| Claretha LP | | 2016 |
| Clarewight Industries LP | | 2013 |
| Clarify Clutter Ltd | Administrative & support | 2024 |
| Clarinet Communications Limited | Information & communication | 2015 |
| Clarinet Properties Ltd | Real estate | 2016 |
| Claring Capital Ltd | Professional & scientific | 2023 |
| Claris Consulting LP | | 2015 |
| Claris Sales LP | | 2015 |
| Clarisar Limited | Health & social care | 2020 |
| Clarity Check Ltd | Professional & scientific | 2025 |
| Clarity Coffee Co. Limited | Wholesale & retail | 2023 |
| Clarity I.T. & VPN Solutions Limited | Information & communication | 2017 |
| Clarity Independent Financial Advisers Limited | Other services | 2006 |
| Clarity Independent Wealth Management Limited | Financial services | 2019 |
| Clarity Marketing (UK) Limited | Professional & scientific | 2013 |
| Claritybuilds Holding LP | | 2025 |
| Clarivate IP Services Limited | Professional & scientific | 2008 |
| Clarivox Limited | Education | 2024 |
| Clariweek Ltd | Information & communication | 2025 |
| Clark Alliance LP | | 2017 |
| Clark Business Development Limited | Information & communication | 2014 |
| Clark Investments Limited | Real estate | 2005 |
| Clark Property Group Limited | Real estate | 2024 |
| Clark Surgery Limited | Health & social care | 2013 |
| Clark Technical Consultancy Limited | Professional & scientific | 2025 |
| Clarkridge Properties Ltd | Real estate | 2026 |
| Clarkson Assets LP | | 2013 |
| Clarkson Auto Services Ltd | Wholesale & retail | 2023 |
| Clarkson Business LP | | 2016 |
| Clarkson Guthrie Limited | Other services | 2010 |
| Clarkston Greig LLP | | 2007 |
| Clarkston Holdings Limited | Professional & scientific | 2007 |
| Clarkston Limited | Real estate | 1997 |
| Clarkston ND Ltd | Education | 2026 |
| Claroom Chain System Limited | Information & communication | 2026 |
| Clary Allan Limited | Professional & scientific | 2021 |
| Clary Way LP | | 2016 |
| Clash Gour Windfarm Holdings Limited | Energy | 2018 |
| Clashindarroch II Wind Farm Limited | Energy | 2024 |
| Class 1 Products Limited | Hospitality | 2021 |
| Class 98 Limited | Construction | 1998 |
| Class Apartments Ltd | Real estate | 2023 |
| Class C Quotaholder (Prumo) GP, LLP | | 2018 |
| Class C Quotaholder (Prumo), L.P. | | 2018 |
| Class Energy Trade LP | | 2015 |
| Class Promotions L.P. | | 2012 |
| Classic Agency L.P. | | 2011 |
| Classic Business LP | | 2016 |
| Classic Business Services L.P. | | 2009 |
| Classic Lagoon LP | | 2016 |
| Classic Lodges Limited | Hospitality | 1992 |
| Classic Partnership L.P. | | 2011 |
| Classic Promotions LP | | 2011 |
| Classic Property Limited | Real estate | 2017 |
| Classic Supplies L.P. | | 2012 |
| Classic Support Services L.P. | | 2012 |
| Classic Supreme LP | | 2016 |
| Classy Elite LP | | 2016 |
| Clatworthy SLP | | 1997 |
| Claudia Cranford Limited Partnership | | 2022 |
| Claudia Soare Packaging Consulting LP | | 2025 |
| Clauz Trade LP | | 2015 |
| Claws and Pause Ltd | Other services | 2024 |
| Claxson Services & Management LP | | 2012 |
| Claxton Elite LP | | 2015 |
| Clay Hutchinson LP | | 2018 |
| Claycrest Limited | Professional & scientific | 2003 |
| Clayfords Energy Storage Limited | Professional & scientific | 2018 |
| Clayhill Inventions L.P. | | 2012 |
| Claylake Limited | Information & communication | 2001 |
| Claymore Elevator Company Limited | Construction | 2009 |
| Claymore Games Ltd | Wholesale & retail | 2025 |
| Claymore House L.P. | | 2009 |
| Claymore Merchant & Finance Associates | | 1993 |
| Claymore Planning and Development Limited | Other services | 2024 |
| Claymore Racing Ltd | Agriculture & fishing | 2023 |
| Clays Farm Solar Limited | Energy | 2021 |
| Clayston Holdings LP | | 2015 |
| Claysyke Ltd | Construction | 2022 |
| Claytara Limited | Arts & recreation | 1995 |
| Clayton Care Limited | Health & social care | 2010 |
| Clayton Lighting & Traffic Ltd. | Other services | 2017 |
| Claytonhill Alliance LP | | 2013 |
| CLB Construction & Roofing Solutions Ltd | Construction | 2025 |
| Clcm Auto Services Ltd | Wholesale & retail | 1989 |
| Clean About Town Ltd | Administrative & support | 2024 |
| Clean Air Energy Ltd | Construction | 2021 |
| Clean Digital Limited | Professional & scientific | 2012 |
| Clean Digital Trustees Limited | Administrative & support | 2023 |
| Clean Energy CI Feeder LP | | 2010 |
| Clean Energy Fund CI LP | | 2009 |
| Clean Genie Group Ltd | Administrative & support | 2015 |
| Clean Girl Aesthetics Limited | Other services | 2023 |
| Clean Growth Investment Carried Interest LP | | 2020 |
| Clean Happy Ltd | Administrative & support | 2020 |
| Clean House Services Edinburgh Ltd | Administrative & support | 2019 |
| Clean Search Limited | Information & communication | 2025 |
| Clean Stayin Ltd | Administrative & support | 2025 |
| Clean Water Wave C.I.C. | Water & waste | 2017 |
| Clean World Limited | Administrative & support | 2018 |