| Christ the Hope of Glory Evangelical Church | Other services | 2011 |
| Christ Vision Sanctuary International Limited | Other services | 2023 |
| Christal Solutions Ltd | Transport & logistics | 2004 |
| Christianuyi Limited | Professional & scientific | 2007 |
| Chroma Events Limited | Professional & scientific | 2024 |
| Chromatography LAB Consultancy Ltd | Professional & scientific | 2025 |
| Chuckery Automotives Ltd | Other services | 2017 |
| Chuckery Cafe Limited | Hospitality | 2018 |
| Chukschi Logistics Limited | Transport & logistics | 2025 |
| Chunky Chicken Ltd | Hospitality | 2026 |
| Church Street Healthcare Limited | Wholesale & retail | 2011 |
| Churchfield Education Products Limited | Manufacturing | 2016 |
| Churchill Home Services Ltd | Administrative & support | 2007 |
| Churchills Winning Concepts Limited | Extraterritorial | 2012 |
| Chy-Har Ltd | Hospitality | 2020 |
| CIB Design & Build Ltd | Construction | 2015 |
| Ciic Infotech Limited | Information & communication | 2024 |
| Ciic IT Solutions Limited | Information & communication | 2024 |
| Cinematic Post Solutions Limited | Information & communication | 2025 |
| Cini Ltd | Real estate | 2017 |
| Cinnamon Court Food Group Ltd | Hospitality | 2023 |
| Circadiem PTY Ltd | Wholesale & retail | 2026 |
| Circle of Life Training Ltd | Education | 2022 |
| Circle Stack Limited | Information & communication | 2022 |
| Circuit Coatings (Automotive) Limited | Administrative & support | 2012 |
| Circuit Coatings (Holdings) Limited | Administrative & support | 2016 |
| Circuit Coatings Limited | Administrative & support | 1979 |
| Circumference Wheels Ltd | Wholesale & retail | 2020 |
| City & Country Associates Limited | Real estate | 2001 |
| City & Nationwide Recruitment Ltd | Administrative & support | 2015 |
| City & Nationwide Recruitment Solutions Limited | Financial services | 2024 |
| City Business Link Limited | Transport & logistics | 2023 |
| City Coach Hire Ltd | Transport & logistics | 2023 |
| City Dobbs Street Ltd | Transport & logistics | 2025 |
| City Home Contracrtors Ltd | Construction | 2019 |
| City Properties (WM) Ltd | Real estate | 2022 |
| CJ Rail Services Ltd | Construction | 2014 |
| CJC Exchange Limited | Hospitality | 2014 |
| CJC Supplies Ltd | Wholesale & retail | 2023 |
| Cjchalk Ltd | Administrative & support | 2019 |
| CJL Hughes Scaffolding Ltd | Construction | 2014 |
| CJP Financial Planning Ltd | Financial services | 2013 |
| CJT Pubs and Entertainment Ltd | Hospitality | 2025 |
| CK Motor Traders Ltd | Wholesale & retail | 2023 |
| CKB Consultancy Limited | Health & social care | 2024 |
| Ckbj Ltd | Hospitality | 2024 |
| CKN Accountancy Limited | Professional & scientific | 2015 |
| CKT Trades Ltd | Wholesale & retail | 2021 |
| CL Beauty Aesthetics Ltd | Other services | 2021 |
| Claire Ball Limited | Education | 2022 |
| Clampcrees Ltd | Transport & logistics | 2024 |
| Clarabelleuk Limited | Wholesale & retail | 2025 |
| Clare Locum Services Limited | Health & social care | 2010 |
| Clarence Park Properties Ltd | Real estate | 2025 |
| Claret Enterprises Limited | Hospitality | 2013 |
| Clarity Imaging Investments Ltd | Financial services | 2021 |
| Clarity Imaging Limited | Health & social care | 2017 |
| Clarity News Limited | Extraterritorial | 2025 |
| Clarke Concrete Services Limited | Manufacturing | 2022 |
| Class One Recruitment Services Limited | Administrative & support | 2005 |
| Classic Bitz Ltd | Wholesale & retail | 2025 |
| Classic Furniture Group Limited | Manufacturing | 1971 |
| Classic Physiques Gym Ltd | Arts & recreation | 2018 |
| Classic Pizza PVT Ltd | Hospitality | 2026 |
| Classyium Ltd | Wholesale & retail | 2023 |
| Clavnet Ltd | Information & communication | 2015 |
| Clay and Concrete Construction Materials Limited | Extraterritorial | 1984 |
| Clay and Concrete Sewers Limited | Construction | 1982 |
| Clay Court Services Limited | Construction | 2018 |
| Clayton Brown Limited | Professional & scientific | 2009 |
| CLB IT Consulting Ltd | Information & communication | 2021 |
| CLC Healthcare Ltd | Health & social care | 2020 |
| CLC PUB Company Limited | Hospitality | 2024 |
| CLD Enterprise Ltd | Other services | 2019 |
| Clean & Fresh Services Ltd | Administrative & support | 2020 |
| Clean and Gleam Limited Company Limited | Administrative & support | 2014 |
| Clean Image (UK) Laundry & Drycleaning Services Limited | Other services | 2011 |
| Clean Planet Union CIC | Professional & scientific | 2025 |
| Clean Rescue Limited | Administrative & support | 2014 |
| Cleancous Ltd | Wholesale & retail | 2024 |
| Cleaning With Class Limited | Administrative & support | 2024 |
| CLEANING112 Ltd | Administrative & support | 2025 |
| Cleanse Business Limited | Administrative & support | 2025 |
| Cleanseable Limited | Administrative & support | 2025 |
| Cleany Bins (Walsall) Limited | Administrative & support | 2025 |
| Cleany Bins (West Midlands) Limited | Administrative & support | 2022 |
| Cleany Bins Limited | Administrative & support | 1996 |
| Clear and Clean Services Limited | Other services | 1988 |
| Clear Site Waste and Clearance Ltd | Water & waste | 2026 |
| Clearance Discount Ltd | Wholesale & retail | 2023 |
| Clearance Outlet (Walsall) Ltd | Wholesale & retail | 2023 |
| Clearer Sky Care Ltd | Health & social care | 2010 |
| Clearstone Clean Ltd | Administrative & support | 2026 |
| Clearwave Services Ltd | Information & communication | 2024 |
| Clees Plastics Ltd | Construction | 2023 |
| Cleevewood Pharma Ltd | Wholesale & retail | 2024 |
| Clemson Plumbing & Heating Limited | Construction | 2019 |
| Clerk AI Ltd | Professional & scientific | 2026 |
| Clews & Co Lettings Ltd | Real estate | 2022 |
| Clews Cleaning Services Limited | Administrative & support | 2015 |