| Continental Luxury Limited | Harrogate | 2026 |
| Continental Prestige Limited | Harrogate | 2026 |
| Continental Villas Limited | Basildon | 1982 |
| Continental Wood Limited | Newport | 2024 |
| Continental Wood Products Limited | Newport | 2024 |
| Continest Limited | Hook | 2020 |
| Continu-Forms Holdings PLC | Bath | 1993 |
| Continu-Forms Profit Sharing Scheme Trustees Limited | Radstock | 1999 |
| Continuous Guttering South Coast Limited | Southampton | 2002 |
| Continuum Learning Ltd | London | 2024 |
| Contour Projects Limited | Cumbria | 2007 |
| Contract Ceilings Limited | Belfast | 2012 |
| Contract Hire and Leasing Ltd | Congleton | 2013 |
| Contract Hire Limited | Preston | 2004 |
| Contract Joinery Nwuk Limited | Leigh | 2023 |
| Contract Lifting Services Limited | Halesowen | 2025 |
| Contract Locking Services (Holdings) Limited | Letchworth Garden City | 2008 |
| Contract Nominees Limited | Salford | 2005 |
| Contract Options (T M) Limited | Reading | 2019 |
| Contract Smart Limited | Bournemouth | 2007 |
| Contract-Mattressticking.Co.Uk Limited | Clitheroe | 2014 |
| Contract-Mattressticking.Com Limited | Clitheroe | 2014 |
| Contracthire.Com Ltd | Preston | 2009 |
| Contractor Tracker Limited | Glasgow | 2012 |
| CONTRACTOR4U Ltd | London | 2023 |
| CONTRACTORS4CONTRACTORS Ltd | Bognor Regis | 2026 |
| Contrafox Ltd | Waterlooville | 2019 |
| Contrarian Limited | Slough | 1999 |
| Contreversal Ltd | Woking | 2025 |
| Contribufy Ltd | London | 2017 |
| Contrived Capital Ltd. | Warrington | 2019 |
| Control Flow Technologies Limited | Sunderland | 2020 |
| Control Gear Distributors Ltd. | Hertfordshire | 1987 |
| Control in Motion Limited | Stockport | 2013 |
| Control Trading Limited | Ipswich | 2007 |
| Control Wise Solutions Ltd | Bury St. Edmunds | 2023 |
| Controlled Storage Limited | London | 2015 |
| Controls and Communications Limited | Reading | 1936 |
| Controlshift Ltd | Manchester | 2022 |
| Controtax Ltd | Harrogate | 2022 |
| Conuma Coal Limited | Milton Keynes | 2019 |
| Convene Hospitality Ltd | Ipswich | 2025 |
| Convenience Shops (1) Limited | Manchester | 2018 |
| Convenience Shops (2) Limited | Manchester | 2018 |
| Convenience Store Reit Limited | London | 2012 |
| Convention Services Ltd | Portstewart | 2003 |
| Conventus Technical Solutions Limited | Bristol | 2015 |
| Converged Solutions UK Limited | Eastleigh | 2021 |
| Convergent Holdings (London) Ltd | London | 2011 |
| Convergent Media Solutions Limited | London | 2009 |
| Conversational Accountancy Ltd | Hemel Hempstead | 2023 |
| Conversational Accountants Ltd | Hemel Hempstead | 2023 |
| Converse Communications Ltd | Chandlers Ford | 2015 |
| Conversion LAB Limited | London | 2025 |
| Convert-A-Van Ltd | Redditch | 2014 |
| Convertdata Ltd | Bristol | 2013 |
| Convex Carpentry Limited | Kingston Upon Thames | 2011 |
| Convince Consultancy Limited | Blackheath | 2009 |
| Convity Ltd | Stockport | 2017 |
| Conway Group Ltd. | Co.Londonderry | 1991 |
| Conway Minerals Limited | Sevenoaks | 2025 |
| Conway Motors Limited | Maidstone | 2008 |
| Conwy Consulting Ltd | Llandudno | 2007 |
| Conwy RD Challenger Limited | Salford | 2021 |
| Conwy Valley (Dairy Products) Ltd | Tewkesbury | 2007 |
| Conwy Valley Windows Ltd | Llandudno | 2012 |
| Conx Coffee Ltd | Norwich | 2024 |
| Conxus Ltd | London | 2025 |
| Conyers Co-Operative Limited | London | 2011 |
| Conzept Handyman Limited | London | 2019 |
| Coochie Rhodes Limited | Warminster | 2016 |
| Coocoodolove Ltd | Grays | 2016 |
| Cooee Ltd | London | 2016 |
| Cook & Associates M & E Consultants Limited | Bromley | 2007 |
| Cook (Damp & Decay) Limited | Hull | 2006 |
| Cook Food Limited | Sittingbourne | 1994 |
| Cook Kitchens Limited | Sittingbourne | 2004 |
| Cook OR Burn Limited | London | 2021 |
| Cook Puddings Limited | Sittingbourne | 2006 |
| Cook Retail Limited | Sittingbourne | 1997 |
| Cook Structural Repairs Limited | Hull | 2006 |
| Cooke & Partners Limited | Cardiff | 1991 |
| Cooke Bros Property Limited | | 2009 |
| Cooke Developments Limited | Lancashire | 1999 |
| Cookham Road 1965 Limited | Swindon | 2014 |
| Cookie JAR Limited | Rubery, Birmingham | 1904 |
| Cookology Appliances Limited | Haverhill | 2021 |
| Cookoo App Limited | London | 2021 |
| Cooksey & SON Limited | Sutton Coldfield | 1945 |
| Cooksley & SON Limited | Sutton Coldfield | 1987 |
| Cookson Properties Trading Limited | Knutsford | 2011 |
| Cooksons Accountants Limited | Nottingham | 2002 |
| Cookswood Estate Ltd | Glastonbury | 2014 |
| Cookswood Holiday Retreat Limited | Glastonbury | 2010 |
| Cookswood Rentals Ltd | Glastonbury | 2022 |
| Cook`S Tree Surgeons (Wimbledon) Limited | Morden | 2009 |
| Cool Banana Pictures Ltd | Kington | 2019 |
| Cool Blue Limited | Newcastle Upon Tyne | 2017 |
| Cool Canvas Ltd | Preston | 2011 |
| Cool Cargo Limited | Newmarket | 1995 |