| Castle View Tattoo Limited | Arts & recreation | 2024 |
| Castlegate Group Ltd | Information & communication | 2019 |
| Castleview Group Care Limited | Health & social care | 2025 |
| Castleview Group Holdings Limited | Financial services | 2022 |
| Castleview Group Training Limited | Administrative & support | 2001 |
| Catering Units and Van Conversions Limited | Manufacturing | 2021 |
| Caterpillar Club and Bumble Bees C.I.C. | Education | 2006 |
| Cazuela Tapas & Bar Ltd | Hospitality | 2025 |
| CB99 Limited | Professional & scientific | 2018 |
| CC Media Limited | Information & communication | 2025 |
| CCP Holdings NE Ltd | Professional & scientific | 2015 |
| Ccsj Property Limited | Real estate | 2017 |
| CDC Enterprise Agency Limited | Administrative & support | 1987 |
| CDM Developments Ltd | Real estate | 2025 |
| Cdonaldson Marketing Ltd | Professional & scientific | 2024 |
| CDS VAC EX Ltd | Administrative & support | 2018 |
| CEA Civils Ltd | Construction | 2025 |
| Cemor MED Ltd | Professional & scientific | 2010 |
| Cestria Land Limited | Professional & scientific | 2021 |
| Cestria Subsea Limited | Professional & scientific | 2011 |
| Chain Dance Studio Ltd | Arts & recreation | 2025 |
| Changing Tide Training and Employment Services Limited | Education | 2019 |
| Charterglobe Limited | Real estate | 2009 |
| Chefjl Limited | Hospitality | 2025 |
| Chellos Limited | Wholesale & retail | 2000 |
| Chellos Pizzeria Limited | Wholesale & retail | 2024 |
| Cheryl Cairns Limited | Extraterritorial | 2025 |
| Cheryl Moodie Ltd | Extraterritorial | 2025 |
| Chesjp Ltd | Hospitality | 2025 |
| Chester Coffee Ltd | Hospitality | 2025 |
| Chester Health Shop Ltd | Wholesale & retail | 2024 |
| Chester LE Barber Ltd | Other services | 2019 |
| Chester LE Golden FRY Ltd | Hospitality | 2022 |
| Chester LE Street Pals C.I.C. | Other services | 2020 |
| Chester LE Street Primary Care Network Limited | Health & social care | 2019 |
| Chester Metal Fabrications Ltd | Manufacturing | 2005 |
| Chester SHAWARMA1 Ltd | Hospitality | 2025 |
| Chester Town Tyres Ltd | Wholesale & retail | 2003 |
| Chester Vapes Ltd | Wholesale & retail | 2022 |
| Chester-Le-Street Cricket Club Limited | Arts & recreation | 2006 |
| Chilli (Birtley) Ltd | Hospitality | 2024 |
| Chisholm Air Conditioning and Electrical Services Ltd | Manufacturing | 2023 |
| Chris Days Heating Ltd | Construction | 2022 |
| Chris Lamb Will Writing Ltd | Professional & scientific | 2016 |
| Chris Mcardle Roofing Services Ltd | Administrative & support | 2017 |
| Chris Rodgerson Integrity Solutions Limited | Professional & scientific | 2018 |
| Chris Smith Nutrition Limited | Professional & scientific | 2023 |
| Chris Stonock Limited | Real estate | 2007 |
| Chrome Classic Investments Limited | Construction | 2013 |
| CID Architectural Limited | Professional & scientific | 2020 |
| Cirruscommerce Limited | Wholesale & retail | 2025 |
| Citadel Property Company Ltd | Financial services | 2021 |
| CJ Properties NE Limited | Real estate | 2025 |
| CJ Wholesales Ltd | Wholesale & retail | 2025 |
| CK Desserts Ltd | Hospitality | 2026 |
| CL4RK Ltd | Professional & scientific | 2022 |
| Claire Barber PR Limited | Professional & scientific | 2016 |
| Clark Subsea International Ltd | Professional & scientific | 2025 |
| Clean Eats Cuisine Ltd | Hospitality | 2018 |
| Clear Water Flow Limited | Construction | 2022 |
| Clinical Endoscopist Ltd | Health & social care | 2022 |
| Clinical Informatics Consultants Ltd | Information & communication | 2015 |
| Clique Esports Ltd | Professional & scientific | 2019 |
| CLS Clinic Ltd | Health & social care | 2022 |
| CLS Food Company Ltd | Hospitality | 2025 |
| CLS Home Improvements Ltd | Construction | 2026 |
| CLS Vehicle Hire Limited | Administrative & support | 2025 |
| Clsroofing Ltd | Construction | 2025 |
| CLW Site Services Limited | Professional & scientific | 2025 |
| CM Promo Ltd | Professional & scientific | 2024 |
| CMS Healthcare Ltd | Health & social care | 2019 |
| CND Limited | Real estate | 2022 |
| Co Durham Properties Ltd | Construction | 2026 |
| Coaching Centred Leadership Ltd | Professional & scientific | 2020 |
| Coaching for Your Future Limited | Professional & scientific | 2023 |
| Coaction Group Ltd | Construction | 2026 |
| Cochrane Shipbuilders Limited | Energy | 1975 |
| Coffee Rani Ltd | Manufacturing | 2025 |
| Cofiworks(Uk) Ltd | Information & communication | 2021 |
| Coldstream Decorators Limited | Construction | 2017 |
| Colin Pybus Recruitment Ltd | Administrative & support | 2021 |
| Colton Plant & Haulage Ltd | Construction | 2026 |
| Completely Wired Electrical Limited | Construction | 2024 |
| Computer & Laptop Repair Services Limited | Manufacturing | 2013 |
| Computer Centre (Fencehouses) Limited | Wholesale & retail | 2014 |
| Computer Workshop 145 Ltd | Other services | 2024 |
| Connected to Talent Limited | Administrative & support | 2016 |
| Consultive Solutions Limited | Professional & scientific | 2010 |
| Contracts and Consultancy Services (U.K.) Limited | Administrative & support | 1988 |
| Cookson Spice Ltd | Hospitality | 2019 |
| Cosgrove & Dunnett Property Consultants Limited | Households | 2024 |
| Country Live Group Ltd | Arts & recreation | 2026 |
| County Durham Community Projects Ltd | Arts & recreation | 2016 |
| Couzens Cladding Ltd | Construction | 2016 |
| Covaco Limited | Wholesale & retail | 2019 |
| Cowells Construction Ltd | Construction | 2024 |
| CP Vehicle Solutions Ltd | Wholesale & retail | 2023 |
| CPN Developments Limited | Construction | 2018 |
| CPT Drill Ltd | Construction | 2021 |
| CR Inc Limited | Administrative & support | 2003 |