| Clarity Financial Training Ltd | Potters Bar | 2018 |
| Clarity Financial Wellbeing Ltd | Altrincham | 2026 |
| Clarity Fire and Safety Training Limited | Bury | 2017 |
| Clarity Matters Ltd | Kington | 2024 |
| Clarity Path Dyslexia Limited | Bootle | 2026 |
| Clarity Personalised Solutions Ltd | Sheffield | 2018 |
| Clarity SEN Consultancy Limited | Chelmsford | 2018 |
| Clarity Training and Recruitment Ltd | Liverpool | 2025 |
| Clarity Training Ltd | Birmingham | 2025 |
| Clarity Translation & Interpreting Limited | Leeds | 2025 |
| Clarivox Limited | Edinburgh | 2024 |
| Clarke & Co Hockey Limited | Nottingham | 2018 |
| Clarke CKD Limited | Sunbury-On-Thames | 2023 |
| Clarke Coaching Ltd | Perth | 2021 |
| Clarke Consultancy and Psychology Services Ltd | Maidstone | 2025 |
| Clarke Education Services Ltd | Bromsgrove | 2025 |
| Clarke Hall Clinics Limited | Wakefield | 2021 |
| Clarke Training (NI) Limited | Newry | 2014 |
| Clarkehouse Education Consultancy Limited | Sheffield | 2025 |
| Clarkes Training Solutions Ltd | Northwich | 2022 |
| Clarkmorgan Limited | London | 2020 |
| Clarks Rail Training Ltd | Doncaster | 2021 |
| Clarkson Evans Training Limited | Gloucester | 2008 |
| Clarkston ND Ltd | Edinburgh | 2026 |
| Clarus Academy Ltd | Lincoln | 2026 |
| Claryence Limited | Budleigh Salterton | 2025 |
| Clas Education Consultancy Limited | Hinckley | 2024 |
| Class 1 Driving School Ltd | Swindon | 2013 |
| Class ACT (GB) Limited | Oxted | 2003 |
| Class ACT Tutoring Ltd | Neath | 2024 |
| Class Catch Limited | Bury | 2025 |
| Class Clever Limited | London | 2017 |
| Class Clowns Ltd | Royston | 2025 |
| Class Divide Limited | Brighton | 2024 |
| Class Leading Limited | Darlington | 2012 |
| Class Martial Arts Ltd | Shrewsbury | 2020 |
| Class Measures Limited | Sheffield | 2006 |
| Class Muse Training Ltd | Canvey Island | 2026 |
| Class Norfolk Limited | Norwich | 2019 |
| Class of London Teaching Ltd | Poole | 2019 |
| Class of Your Own Limited | Clitheroe | 2009 |
| Class on Call Ltd | London | 2026 |
| Class Rheum Limited | London | 2024 |
| Class Roots Consultancy Ltd | Stoke-On-Trent | 2019 |
| Class Talent Ltd | Northampton | 2013 |
| Class Topper UK Ltd | Newport | 2023 |
| Class Training (NW) Ltd | Wirral | 2023 |
| Class Training Ltd | Wirral | 2018 |
| Classace Ltd | London | 2025 |
| Classbro Ltd | Beckenham | 2021 |
| Classcompass Ltd | London | 2025 |
| Classes Abroad Limited | Chippenham | 2009 |
| Classforge Ltd | London | 2025 |
| Classic Education Private Limited | Barnet | 2019 |
| Classic IS Key Ltd | Redhill | 2023 |
| Classic Music Solutions Limited | Ashton Under Lyne | 2013 |
| Classical Concerts Productions Ltd | | 2008 |
| Classical Conversations Uk&I Limited | Tonbridge | 2020 |
| Classical Fine Arts Academy Ltd | Arkley | 2026 |
| Classical Liberal Arts UK Limited | Clitheroe | 2026 |
| Classical Pilates Academy Limited | Sutton Coldfield | 2023 |
| Classical Voice Training Limited | St. Helens | 2015 |
| Classics Agenda Limited | Luton | 2013 |
| Classics for ALL | London | 2010 |
| Classicus International Limited | Steeple Aston | 2022 |
| Classix Recordings Limited | Altrincham | 2003 |
| Classly Ltd | Caerphilly | 2023 |
| Classoos UK Limited | London | 2017 |
| Classroom Catalyst Ltd | London | 2025 |
| Classroom Companion Ltd | Poole | 2025 |
| Classroom Computing Ltd | York | 2021 |
| Classroom Education Services Ltd | London | 2017 |
| Classroom Pulse Limited | London | 2026 |
| Classroom Secrets Limited | Halifax | 2013 |
| Classtasker UK Ltd | Farnborough | 2025 |
| Classtutor Services Ltd | Slough | 2024 |
| Clavelshay Hats Limited | Bromley | 2023 |
| Claverdon Village Nursery Limited | Redditch | 2001 |
| Clavering & Arkesden Preschool | Saffron Walden | 2009 |
| Clavian Ltd | Colchester | 2021 |
| Claviermo Limited | London | 2026 |
| Clavis Aditum Limited | Purley | 2015 |
| Clay & Dough Ltd | London | 2025 |
| Clay Club London Ltd | London | 2025 |
| Clay Creators Derby Limited | Nottingham | 2021 |
| Clay Creators Limited | Nottingham | 2016 |
| Clay Creators Loughborough Limited | Nottingham | 2024 |
| Clay Creators Manchester Limited | Nottingham | 2025 |
| Clay Target Events Ltd | Derby | 2016 |
| Clay Time Pottery Place C.I.C. | London | 2016 |
| Clay Trap Ltd | Helston | 2023 |
| Clay Works Studios CIC | Thornhill | 2022 |
| Clay Yorkshire Limited | West Bretton | 2022 |
| Claycross Bricklaying Academy Ltd | Chesterfield | 2021 |
| Claydon Hawke Limited | Royston | 2012 |
| Clayesmore School | Blandford | 1940 |
| Clayfolk Studios Ltd | Deal | 2025 |
| Claylands Private Nursery Limited | South Queensferry | 2002 |
| Claymore Training Ltd | Airdrie | 2015 |
| Clays Lane Advice and Training Centre | London | 2007 |