| Costy Driving School Limited | Education | 2021 |
| Costy&Xjd Ltd | Construction | 2025 |
| Coswise Food & Wines Limited | Wholesale & retail | 2016 |
| Cosy Blinds Ltd | Wholesale & retail | 2019 |
| Cosy Club Sofas Ltd | Wholesale & retail | 2024 |
| Cosy Cushions Limited | Wholesale & retail | 2017 |
| Cosy Heaven Ltd | Hospitality | 2026 |
| Cosy Housing Limited | Real estate | 2026 |
| Cosy Living Homes Ltd | Real estate | 2025 |
| Cosy Logistics Ltd | Transport & logistics | 2026 |
| Cosycrib Limited | Real estate | 2023 |
| COSYHAVEN32 Ltd | Real estate | 2024 |
| Cote Designs Ltd | Information & communication | 2021 |
| Cotef Electrical Ltd | Construction | 2026 |
| Cotham OFF Licence Ltd | Wholesale & retail | 2024 |
| Cotmore Park Thame Management Company Ltd | Real estate | 2015 |
| Cots and Crayons Ltd | Health & social care | 2024 |
| Cotswold Access Chambers Limited | Manufacturing | 2019 |
| Cotswold Culinary College Ltd | Education | 2025 |
| Cotswold Dairy Farm Ltd | Wholesale & retail | 2025 |
| Cotswold Heating Accessories Limited | Wholesale & retail | 2025 |
| Cotswold Inns Ltd | Hospitality | 2024 |
| Cotswold Leisure Ltd | Hospitality | 2020 |
| Cotswold LOG Cabins Limited | Administrative & support | 2022 |
| Cotswold Ocularis Ltd | Health & social care | 2021 |
| Cotswold Penstocks Limited | Manufacturing | 2019 |
| Cotswold Pipelines Limited | Manufacturing | 2019 |
| Cotswold Services Limited | Construction | 2023 |
| Cotswold Valves Limited | Wholesale & retail | 1979 |
| Cotswolds Cottage Holiday Homes Limited | Real estate | 2021 |
| Cottage Boarding Kennels Limited | Agriculture & fishing | 2025 |
| Cottage Close Maintenance Company Limited | Households | 1967 |
| Cottage Theory Ltd | Wholesale & retail | 2025 |
| Cottageburgerss Ltd | Hospitality | 2025 |
| Cottam & Sons Removals LLP | | 2017 |
| Cotterdale Investments Limited | Real estate | 2013 |
| Cotteridge Community Investment District Limited | Other services | 2026 |
| Cotteridge Fine Foods Limited | Wholesale & retail | 2018 |
| Cotteridge Flooring Ltd | Wholesale & retail | 2025 |
| Cotteridge Foods Limited | Hospitality | 2017 |
| Cotteridge Glass & Glazing (Bham) Limited | Transport & logistics | 2007 |
| Cotteridge Nails & Spa Ltd | Other services | 2024 |
| Cotteridge Tyre Services Ltd | Wholesale & retail | 2026 |
| Cotteridge Tyres Ltd | Wholesale & retail | 2024 |
| Cottesbrooke Infant and Nursery School | Education | 2014 |
| Cottesloe Property Company Limited | Professional & scientific | 1970 |
| Cotton Securities Limited | Real estate | 2014 |
| Cotton Tails Hagley Limited | Other services | 2018 |
| Cotton Tails Nurseries Limited | Health & social care | 2001 |
| Cotton&Fiber Ltd | Wholesale & retail | 2021 |
| COTTON21 Ltd | Wholesale & retail | 2022 |
| Cottons Auctioneers Limited | Real estate | 2003 |
| Cottons Estate Agents Limited | Real estate | 2003 |
| Cottons Management Services Limited | Real estate | 2003 |
| Cottons Property Consultants LLP | | 2011 |
| Cottons Residential Lettings Limited | Real estate | 2003 |
| Cottons Surveyors Limited | Real estate | 2003 |
| Cottrells Mews Limited | Real estate | 2000 |
| Cottrill & Associates Limited | Wholesale & retail | 2010 |
| Couch and Sons Ltd | Manufacturing | 2018 |
| Couch Bars Limited | Hospitality | 2019 |
| Couch Craft Ltd | Wholesale & retail | 2021 |
| Cougar Automotive Limited | Wholesale & retail | 2020 |
| Coundon House Gardens Management Limited | Real estate | 2007 |
| Coundon House Management Limited | Real estate | 2001 |
| Counselling and Life Management Ltd | Administrative & support | 2015 |
| Counselling With Holly Ltd | Education | 2024 |
| Count to TEN Ltd | Professional & scientific | 2012 |
| Counter Culture Group Limited | Wholesale & retail | 2020 |
| Counteroll Limited | Information & communication | 2025 |
| Counterpoint IV Limited | Professional & scientific | 2011 |
| Countes Holding Company Ltd | Real estate | 2022 |
| Counting Seconds UK Limited | Administrative & support | 2024 |
| Country Parks Ltd. | Hospitality | 1980 |
| Country Rose Limited | Health & social care | 2018 |
| Country's Pride Ltd | Wholesale & retail | 2019 |
| Countrywide Contract Maintenance Ltd | Construction | 2011 |
| Countrywide Couriers Limited | Transport & logistics | 2025 |
| Countrywide Electrical Services Limited | Construction | 1996 |
| Countrywide Estates (Europe) Limited | Real estate | 2018 |
| Countrywide Estates Partnership LLP | | 2022 |
| Countrywide GAS & Plumbing Limited | Construction | 2025 |
| Countrywide Law Associates Ltd | Professional & scientific | 2011 |
| Countrywide Law Limited | Professional & scientific | 2017 |
| Countrywide Links Limited | Wholesale & retail | 2024 |
| County Leather Goods Ltd | Wholesale & retail | 2025 |
| County Property Solutions Ltd | Construction | 2023 |
| County Resources Limited | Administrative & support | 2015 |
| County Waste Limited | Water & waste | 2001 |
| Countymotors Ltd | Wholesale & retail | 2019 |
| Coupen Creation Limited | Health & social care | 2024 |
| Coupleclean and Logistics Ltd | Transport & logistics | 2025 |
| Coupzon Ltd | Wholesale & retail | 2023 |
| Courageous Consulting Limited | Professional & scientific | 2012 |
| Courgette Social Limited | Administrative & support | 2013 |
| Courier Connect Logistics Ltd | Transport & logistics | 2024 |
| Courier Drops Ltd | Transport & logistics | 2019 |
| Courier Ismail Ltd | Transport & logistics | 2026 |
| Courier KAL Ltd | Transport & logistics | 2026 |
| Courier on Wheels Ltd | Transport & logistics | 2025 |