| Cayenne Copper Limited | London | 2024 |
| CB OIL & GAS Limited | Manchester | 2012 |
| CB OIL Services Ltd | Ashton-Under-Lyne | 2023 |
| Cb&I Asset Solutions Parent Company Limited | London | 2025 |
| CC Inspection Ltd | Aberdeen | 2016 |
| CCD East Coast Ltd | Dundee | 2022 |
| CCF Catering Ltd | Bedford | 2023 |
| Ccle Fabrication Ltd | Isle Of Lewis | 2017 |
| CCP Aggregates Limited | Wrexham | 1955 |
| CD Processing Ltd | London | 2017 |
| CDP Plant Limited | Chesterfield | 1991 |
| Cdri Limited | Westhill | 2024 |
| Ceanic Ltd | Great Yarmouth | 2012 |
| Ceased Trading 12208392 Ltd | Cardiff | 2019 |
| CEK & Group Limited | Grays | 2024 |
| Celera Support Services Limited | Aberdeen | 2011 |
| Celmaris Resources Ltd | London | 2025 |
| Celtic Drilling Limited | Newquay | 2017 |
| Celtic Energy Limited | Cardiff | 1994 |
| Celtic Mining Group Limited | Cardiff | 2004 |
| Celtic Mining Limited | Cardiff | 1994 |
| Celtic Quarries Limited | Youlgrave | 2023 |
| Celtic Resources (Central Asia) Limited | London | 1999 |
| Cemcor Ltd | Shrewsbury | 2015 |
| Cemex UK Marine Limited | Coventry | 1911 |
| Cemex UK Materials Limited | Coventry | 2003 |
| Cemex UK Operations Limited | Coventry | 1960 |
| Cemore Consultants Ltd | London | 2024 |
| Cenako Limited | Maghera | 2020 |
| Cenovus Investments Limited | Ruislip, | 2021 |
| Centaurus Royalties Limited | London | 2004 |
| Centenary Mining Limited | East Grinstead | 2026 |
| Central Anatolian Resources Limited | Brentwood | 2017 |
| Central Asia Investments Ltd | Maidstone | 2022 |
| Central Construction Services Limited | Coalville | 1997 |
| Central Copper Resources Limited | London | 2021 |
| Central Recycling Yorkshire Ltd | Doncaster | 2018 |
| Central Ropes Limited | Dundee | 2011 |
| Central Screen & Crushing Services Limited | Ashby-De-La-Zouch | 2002 |
| Centreline Technical Services Limited | Wallasey | 2014 |
| Centrica Energy Storage Limited | Hessle | 1996 |
| Centrica LNG Company Limited | Berkshire | 2007 |
| Centrica LNG UK Limited | Windsor | 2015 |
| Centrica Offshore Investments Limited | Hessle | 2024 |
| Centrica Offshore UK Limited | Hessle | 2001 |
| Centurion Mining Limited | London | 2013 |
| Centurion Subsea Services Limited | Aberdeen | 2004 |
| Centurion Universal Limited | London | 2011 |
| Ceramec Ltd | London | 2009 |
| Ceraphi Energy Ltd | Great Yarmouth | 2013 |
| Ceraphi Energy Ventures Ltd | Great Yarmouth | 2012 |
| Ceraphi Ltd | Great Yarmouth | 2020 |
| Cerberus Inspection Ltd | Exeter | 2026 |
| Cerkines Limited | London | 2026 |
| CES Quarry Products Limited | Ballynahinch | 1962 |
| Cetco Energy Services Limited | London | 2010 |
| CFI Services Limited | London | 2012 |
| CG Craig Ltd | Paisley | 2015 |
| CG Offshore Ltd | Wymondham | 2025 |
| CGM Piping Ltd | Fochabers | 2015 |
| CGR Safety Solutions Limited | Middlesbrough | 2017 |
| CGT Access Ltd | Lytham St Annes | 2019 |
| CGW Enterprises Limited | Aberdeen | 2017 |
| CH Pipework Ltd | Dunfermline | 2022 |
| CH9 Engineering Management Services Ltd | Falkirk | 2019 |
| Chaarat Gold Services Limited | Eastleigh | 2018 |
| Chadwich Lane Quarry Limited | Bromsgrove | 1999 |
| Challenge Products Ltd | Aberdeen | 2008 |
| Chamosite Limited | Banchory | 2024 |
| Champion Contract Services (North East) Limited | Saltburn-By-The-Sea | 2017 |
| Champion GAS Ltd | London | 2021 |
| Chandler Equity Limited | Sutton Coldfield | 2020 |
| Change Energy Limited | Aberdeen | 2010 |
| Changeover Technologies Limited | Belfast | 2009 |
| Chantry Sand Quarry Holdings Limited | Brighton | 2015 |
| Chantry Sand Quarry Limited | Brighton | 2015 |
| Chap Quarries (Aberdeen) Limited | Westhill | 1980 |
| Chapman Consultancy Ltd | London | 2019 |
| Chapman Drilling Ltd | Truro | 2019 |
| Chariot Offshore GAS Limited | London | 2023 |
| Charles Multipro Solutions Ltd | Birmingham | 2024 |
| Chartmount Minerals Limited | Edinburgh | 1997 |
| Chartrange (Quarry Products) Limited | Cheshire | 1996 |
| Cheam Leaded Lights Limited | London | 2006 |
| Cheiron Energy Limited | Altrincham | 2010 |
| Cheiron OIL & GAS Limited | Altrincham | 2021 |
| Cheiron S ABU Sennan Limited | Altrincham | 2021 |
| Cheiron SE Horus Limited | Altrincham | 2021 |
| Cheiron W EL Fayum Limited | Altrincham | 2021 |
| Cheiron WD Exploration Limited | Altrincham | 2021 |
| Chell (Memsie) Limited | Fraserburgh | 2013 |
| Chell's Engineering Limited | Stoke-On-Trent | 2020 |
| Cheranna Energy Limited | Aberdeen | 2018 |
| Cheshire and North Wales Sand and Gravel Limited | Telford | 2017 |
| Cheshire Blocks Limited | Stockport | 2022 |
| Chesilton Consultancy Limited | London | 2008 |
| Chess Subsea Engineering Europe Ltd | London | 2016 |
| Chevalier Engineering Ltd. | Belhelvie | 2011 |
| Cheverton Aggregates Ltd | Alresford | 2005 |
| Chevron Britain Limited | London | 1971 |