| Colours Healthcare Ltd | Wholesale & retail | 2023 |
| Colours of Design Ltd | Wholesale & retail | 2008 |
| Coltish Events & Media Ltd | Information & communication | 2019 |
| Colton Health Hub Limited | Health & social care | 2024 |
| Columbo Jazz Limited | Hospitality | 2015 |
| Columbo Music Limited | Arts & recreation | 2023 |
| Columbo Property Limited | Real estate | 2022 |
| Columbo South Limited | Hospitality | 2015 |
| Colux Recruitment Limited | Information & communication | 2016 |
| Colway Fabrications Ltd | Manufacturing | 2022 |
| Colway Security UK Ltd | Manufacturing | 2011 |
| Colwick Cars Ltd | Transport & logistics | 2012 |
| Colwin Construction Limited | Construction | 1994 |
| Comac Site Services Limited | Professional & scientific | 1986 |
| Comasu Investments Ltd | Real estate | 2025 |
| Combatek Limited | Information & communication | 2013 |
| Comber House Ltd | Professional & scientific | 2022 |
| Combimate Limited | Extraterritorial | 2009 |
| Combinatrics Communications Limited | Information & communication | 2018 |
| Combine Performance Limited | Other services | 2019 |
| Combined FM Services Group Limited | Administrative & support | 2016 |
| Combined Selection Group (Dubai) Ltd | Administrative & support | 2006 |
| Combined Selection Group Holdings Ltd | Administrative & support | 2015 |
| Combined Selection Group Ltd | Professional & scientific | 2009 |
| Combined Space Technologies Limited | Administrative & support | 2025 |
| Combined Space Technology Limited | Administrative & support | 2025 |
| Combo Xpress Limited | Hospitality | 2024 |
| Comcat Limited | Construction | 2015 |
| Come Outside CIC | Arts & recreation | 2024 |
| Come Play Records Ltd | Information & communication | 2022 |
| Come Play With ME CIC | Information & communication | 2015 |
| Comedy Ticket Limited | Arts & recreation | 2022 |
| Comer (UK) Ltd | Manufacturing | 1995 |
| Cometlodge Limited | Households | 1987 |
| Comfi Plus Limited | Wholesale & retail | 2013 |
| Comfizz Limited | Extraterritorial | 2013 |
| Comfort Forever Limited | Other services | 2025 |
| Comfort Haven Care Ltd | Health & social care | 2026 |
| Comfort Home Lets Ltd | Real estate | 2018 |
| Comforting Healthcare Ltd | Health & social care | 2017 |
| Comhar Capital (1801) Limited | Professional & scientific | 2018 |
| Comhar Capital (1805) Limited | Administrative & support | 2020 |
| Comhar Capital (1806) Limited | Administrative & support | 2021 |
| Comhar Capital Limited | Financial services | 2017 |
| Comlek Limited | Information & communication | 2015 |
| Comlek Residential Limited | Real estate | 2024 |
| Commence Auction Services Limited | Professional & scientific | 2009 |
| Commence Data Services Limited | Professional & scientific | 2009 |
| Commence Marketing Limited | Administrative & support | 1999 |
| Commerce Intelligence Limited | Wholesale & retail | 2010 |
| Commerce Park One Limited | Construction | 2006 |
| Commercial Blinds Direct Ltd | Manufacturing | 2025 |
| Commercial Dynamics Limited | Construction | 2004 |
| Commercial Fire P.S Limited | Construction | 2012 |
| Commercial GAS Works Ltd | Construction | 2025 |
| Commercial Grid Ltd | Real estate | 2025 |
| Commercial Kitchens & Laundry Limited | Professional & scientific | 2022 |
| Commercial Lines Limited | Manufacturing | 1983 |
| Commercial Network SAL Limited | Wholesale & retail | 2025 |
| Commercial Parts Solutions Ltd | Wholesale & retail | 2020 |
| Commercial Performance Improvement Ltd | Professional & scientific | 2011 |
| Commercial Property Brokers Limited | Other services | 2013 |
| Commercial Property Refurb Limited | Construction | 2011 |
| Commercial Security Limited | Administrative & support | 2025 |
| Commercial Services Design Holdings Limited | Construction | 2015 |
| Commercial Services Design Limited | Construction | 2012 |
| Commercial Signage Solutions Limited | Manufacturing | 2015 |
| Commercial Space (Yorkshire) Ltd | Real estate | 2012 |
| Commercial Systems International Limited | Manufacturing | 1986 |
| Commercial Transport 22 Limited | Wholesale & retail | 2020 |
| Commercial UK Cleaning Ltd | Administrative & support | 2025 |
| Commercial Waste Ltd | Extraterritorial | 2021 |
| Commercialblindsuk Limited | Construction | 2008 |
| Commerson Estate Management Limited | Construction | 2010 |
| Committed Quality Service Ltd | Construction | 2024 |
| Common Hill Limited | Construction | 2022 |
| Common Room North Ltd | Health & social care | 2019 |
| Commonside Traders Ltd | Wholesale & retail | 2020 |
| Commotion Clothing Limited | Extraterritorial | 2025 |
| Comms 2 Cloud Ltd | Construction | 2022 |
| COMMS2BIZZ Ltd | Information & communication | 2013 |
| Commstruct Construction Management Ltd | Construction | 2026 |
| Commstruct Ltd | Construction | 2024 |
| Commun IQ Invest Ltd | Financial services | 2015 |
| Communication Master Ltd | Wholesale & retail | 2024 |
| Communication Stem Limited | Information & communication | 1996 |
| Communication Worx Limited | Professional & scientific | 2014 |
| Communique (Property Developments) Limited | Construction | 1993 |
| Communisis Trustee (2011) Company Limited | Professional & scientific | 2011 |
| Communitas Energy CIC | Information & communication | 2016 |
| Communitea Wellness CIC | Health & social care | 2025 |
| Communities to Bridge CIC | Public administration | 2026 |
| Community Alliance Housing C.I.C. | Hospitality | 2022 |
| Community Ambition CIC | Administrative & support | 2024 |
| Community Care & Rehabilitation Ltd | Health & social care | 2026 |
| Community Development Services Alliance Limited | Professional & scientific | 2009 |
| Community Einstein Ltd | Professional & scientific | 2022 |
| Community Environmental Learning and Impact Alliance CIC | Information & communication | 2025 |
| Community Foundation for Leeds | Administrative & support | 2002 |
| Community Health South Elmsall Limited | Financial services | 2024 |