| Concept 4 Football Limited | Sidcup | 2024 |
| Concept Art Ltd | London | 2010 |
| Concept Audio Limited | Brighton | 2005 |
| Concept Creative Consultants Limited | Lancing | 2000 |
| Concept Entertainment Group Ltd | Bath | 2018 |
| Concept Event Solutions Ltd | Bedford | 2019 |
| Concept Events & Promotions Limited | Shipston-On-Stour | 2019 |
| Concept Events SW Limited | Newton Abbot | 2022 |
| Concept Fitness & Recovery Ltd | Doncaster | 2026 |
| Concept Fitness Essex Limited | Essex | 2007 |
| Concept Hospitality Services Ltd | Northallerton | 2009 |
| Concept Polo Ltd | Alton | 2023 |
| Concept Properties Loudwater Ltd | High Wycombe | 2016 |
| Concept Studios (MCR) Ltd | Warrington | 2025 |
| Concept Swimming Ltd | London | 2015 |
| Concept Targets Limited | Hook | 2007 |
| Concept UK Clubs Limited | Ringwood | 2015 |
| Concert & Corporate Crew Ltd. | Shoreham-By-Sea | 2004 |
| Concert Artist Promotions Ltd | London | 2021 |
| Concert Breaks Limited | London | 1999 |
| Concert by the Castle Limited | Chalfont St. Giles | 2023 |
| Concert Events Global Ltd | London | 2024 |
| Concert Piano Services Ltd | Ruislip | 2025 |
| Concert Production Services Limited | Christchurch | 1998 |
| Concert Stuff UK Limited | Liverpool | 2026 |
| Concert Theatre Works Ltd | Faversham | 2020 |
| Concerto Caledonia | Glasgow | 1999 |
| Concerts for Good Causes Ltd | Newport | 2024 |
| Concerts in the West | Taunton | 2010 |
| Conch Studios UK Limited | London | 2018 |
| Concord District Youth CIC | Washington | 2026 |
| Concord Music Limited | 535 Kings Road | 1962 |
| Concord Simp Ltd. | London | 2007 |
| Concorde on the Thames Ltd | Walton On Thames | 2023 |
| Concorde Sports Ltd | Northampton | 2025 |
| Concrete Candy Ltd | Bromley | 2009 |
| Concrete Jungle Yoga Ltd | London | 2019 |
| Concrete KIN Limited | Bromley | 2019 |
| Concrete Mango Ltd | Runcorn | 2020 |
| Concrete Roses London Collective Limited | Shenstone | 2026 |
| Concrete Roses Studios Ltd | Southsea | 2025 |
| Concrete Surf Ltd | Loanhead | 2026 |
| Concrete Waves London C.I.C. | London | 2023 |
| Condiment Claire Limited | London | 2026 |
| Condition Code Ltd | Derby | 2023 |
| Condo Group Ltd | London | 2023 |
| Condor Club Limited | Holywood | 2026 |
| Condor Clubhouse Limited | Whitstable | 2026 |
| Condor Motorsports Club Limited | Lochgelly | 2018 |
| Condor Sports Limited | London | 2014 |
| Conduit Sound Ltd | Liverpool | 2024 |
| Conecraft Limited | West Midlands | 1988 |
| Confederation of Professional Golf Limited | Tamworth | 1992 |
| Conference Craft Limited | Surbiton | 1982 |
| Conference Equipment Services Limited | Pontefract | 2018 |
| Confessions of a Traitor Ltd | Sutton | 2021 |
| Confessions Tattoo Studio Ltd | Walsall | 2025 |
| Confetti Entertainment Ltd | Bexhill-On-Sea | 2020 |
| Confetti Magic Limited | St. Albans | 2000 |
| Confidance Limited | Folkestone | 2020 |
| Confidanceuk Ltd | Chichester | 2025 |
| Confidence Club Coaching Ltd | Liverpool | 2021 |
| Confidence Club Ltd | Wigan | 2022 |
| Confidence for Kids CIC | Wigan | 2026 |
| Confident Games Limited | London | 2018 |
| Confident Theatre Company Ltd | Leigh-On-Sea | 2026 |
| Conflict Resolution Larp Ltd | Edinburgh | 2012 |
| Conflux Entertainment Ltd | Glasgow | 2025 |
| Conflux Scotland Ltd. | Glasgow | 2011 |
| Confused Youth Audio Limited | London | 2006 |
| Confuzzled UK Ltd | London | 2007 |
| Congellous Ltd | Hove | 2018 |
| Congleton & MEAD0W Vale F00TBALL Club Limited | Congleton | 1980 |
| Congleton Building Preservation Trust | Cheshire | 2001 |
| Congleton Community Project Limited | Congleton | 1994 |
| Congleton Golf Club Limited | Congleton | 1920 |
| Congleton Lawn Tennis Club Limited | Stoke-On-Trent | 1927 |
| Congleton Live Community Interest Company | Congleton | 2020 |
| Congleton Museum Trust | Congleton | 1988 |
| Congleton Town FC (Operations) Limited | Congleton | 2023 |
| Congleton Town Limited | Congleton | 1994 |
| Congo Design Limited | Blackpool | 2013 |
| Congolese Dance Tutorials Ltd | Dagenham | 2025 |
| Congoman Limited | London | 2021 |
| Congratulations Limited | Hove | 2024 |
| Congregate Works CIC | Margate | 2026 |
| Congresbury Sports and Recreation Club Limited | Bristol | 2023 |
| Congress Theatre Company | Cwmbran | 2009 |
| Coni Lighting Limited | Leeds | 2010 |
| Conifer Comedy Limited | Hitchin | 2015 |
| Conifer Records Limited | London | 1986 |
| Conifercourt Leisure Limited | Epsom | 1985 |
| Conisbrough Community Association Limited | Doncaster | 1997 |
| Conisbrough Community Library Limited | Doncaster | 2014 |
| Conjugate Sports Performance Ltd | Liverpool | 2023 |
| Conjureman Productions Limited | London | 2024 |
| Conker Enterprises Limited | Ware | 2023 |
| Conlan Boxing Ltd | Belfast | 2018 |
| Conlan Boxing Management Limited | Belfast | 2025 |
| Conlan Sports Ltd | Belfast | 2021 |