| Chromolume Tours Ltd | Arts & recreation | 2024 |
| Church Lane Development Company Limited | Households | 2006 |
| Church Lane Humberston Limited | Construction | 2017 |
| Church Road Dental and Cosmetics Ltd | Health & social care | 2012 |
| Church Road Lettings Limited | Real estate | 2019 |
| Churchcrown Builders Limited | Construction | 1992 |
| Ciasen Holdings Limited | Financial services | 2022 |
| Cindy Nails Cleethorpes Ltd | Other services | 2024 |
| CINEMA101 Ltd | Extraterritorial | 2018 |
| Circular Inks Ltd | Manufacturing | 2020 |
| CIS PM Ltd | Administrative & support | 2018 |
| Citipoint Ltd | Real estate | 2015 |
| Citiprint Ltd | Manufacturing | 2016 |
| City Church (Great Grimsby & North East Lincolnshire) | Other services | 2009 |
| Civilwise Engineering Ltd | Professional & scientific | 2025 |
| Ciwells Ltd | Professional & scientific | 2025 |
| CJ Daddy Decorators Limited | Construction | 2018 |
| CJ Heating Engineer Ltd | Construction | 2019 |
| CJ Project Engineering Ltd | Administrative & support | 2021 |
| Cjal Consultants Limited | Professional & scientific | 2014 |
| CJC Interior Solutions Limited | Wholesale & retail | 2012 |
| CJC Software Limited | Information & communication | 1998 |
| CJS Motor Services Ltd | Wholesale & retail | 2025 |
| CJT Rope Access Solutions Limited | Construction | 2018 |
| CJW Interiors Ltd | Construction | 2017 |
| Cjwdev Limited | Wholesale & retail | 2012 |
| CK Accountancy Services (Grimsby) Limited | Professional & scientific | 2012 |
| CL Fish Limited | Financial services | 2020 |
| Clad Spec Limited | Construction | 2016 |
| Clainy's Ltd | Wholesale & retail | 2002 |
| Claire Booth Training Limited | Arts & recreation | 2021 |
| Claire Parker Limited | Professional & scientific | 2012 |
| Clarence Partners Ltd | Real estate | 2026 |
| Clarity Accounting Services Limited | Professional & scientific | 2019 |
| Clark Taverns Ltd | Hospitality | 2024 |
| Clarkes of Lincolnshire Building Services Limited | Construction | 2017 |
| Clarkeson Recycling Limited | Water & waste | 2006 |
| Clas Ropes & Rigging (UK) Limited | Wholesale & retail | 2019 |
| Class Riverside Ltd | Arts & recreation | 2018 |
| Classic Property Developments Limited | Construction | 2017 |
| Classic Windows & Doors Limited | Other services | 2022 |
| Classroom Connect Group Ltd | Administrative & support | 2024 |
| Clayden Engineering Limited | Wholesale & retail | 1977 |
| Clean 'N' Jerk Limited | Manufacturing | 2024 |
| Clean Chic Ltd | Households | 2015 |
| Clean Energy Limited | Wholesale & retail | 2023 |
| Clean Energy Recruitment Ltd | Arts & recreation | 2020 |
| Cleanedrite Network Services Limited | Health & social care | 2011 |
| Cleaning Archie Ltd | Administrative & support | 2024 |
| Clear Choice Windows & Maintenance Ltd | Other services | 2015 |
| Clear View Testing Limited | Professional & scientific | 2021 |
| Clee Auto Centre Limited | Wholesale & retail | 1997 |
| Clee Car Care Limited | Wholesale & retail | 2003 |
| Clee Country Limited | Administrative & support | 2025 |
| Clee Developments Limited | Real estate | 2013 |
| Clee Kids Club CIC | Transport & logistics | 2017 |
| Clee Marine Consultancy Ltd | Professional & scientific | 2023 |
| Clee Metals Limited | Water & waste | 2012 |
| Clee Properties Limited | Real estate | 2013 |
| Clee Renovations Limited | Construction | 2024 |
| Clee Tree Services Limited | Agriculture & fishing | 2019 |
| Cleethorpes and District Swimming Club Limited | Arts & recreation | 2019 |
| Cleethorpes Coastal Collective CIC | Health & social care | 2025 |
| Cleethorpes Container Storage Ltd | Real estate | 2013 |
| Cleethorpes Court Management Company Limited | Administrative & support | 2011 |
| Cleethorpes Holidays Limited | Hospitality | 2014 |
| Cleethorpes Lettings Limited | Hospitality | 2018 |
| Cleethorpes Motors Limited | Wholesale & retail | 2020 |
| Cleethorpes Properties Limited | Construction | 1977 |
| Cleethorpes Serviced Accommodation Ltd | Hospitality | 2000 |
| Cleethorpes Street Food Company Limited | Hospitality | 2018 |
| Cleewold Limited | Professional & scientific | 2024 |
| Click and Jump Limited | Extraterritorial | 2006 |
| Client Review Limited | Professional & scientific | 2008 |
| Clifford United Limited | Hospitality | 2025 |
| Climate and Power Limited | Manufacturing | 2010 |
| Climatemaster Limited | Manufacturing | 1977 |
| Climb 4 Limited | Education | 2013 |
| Clinical Services With Sarah Ltd | Health & social care | 2023 |
| Clintech Safety Consultants Ltd | Administrative & support | 2025 |
| Clive Thornley Consulting Ltd | Professional & scientific | 2024 |
| Cllb Process HSE Ltd | Mining & quarrying | 2026 |
| CLM Precision Ltd | Professional & scientific | 2023 |
| Clmt Developments Limited | Real estate | 2026 |
| Clockwork Communications Ltd | Professional & scientific | 2018 |
| Cloud Beans Limited | Professional & scientific | 2024 |
| Clova Morr Development Limited | Construction | 2019 |
| Club 1000 Limited | Arts & recreation | 2018 |
| Club Barber (Grimsby) Limited | Other services | 2023 |
| Club Barber Limited | Other services | 2019 |
| CMA Restoration Limited | Other services | 2006 |
| CMA Systems Limited | Professional & scientific | 2015 |
| Cmacc Ltd | Administrative & support | 2025 |
| CMC Inspection Ltd | Professional & scientific | 2018 |
| Cmcm Construction Limited | Administrative & support | 2014 |
| CMF Haulage Limited | Transport & logistics | 2026 |
| CMF Riggers Ltd | Information & communication | 2019 |
| CMF Serv Ltd | Construction | 2019 |
| CMV Remarketing Ltd | Wholesale & retail | 2017 |
| Cnci Consultancy Limited | Professional & scientific | 2015 |