| Churchill Management (Skegness) Company Limited | Real estate | 2019 |
| Churchview Management Company (Skegness) Limited | Real estate | 2016 |
| Circ Ltd. | Professional & scientific | 2024 |
| CJH Plant and Tool Hire Limited | Extraterritorial | 2015 |
| CJO Electrical Services Ltd | Construction | 2022 |
| CJS Taxi Skegness Ltd | Transport & logistics | 2021 |
| CJW Holdings (Skegness) Limited | Financial services | 2026 |
| CKF Goldenyears Domiciliary Care Ltd | Health & social care | 2025 |
| Claimant Costs Recovery (North ) Ltd | Professional & scientific | 2012 |
| Clar Furniture Limited | Manufacturing | 2021 |
| Clarendon Hotel (Skegness) Ltd | Hospitality | 2007 |
| Clark Dental Studio Limited | Health & social care | 2010 |
| Classic Coffee Shop Ltd | Hospitality | 2013 |
| Classy Products Limited | Real estate | 1973 |
| Cleaning Facility Service Ltd | Administrative & support | 2018 |
| Cleanova 1982 Ltd | Administrative & support | 2026 |
| Clear Core Trading Ltd | Wholesale & retail | 2026 |
| Clemco Limited | Hospitality | 2003 |
| Click INK Limited | Manufacturing | 2016 |
| Click IT Health Limited | Information & communication | 2021 |
| Cloud Connect Online Ltd | Information & communication | 2023 |
| Clover Investments (Lincolnshire) Limited | Financial services | 2009 |
| CM Bioceramics Limited | Health & social care | 2025 |
| CNC Plates Ltd | Wholesale & retail | 2024 |
| CNF 21 Ltd | Transport & logistics | 2021 |
| Co Prom Limited | Wholesale & retail | 2003 |
| Coach House Management Company (Skegness) Limited | Real estate | 2016 |
| Coast & County Electrical Distributors Limited | Wholesale & retail | 2004 |
| Coastal Accomodation Limited | Hospitality | 2015 |
| Coastal Decks Limited | Construction | 2022 |
| Coastal Electrical Services Lincs Ltd | Construction | 2020 |
| Coastal Properties Lincs Ltd | Real estate | 2023 |
| Coastal Rental Properties Lincs Ltd | Real estate | 2026 |
| Coastal Sheds Limited | Construction | 2021 |
| Coastline Cabs Ltd | Transport & logistics | 2012 |
| Coastline Carpentry Ltd | Construction | 2014 |
| Coastline Futures Ltd | Education | 2026 |
| Coastline Holdings Ltd | Transport & logistics | 2018 |
| Coastline Roofing & Construction Ltd | Construction | 2025 |
| Coco Nyli Ltd | Manufacturing | 2023 |
| Coinsville Ltd | Wholesale & retail | 2016 |
| Collins Social Work Solutions Ltd | Extraterritorial | 2012 |
| Comforts Childcare Ltd | Education | 2010 |
| Commercial DPF Restore Ltd | Wholesale & retail | 2024 |
| CON Serv (Systems) Limited | Construction | 1998 |
| Conroy's Recycling Limited | Water & waste | 2008 |
| Conroys Plant Hire Limited | Administrative & support | 2003 |
| Constans Holiday Ltd | Hospitality | 2021 |
| Constans Inc Ltd | Wholesale & retail | 2015 |
| Constans Tax & Accounting Ltd | Professional & scientific | 2026 |
| Construction ALL Ltd | Construction | 2023 |
| Consulting Suppliers Ltd | Wholesale & retail | 2024 |
| Contempo Dentcare Ltd | Health & social care | 2022 |
| Cool Running Properties Ltd | Real estate | 2023 |
| Copes Transport Ltd | Transport & logistics | 2025 |
| Copley Construction Ltd | Construction | 2026 |
| Copper Veins Ltd | Construction | 2009 |
| Cost Chopper Ltd | Wholesale & retail | 2025 |
| Countryside Developments (Lincolnshire) Limited | Administrative & support | 2007 |
| County Care Group Holdings Ltd | Financial services | 2025 |
| County Care Group Limited | Professional & scientific | 2015 |
| County Care Support Limited | Health & social care | 2017 |
| Cpjs Trading Ltd | Wholesale & retail | 2022 |
| Cranwell House Management Company Limited | Real estate | 2015 |
| Creekside Kitchen Ltd | Hospitality | 2024 |
| Crescent Training Ltd | Education | 2023 |
| Crewwise Ltd | Professional & scientific | 2024 |
| Cripsey Catering Ltd | Hospitality | 2023 |
| Cripsey Confectionary Ltd | Wholesale & retail | 2023 |
| Cripsey Retail Limited | Wholesale & retail | 2020 |
| Cristina Motatu Stanescu Limited | Health & social care | 2014 |
| Croftmarsh Developments Head Co Limited | Construction | 2025 |
| Croftmarsh Limited | Agriculture & fishing | 1978 |
| Crow Financial Advice Limited | Financial services | 2023 |
| Crystaldean Limited | Real estate | 1999 |
| Ctrl ALT Design & Graphics Ltd | Professional & scientific | 2026 |
| Cutting Crew (Boston) Limited | Other services | 2005 |
| Cuttingedgecrafts.Co.Uk Ltd | Extraterritorial | 2007 |
| D and T Properties Limited | Real estate | 2019 |
| D Butler Scaffolding Ltd | Construction | 2025 |
| D C Watts Limited | Hospitality | 2015 |
| D Oakley Electrical Services Ltd | Construction | 2017 |
| D&D Gifts Limited | Wholesale & retail | 2025 |
| D. J. + J. E. White (AP) Limited | Arts & recreation | 2012 |
| DAB Industries Ltd | Wholesale & retail | 2023 |
| DAJ Catering Limited | Hospitality | 2022 |
| Dale House Management (Tetford) Limited | Households | 2018 |
| Dallster Limited | Wholesale & retail | 2021 |
| Daubney Solutions Ltd. | Wholesale & retail | 2023 |
| Dave Evans Electrical Limited | Construction | 2017 |
| David Dental Solutions Limited | Health & social care | 2021 |
| Davie Family Limited | Agriculture & fishing | 2009 |
| Dawlett Ltd | Hospitality | 2021 |
| DC MED Ltd | Health & social care | 2023 |
| Dean Halliday Painter & Decorator Ltd | Construction | 2020 |
| DEAS1990 Limited | Transport & logistics | 2024 |
| Deck Supermarket Limited | Wholesale & retail | 2013 |
| Delaney Product Sale Ltd | Wholesale & retail | 2026 |
| Delta Payroll Ltd | Administrative & support | 2013 |
| Dennis Maltby Limited | Wholesale & retail | 1976 |