| Clayzer Ltd | Brixham | 2017 |
| CLB Management Limited | Marston Moretaine | 2010 |
| CLB Music Ltd | Sheffield | 2022 |
| CLB Music Services Limited | Wolverhampton | 2021 |
| CLB Online Ltd | Prestatyn | 2025 |
| CLC Orchestral Promotions Limited | New Malden | 2017 |
| CLC Studio Ltd | Oldham | 2025 |
| CLD Sport Ltd | Gloucester | 2023 |
| Clea Creates Ltd | London | 2023 |
| Clean Break Productions Limited | London | 2015 |
| Clean Court Architecture Limited | London | 2025 |
| Clean Earth Construction Ltd | Colchester | 2022 |
| Clean Earth Limited | Colchester | 1998 |
| Clean Energy Recruitment Ltd | Grimsby | 2020 |
| Clean Ocean Festival Ltd | North Berwick | 2019 |
| Clean Stack Poker Ltd | London | 2026 |
| Cleangreen Ltd | Birmingham | 2003 |
| Cleanslate F.C. C.I.C. | Milton Keynes | 2013 |
| Clear and Loud Limited | Newcastle Upon Tyne | 2013 |
| Clear Bright Things Limited | Dunoon | 2025 |
| Clear Canvas Collective C.I.C. | Hove | 2026 |
| Clear Choice Cleaning & Maintenance Limited | Cardiff | 2008 |
| Clear Competitions Ltd | Birmingham | 2026 |
| Clear CUT Academy Ltd | London | 2017 |
| Clear Design UK Limited | Bristol | 2002 |
| Clear Frame Locations Ltd | London | 2024 |
| Clear Graphics Limited | Norwich | 1991 |
| Clear Light Records Limited | London | 2018 |
| Clear Line Studios Limited | Weston-Super-Mare | 2023 |
| Clear Motion Sports Ltd | Manchester | 2024 |
| Clear Productions Limited | London | 1989 |
| Clear Sense Technologies Limited | Bishop'S Stortford | 2023 |
| Clear Synergy Ltd | Chislehurst | 2018 |
| Clear to Hear Limited | Ilford | 2012 |
| Clear Wave Music Ltd | Llanharan | 2012 |
| Clearcut Arts Limited | Southwick | 2017 |
| Clearcut Golf Limited | Marlow | 2021 |
| Cleared for Films Limited | London | 2024 |
| Clearforce Limited | Stockport. | 1988 |
| Clearhill Enterprises Limited | Banbridge | 1992 |
| Clearpine Developments Limited | Nuneaton | 1989 |
| Clearview Capital Bidco Limited | Cardiff | 2024 |
| Clearview Cattery (Hapton) Limited | Accrington | 2020 |
| Clearwater Angling Club Limited | London | 2026 |
| Clearwater Casino Consultancy Limited | Crowthorne | 1999 |
| Clearwater Media Ltd | Hassocks | 2019 |
| Clearwater Paddling Limited | Oban | 2011 |
| Clearwave Productions Ltd | Llanharan | 2014 |
| Clearwell Mine Management Limited | Gloucs. | 1995 |
| Cleary's Boxing Management Ltd | Southam | 2024 |
| Cleave Fine Art Limited | Peterborough | 2009 |
| Cleaver Squash Limited | Nuneaton | 1978 |
| Cleckheaton & District Golf Club Limited(The) | | 1920 |
| Cleckheaton Folk Festival Organisation | Cleckheaton | 2004 |
| Cleckheaton Sports Club Ltd | Cleckheaton | 2025 |
| Cleckheaton Virtual Golf Centre Limited | Cleckheaton | 2017 |
| Clee Bowls Club Ltd | Cleethorpes | 2022 |
| Clee Fields Management Company Limited | North East Lincolnshire | 2001 |
| Clee Hill Rugby Football Club Limited | Ludlow | 2012 |
| Cleethorpes and District Swimming Club Limited | Grimsby | 2019 |
| Cleethorpes Bowling Club Limited(The) | North East Lincolnshire | 1908 |
| Cleethorpes Cricket Club Limited | Cleethorpes | 2016 |
| Cleethorpes Gathering Ltd | Manchester | 2018 |
| Cleethorpes Golf Club (1894) Limited | Cleethorpes | 2004 |
| Cleethorpes Rugby Union Football Club Limited | Humberston | 2009 |
| Cleeton MX Ltd | Kidderminster | 2024 |
| Cleeve Racing Limited | Belfast | 2011 |
| Clegg Solutions Limited | Hereford | 2013 |
| Clemens Enterprises Limited | London | 1959 |
| Clements Entertainment Limited | Kington | 2021 |
| Clements Hall Trust | York | 2000 |
| Clements Music Ltd | Welwyn | 2025 |
| Clemms Ltd | London | 2025 |
| Clems Haus Ltd | Rochester | 2025 |
| Cleo Studios Ltd | London | 2025 |
| Cleobury Mortimer Rugby Football Club Limited | Kidderminster | 2012 |
| Cleobury Mortimer Sports and Social Club | Kidderminster | 1991 |
| Cleopatra Music Ltd | London | 2015 |
| Cleopatra Productions Ltd | London | 2023 |
| Clermont Leisure (UK) Limited | Manchester | 2005 |
| Clevans Music Limited | Dunfermline | 2017 |
| Cleve Archers Limited | Bristol | 2015 |
| Clevedon Arena Ltd | Clevedon | 2009 |
| Clevedon Golf Club Limited | Clevedon | 2001 |
| Clevedon Gymnastics Centre C.I.C. | Clevedon | 2014 |
| Clevedon Lawn Tennis Club Limited | Clevedon | 2005 |
| Clevedon Pier and Heritage CIC | Clevedon | 1983 |
| Clevedon Railways Limited | Clevedon | 2013 |
| Clevedon RFC Trading and Supporters Group Limited | Clevedon | 2016 |
| Clevedon Sailing Club Ltd | Clevedon | 2019 |
| Clevedon Town FC Ltd | London | 2026 |
| Cleveland Anderson International Artists Ltd | Greenford | 2011 |
| Cleveland Auto & Marine Limited | Aldershot | 1999 |
| Cleveland Boxing Club CIC | Stockton | 2024 |
| Cleveland House Stud Limited | Newmarket | 2014 |
| Cleveland Independent Theatre Company Limited | Darlington | 1979 |
| Cleveland Leisure Centres Limited | Middlesbrough | 1973 |
| Cleveland Model Railway Club | Saltburn By The Sea | 2010 |
| Cleveland Pools Trust | Bath | 2005 |
| Clever Cubs Club Ltd | London | 2025 |