| Catharsis | 1990 | — | — |
| Cats and Cats and Cats | 2005 | — | — |
| Caïna | 2004 | — | black metal / shoegaze / experimental |
| Cease2Xist | 2010 | — | — |
| Ceiling Demons | 27 September 2011 | — | — |
| Celestial Sanctuary | 2019 | — | — |
| Centiment | 2000 | — | — |
| Central Band of the Royal British Legion | 1944 | — | — |
| Centrefolds | 2010 | — | — |
| Chad & Jeremy | 1960 | — | — |
| Chairmen of the Bored | 2011 | — | — |
| Chalk | 2019 | — | — |
| ChameleonsVox | 2009 | — | — |
| Chaos 8 | 2012 | — | — |
| Chaos UK | 1979 | — | — |
| Chariot | 1983 | — | — |
| Charlie Goes Electric | 1 October 2014 | — | — |
| Chelsea | 1976 | — | UK punk band |
| Cherry White | 2010 | — | — |
| Chicken Shack | 1965 | — | — |
| China Crisis | 1979 | — | — |
| China Shop Bull | 11 May 2006 | — | — |
| Christ reflection | 2014 | — | — |
| Christie | 1969 | — | English soft rock band |
| Chron Gen | January 1978 | — | — |
| Church of the Cosmic Skull | 2015 | — | — |
| CHVRCHES | 2011 | — | Glaswegian electronic pop trio |
| Cindytalk | 1982 | — | — |
| Circa Waves | 2013 | — | English indie rock band |
| Citizen Fish | 1990 | — | — |
| Citizens! | 2010 | — | — |
| Class War | 1986 | — | — |
| Claustraphobia | 2001 | — | — |
| Clean Bandit | 2008 | — | — |
| Clear Blue Sky | 1968 | — | — |
| Clearlake | January 2000 | — | — |
| Cleavers | 2011 | — | — |
| Click Click | 1982 | — | — |
| Climax Blues Band | 1968 | — | — |
| Clinic | 1997 | — | UK rock band |
| Clock DVA | 1978 | — | — |
| Cloven Hoof | 1979 | — | — |
| Cock Sparrer | 1972 | — | — |
| Cockney Rejects | 1978 | — | — |
| Code | 2002 | — | black metal/progressive metal from UK |
| Coded Marking | 2021 | — | — |
| Coffin Mulch | 2018 | — | — |
| Cognizance | 2012 | — | — |
| Cold Crypt | 2012 | — | — |
| Cold in Berlin | 2010 | — | — |
| Coldplay | September 1996 | — | — |
| Collapsed Lung | 1992 | — | — |
| Colosseum | 1968 | — | progressive rock band |
| Comet Gain | 1992 | — | — |
| Common Gods | June 2012 | — | — |
| Complex | 1968 | — | — |
| Conan | 2006 | — | UK doom |
| Condemned 84 | 1980 | — | — |
| Conflict | 1981 | — | — |
| Congenital Abnormalities | 2015 | — | — |
| Conjurer | 2014 | — | — |
| Conquering Animal Sound | 2008 | — | — |
| Consecration | 2010 | — | — |
| Coprocephalic Mutation | 2017 | — | — |
| Cornershop | 1991 | — | — |
| Corvus | 2007 | — | — |
| Cosmonauts | 2010 | — | — |
| Countless Skies | 2012 | — | — |
| Country Teasers | 1993 | — | — |
| Counts of the Netherworld | 22 April 2008 | — | — |
| Courteeners | 2006 | — | — |
| Coves | 2011 | — | — |
| Cradle of Filth | 1991 | — | — |
| Cranes | 1986 | — | British dream pop band |
| Crash Paris | September 2011 | — | — |
| Craven Idol | 2005 | — | — |
| Crazy Arm | 2005 | — | — |
| Creaming Jesus | 1988 | — | — |
| Credit to the Nation | 1991 | — | — |
| Crimson Tears | 2003 | — | — |
| Crippled Black Phoenix | 2004 | — | UK rock band |
| Crisis | 1977 | — | 1970s British punk band |
| Crispy Ambulance | 1977 | — | — |
| Cristobal and the Sea | 1 September 2012 | — | — |
| Crocodile God | 1992 | — | — |
| Crom Dubh | 2003 | — | — |
| Cronos | 1988 | — | British metal band with Conrad "Cronos" Lant |
| Crowns | 2010 | — | — |
| Cruciamentum | 2005 | — | — |
| Cryptic Shift | 2013 | — | — |
| Cryptworm | 2014 | — | — |
| Crystal Balloon | October 2013 | — | — |
| Crystal Fighters | 2007 | — | — |
| Crywank | 2009 | — | — |
| Cubanate | 1992 | — | British industrial rock / electro-industrial group |
| CUD | 1987 | — | — |
| Cult Maniax | 1978 | — | — |
| Cultural Amnesia | 1979 | — | — |
| Culture Club | 1981 | — | English pop group |
| Current 93 | 1982 | — | — |