| Creando Holding Limited | Financial services | 2025 |
| Creatingintelligentfootballers Ltd | Arts & recreation | 2023 |
| Creative Community Events CIC | Arts & recreation | 2024 |
| Creative Noise Communications Limited | Professional & scientific | 2008 |
| Creative Solutions Network LP | | 2014 |
| Creative Solutions Network Ltd | Professional & scientific | 2014 |
| Creative Stuff Ltd | Information & communication | 2024 |
| Creativedigitalsolutions Limited | Professional & scientific | 2024 |
| Creatorverse Ltd | Professional & scientific | 2026 |
| Credencex Limited | Information & communication | 2026 |
| Crest Cafe London Ltd | Hospitality | 2025 |
| Crestway Holdings Limited | Professional & scientific | 2022 |
| Crews Hill CLUB(1920),LIMITED(THE) | Arts & recreation | 1920 |
| Crews Hill Golf Club 2016 Limited | Arts & recreation | 2016 |
| Crews Hill the Little Cafe Ltd | Hospitality | 2022 |
| Crezt Medical Group Ltd | Health & social care | 2023 |
| Crib Tech Limited | Information & communication | 2023 |
| Cricklewood CC Limited | Wholesale & retail | 2015 |
| Cricklewood Developments Limited | Construction | 2014 |
| Crimsol Limited | Real estate | 1998 |
| Crimson Door Ltd | Information & communication | 2011 |
| Crispy Chicken Kebab and Burger Ltd | Hospitality | 2025 |
| Crist DE Services Limited | Other services | 2020 |
| Cristal Cleaning Solution Ltd | Administrative & support | 2023 |
| Cristal Services Ltd | Water & waste | 2024 |
| Criticare Healthcare Professionals Limited | Health & social care | 2013 |
| Critteressentials Ltd | Wholesale & retail | 2026 |
| CRM Marketeers Ltd | Information & communication | 2023 |
| Crosby Electrical Services Limited | Construction | 1986 |
| Crossfield Management Company Limited | Extraterritorial | 1983 |
| Crosslinx Limited | Hospitality | 2012 |
| Crouch END Ltd | Real estate | 2019 |
| Crouch Physio Limited | Other services | 2023 |
| Crowborough Catering Ltd | Hospitality | 2019 |
| Crown Confidential Waste Destruction Limited | Extraterritorial | 2006 |
| Crown Fine Art Limited | Transport & logistics | 2003 |
| Crown Mason Holdings Limited | Real estate | 2024 |
| Crown Postal Services Ltd | Transport & logistics | 2022 |
| Crown Street Takeaway Ltd | Hospitality | 2024 |
| Crown Water Heating Ltd | Wholesale & retail | 2023 |
| Crown Workspace Limited | Transport & logistics | 1996 |
| Crown Worldwide Properties (UK) Limited | Real estate | 1987 |
| Crownandco Ltd | Wholesale & retail | 2024 |
| Crownhill Garden Furniture Ltd | Manufacturing | 2006 |
| Crucible Global Pathways Ltd | Professional & scientific | 2026 |
| Crussh Retail (Fulham Road) Limited | Real estate | 2024 |
| Crussh Retail (High Street Kensington) Limited | Real estate | 2023 |
| Crussh Retail Curzon Limited | Real estate | 2023 |
| Crust and Wine Limited | Hospitality | 2023 |
| Cruz DE LA Cruz Property Ltd | Real estate | 2025 |
| Cryo Medical Logistics Ltd | Transport & logistics | 2024 |
| Crystal Accountants Ltd | Professional & scientific | 2022 |
| Crystal Integrated Security Systems Ltd | Administrative & support | 2020 |
| Crystal Key Properties Ltd | Real estate | 2021 |
| Crystal Light Chandelier Services Limited | Administrative & support | 2023 |
| Crystal Nail Beauty Nottingham Limited | Other services | 2020 |
| Crystal Oaks Commercial Ltd | Wholesale & retail | 2024 |
| Crystal Spritz Cocktails Ltd | Hospitality | 2021 |
| Crystal Tone Studios Ltd | Health & social care | 2025 |
| Crystals With Love Ltd | Manufacturing | 2021 |
| CS Mobil Elderly Care Services Ltd | Health & social care | 2020 |
| CS Platt Ltd | Wholesale & retail | 2025 |
| Csan Ltd | Hospitality | 2020 |
| CT Project Management & Consulting Ltd | Wholesale & retail | 2021 |
| CT4 Investments Ltd | Real estate | 2022 |
| Ctal Ltd | Real estate | 2024 |
| Ctec AI Ltd | Information & communication | 2025 |
| CTL Health and Beauty Ltd | Other services | 2022 |
| Ctlhr Ltd | Professional & scientific | 2016 |
| CTO Properties Limited | Real estate | 2023 |
| Cube Architects Ltd | Professional & scientific | 2012 |
| Cubeandblack Ltd | Professional & scientific | 2015 |
| Cubed Creative Limited | Administrative & support | 2004 |
| Cubic Fire & Security Ltd | Administrative & support | 2022 |
| CUC & CON Ltd | Other services | 2019 |
| Cucumber Films Limited | Information & communication | 2021 |
| Cuddle Tots Nursery Limited | Health & social care | 2022 |
| CUE Transport Company 0503 Ltd | Transport & logistics | 2025 |
| Cuffley Investments Limited | Real estate | 2010 |
| Culford DE Beauvoir Ltd | Financial services | 2012 |
| Culturavault CIC | Arts & recreation | 2025 |
| Cupcakesbytiffani Ltd | Wholesale & retail | 2023 |
| Cupex Limited | Health & social care | 2022 |
| Cupids Green Limited | Professional & scientific | 2017 |
| Cura International PVT Ltd | Wholesale & retail | 2025 |
| Cura Trading Ltd | Wholesale & retail | 2016 |
| Cure Recruiting Limited | Administrative & support | 2009 |
| Cured by Nature Ltd | Health & social care | 2019 |
| Curiously Consulting Limited | Professional & scientific | 2025 |
| Curl FLO Limited | Wholesale & retail | 2020 |
| Curlee Box Limited | Health & social care | 2018 |
| Curly Riot Ltd | Arts & recreation | 2014 |
| Current Construction and Management Limited | Construction | 2010 |
| Current Healthcare Limited | Health & social care | 2021 |
| Curry Garden Indian Takeaway Ltd | Hospitality | 2020 |
| Cushora Ltd | Wholesale & retail | 2025 |
| Custom Cutters Tree Specialists Limited | Agriculture & fishing | 2006 |
| CUT Zone Ltd | Wholesale & retail | 2020 |
| Cutie Nails Limited | Other services | 2017 |
| Cuts Clothing Limited | Wholesale & retail | 2024 |