| C&V Property Management Limited | Nottingham | 2025 |
| C&Wh Butt Limited | Northampton | 2023 |
| C&Z Deuchar Holdings Ltd | Dartmouth | 2024 |
| C'Estbonne Ltd | London | 2025 |
| C'Mavi Limited | Bolney | 2015 |
| C,S&A Forrest Holdings Limited | Milton Keynes | 2025 |
| C-43 Ltd | Cardiff | 2016 |
| C-Bee Holding Ltd | Hamilton | 2025 |
| C-Bridge Capital (UK) Ltd | London | 2022 |
| C-Five Ventures Ltd | Bury St. Edmunds | 2026 |
| C-H Q Score Holdings Limited | Dorking | 2026 |
| C-Lab Holdings Limited | Norwich | 2021 |
| C-Mart Group Ltd | London | 2014 |
| C-Pro Direct Holdings Limited | London | 2025 |
| C-Quence Holdings Limited | London | 2018 |
| C-Rod Holdings Ltd | Nottingham | 2024 |
| C-Salt Marine Limited | Hampshire | 2006 |
| C-Squared Group Ltd | London | 2025 |
| C-Squared Holding Limited | London | 2020 |
| C-Suite Pension Strategies Ltd | London | 2016 |
| C-Suite Strategies Ltd | London | 2016 |
| C-Talisman Ltd. | Birmingham | 1999 |
| C-Tec Engineering Holdings Ltd | Belfast | 2021 |
| C-Tec Holding Limited | Lytham | 2008 |
| C. & a. Roberts Holdings Limited | London | 2017 |
| C. & G. Computers Limited | Brighouse | 2020 |
| C. & H. (UK) Limited | Ipswich | 2014 |
| C. & P. Group Holdings Limited | Swansea | 2018 |
| C. & S. (Life & Pensions) Limited | Street, Glasgow | 1987 |
| C. & S. Holdings South Wales Limited | Neath | 2020 |
| C. Alexander Financial Planning Limited | Nottingham | 2014 |
| C. B. Motors (Kent) Limited | Ashford | 1982 |
| C. Bancroft Limited | Nottingham | 1987 |
| C. Billor Limited | Southampton | 2024 |
| C. Czarnikow Limited | London, | 1996 |
| C. Dominic Management Group Ltd | Bournemouth | 2025 |
| C. Hoare & Co. | London | 1929 |
| C. J. Upton (Demergeco) Limited | Leicester | 2022 |
| C. J. Upton Investments Limited | Leicester | 2022 |
| C. Lewis (UK) Holding Ltd | London | 2018 |
| C. Lewis (UK) Limited | London | 2005 |
| C. M. Salvago & CIE Ltd | London | 2023 |
| C. Martha Limited | Ayr | 2023 |
| C. Mcdonald Brown Limited | Hull | 1984 |
| C. Toms & SON (Holdings) Limited | Fowey | 2020 |
| C. W. Booth Holdings Limited | Banbury | 1978 |
| C.A. DAW & SON (Insurance Services) Limited | | 2004 |
| C.A. Strawson Holdings Limited | Newark | 2020 |
| C.A. Whitaker Limited | Norwich | 2005 |
| C.A.A.S. Holdings Limited | Inverurie | 2020 |
| C.A.F Group Holdings Limited | London | 2024 |
| C.A.H Contracting Solutions Ltd | Pengam | 2013 |
| C.A.J. Management Ltd | Hoddesdon | 2022 |
| C.A.K Holdings Ltd | London | 2025 |
| C.A.L.M. Group Holdings Limited | Peterborough | 2023 |
| C.A.R.S. Holdings (2022) Limited | London | 2022 |
| C.A.R.S. UK Holdings Limited | Maldon | 2015 |
| C.A.S.C. Holdings Ltd | Wigan | 2019 |
| C.B. Buildings and Claims Limited | Loughton | 2013 |
| C.B. Hughes Limited | Portsmouth | 1998 |
| C.C Marine Group Limited | Reigate | 2025 |
| C.C. Flint and Company Limited | London | 1982 |
| C.C. Insurance Services Ltd. | Stoke On Trent | 1989 |
| C.C. Licensing | | 1988 |
| C.C.S. Financial Services Limited | Woking | 1991 |
| C.C.S. Insurance Services Limited | Woking | 1986 |
| C.Chalmer Holding Ltd | London | 2020 |
| C.Chasney Limited | Romford | 1955 |
| C.E Capital Holdings Ltd | Chadwell Heath | 2024 |
| C.E.L. Group Limited | Chippenham | 1981 |
| C.E.N Ventures Limited | Bournemouth | 2026 |
| C.F. Capital Holdings Limited | Bishops Stortford | 2019 |
| C.F. Capital PLC | Bishops Stortford | 1988 |
| C.F. Roberts (Holdings) Limited | Hereford | 1995 |
| C.F. Smith Wealth Management Ltd. | Maidstone | 2017 |
| C.F.G. Emerald Consulting Limited | Ipswich | 2022 |
| C.G. Holdings East Anglia Ltd | Norwich | 2015 |
| C.G. Turnbull Holdings Limited | Lytham St. Annes | 2012 |
| C.G.Y. Holdings Limited | Newton Abbot | 2023 |
| C.H.O.O.K.S Ltd | Rochdale | 2024 |
| C.Habert International Ltd | London | 2026 |
| C.Hemmings & Co. Limited | Liverpool | 1958 |
| C.I. Claims Ltd | Hoddesdon | 2011 |
| C.I.B. (Life & Pensions) Limited | Gateshead | 1987 |
| C.I.Electronics Limited | Salisbury | 2024 |
| C.I.L Hope Holdings Ltd | Epsom | 2025 |
| C.I.R. Holdings Limited | London | 2022 |
| C.I.S. (Cardiff) Limited | Cardiff | 2014 |
| C.J. Coleman & Company Limited | London | 1973 |
| C.J. Coleman Holdings Limited | London | 1976 |
| C.J. Leonard & Sons (Holdings) Limited | Guisborough | 2025 |
| C.J. Lynch Holdings Limited | Minehead | 2002 |
| C.J. Rhodes Investments Limited | Alfreton | 2024 |
| C.J.Z Sceattas Holdings Ltd | London | 2025 |
| C.K. Contracts (Holdings) 2019 Limited | Renfrewshire | 2019 |
| C.L. Flooring Solutions EOT Trustee Limited | Glasgow | 2024 |
| C.L.C.A Holdings Limited | Shrewsbury | 2017 |
| C.L.Schofield Group Ltd | Leeds | 2024 |
| C.M. London Property Limited | London | 2025 |
| C.M. One House Ltd | London | 2019 |