| Coffee Addiction Ltd | Wholesale & retail | 2022 |
| Coffee With Desserts Ltd | Hospitality | 2025 |
| Cofferia Limited | Wholesale & retail | 2026 |
| Coffi Club Ltd | Hospitality | 2026 |
| Coghlan Lodges PVT Ltd | Health & social care | 2019 |
| Cogniforma H Limited | Financial services | 2025 |
| Cogniforma Ltd | Information & communication | 2023 |
| Cognivis Limited | Wholesale & retail | 2025 |
| Cohen Cardona Films Limited | Arts & recreation | 2025 |
| Cohen Care Ltd | Health & social care | 2020 |
| Coin Pro Limited | Information & communication | 2021 |
| Colaint Properties Ltd | Real estate | 2024 |
| Colaint Technology Ltd | Information & communication | 2018 |
| Colaz Franchising Ltd | Professional & scientific | 2013 |
| Cold Street Limited | Wholesale & retail | 2019 |
| Coldman Haulage Limited | Transport & logistics | 2011 |
| Coles Roofing Limited | Construction | 2013 |
| Coles Roofing Southern Ltd | Construction | 2025 |
| Collections & Recoveries Europe Limited | Professional & scientific | 2010 |
| Collinear Limited | Professional & scientific | 2012 |
| Collingwood Health Ltd | Health & social care | 2011 |
| Colnbrook Coffee House Ltd | Hospitality | 2025 |
| Colnbrook Couriers Ltd | Transport & logistics | 2019 |
| Colnbrook Estates Limited | Transport & logistics | 1968 |
| Colnbrook Food and Wine Ltd | Wholesale & retail | 2022 |
| Colnbrook Holdings Ltd | Transport & logistics | 2024 |
| Colnbrook Lodge Limited | Real estate | 1997 |
| Colnbrook Pallets Limited | Wholesale & retail | 2025 |
| Colnbrookproperties Ltd | Real estate | 2024 |
| Colney Hatch Dental Practice Ltd | Health & social care | 2007 |
| Colorgram Designs UK Ltd | Manufacturing | 2024 |
| Colour Wheel North Surrey Ltd | Arts & recreation | 2017 |
| Colsen Industries Limited | Wholesale & retail | 1993 |
| Colt DE RAI Meat House Ltd | Manufacturing | 2024 |
| Coltsview Property Limited | Real estate | 2013 |
| Columbia Europe Ltd | Wholesale & retail | 2009 |
| Com-Net (London) Limited | Real estate | 1999 |
| Combat Academy Ltd | Education | 2024 |
| Combey Company Limited | Wholesale & retail | 2018 |
| Comfo Cars Ltd | Transport & logistics | 2021 |
| Comfort Care and Health Ltd | Health & social care | 2023 |
| Comfort Care Services (UK) Ltd | Health & social care | 2004 |
| Comfort Clean Ltd | Administrative & support | 2026 |
| Comfort Coaches Limited | Transport & logistics | 2011 |
| Comfort Eco Grants Ltd | Construction | 2024 |
| Comfort Oulook Ltd | Wholesale & retail | 2025 |
| Comfort Wear Clothing Ltd | Wholesale & retail | 2022 |
| COMFORT24HOURS Healthcare Ltd | Health & social care | 2024 |
| Comfortbridge Healthcare Recruitment Ltd | Administrative & support | 2026 |
| Comfynest Beddings Limited | Wholesale & retail | 2026 |
| Commcen Engineering Limited | Professional & scientific | 2019 |
| Commerceaza Ltd | Wholesale & retail | 2026 |
| Commercial KP Ltd | Wholesale & retail | 2017 |
| Commercial Rental UK Ltd | Real estate | 2026 |
| Commercial Vehicles Ltd | Administrative & support | 2025 |
| Commsreach Ltd | Information & communication | 2025 |
| Communican Ltd | Education | 2024 |
| Communikate Limited | Other services | 2017 |
| Communique Associates (UK) Limited | Information & communication | 2004 |
| Communiteks Ltd | Wholesale & retail | 2016 |
| Community Calm CIC | Other services | 2024 |
| Community Chiropractors Limited | Health & social care | 2022 |
| Community Coders Ltd | Information & communication | 2014 |
| Community Frame Ltd | Information & communication | 2025 |
| Community Online CIC | Information & communication | 2021 |
| Compact Home Care Limited | Health & social care | 2024 |
| Compact Sales & Lettings Limited | Real estate | 2020 |
| Compact Trading Limited | Wholesale & retail | 2024 |
| Compare Geek Ltd | Financial services | 2019 |
| Compare Parking Prices Ltd | Transport & logistics | 2022 |
| Compare Switch Ltd | Information & communication | 2022 |
| Compare the Airport Parking.Com Limited | Administrative & support | 2021 |
| Compass Logistics International Ltd | Transport & logistics | 2017 |
| Compass Radio Cars Ltd | Transport & logistics | 2007 |
| Competent Technologies Ltd | Information & communication | 2015 |
| Competitive Cars Ltd | Wholesale & retail | 2017 |
| Complete Circle Limited | Administrative & support | 2020 |
| Complete Clear Logistics Ltd | Transport & logistics | 2021 |
| Complete Foundations Systems Limited | Wholesale & retail | 2007 |
| Complete Party Services (Slough) Limited | Wholesale & retail | 2008 |
| Complete Production Services Limited | Hospitality | 2008 |
| Complete Staffing Ltd | Administrative & support | 2018 |
| Completesuccess Tuition Ltd | Education | 2025 |
| Compliance Search System Limited | Information & communication | 2019 |
| Components Automotives 73 Limited | Manufacturing | 1973 |
| Composer Roofing Ltd | Construction | 2025 |
| Composite Manufacturing and Design Ltd | Manufacturing | 2010 |
| Compound Tech Ltd | Professional & scientific | 2024 |
| Compris Channel Management Limited | Wholesale & retail | 2012 |
| Computer Systems for Distribution Limited | Information & communication | 1989 |
| Concept C Consultancy Limited | Professional & scientific | 2023 |
| Concept Health Care Services Ltd | Administrative & support | 2023 |
| Conception Collective Limited | Health & social care | 2024 |
| Concrete Buddies Ltd | Construction | 2023 |
| Concrete LAY Ltd | Construction | 2017 |
| Concrete LAY Structure Ltd | Construction | 2022 |
| Concrete MIX Master Limited | Manufacturing | 2022 |
| Conduit.Io Ltd | Information & communication | 2022 |
| Conekta Limited | Construction | 2022 |
| Conferus Homes Limited | Real estate | 2022 |