 2013 |
| CST IT Services Limited | Information & communication | 2015 |
| Csth Limited | Arts & recreation | 2019 |
| Cstuk Limited | Information & communication | 2018 |
| CSW Technical Services Limited | Administrative & support | 2003 |
| CT Electrical & Building Services Limited | Construction | 2021 |
| CTV Outside Broadcasts Limited | Information & communication | 2005 |
| Cubitts Cabins & Modular Buildings Ltd | Construction | 2018 |
| CUE Graphics Limited | Information & communication | 2022 |
| Culture Works Consortium Ltd | Professional & scientific | 2020 |
| Cupcake Kangaroo Ltd | Arts & recreation | 2025 |
| Cupertino Group Ltd | Professional & scientific | 2020 |
| Cuppa Club Maidenhead Ltd | Hospitality | 2019 |
| Cuppa Club Retail Ltd | Wholesale & retail | 2021 |
| Cura Therapy Ltd | Arts & recreation | 2025 |
| Curabridge Realty Limited | Real estate | 2022 |
| Curious Kiwi Ltd | Information & communication | 2022 |
| Curl Design Ltd | Construction | 2012 |
| Curls & Bubbles Ltd | Wholesale & retail | 2025 |
| Curry HUT Catering Ltd | Real estate | 2017 |
| Cursive Studio Ltd | Professional & scientific | 2021 |
| Curtis Steel Limited | Professional & scientific | 2005 |
| Curtsons (Radstock) Limited | Professional & scientific | 2007 |
| Curzon Solicitors Limited | Professional & scientific | 2016 |
| Cushdeee Limited | Manufacturing | 2006 |
| Cusp Digital Ltd | Information & communication | 2025 |
| Custom Everything Ltd | Wholesale & retail | 2025 |
| Custom Floors Limited | Construction | 2013 |
| Customer Service Insight Limited | Information & communication | 1998 |
| Cutting Edge Landscapes Ltd | Administrative & support | 2025 |
| CVP Investments Ltd | Real estate | 2025 |
| CW GAS & Heating Services Ltd | Construction | 2021 |
| CWA Studios Limited | Professional & scientific | 2003 |
| CWD Finance Limited | Professional & scientific | 2024 |
| CWM Gelli (Blackwood) Residents Management Company Ltd | Households | 2022 |
| CWS Mortgage Services Ltd | Financial services | 2019 |
| CWS Property Services Ltd | Real estate | 2020 |
| CX Factor Ltd | Professional & scientific | 2018 |
| Cyber Store Central Ltd | Wholesale & retail | 2024 |