| CTW Group Ltd | Wholesale & retail | 2019 |
| CTW Property Investment Ltd | Real estate | 2023 |
| CUB Klub Group Ltd | Financial services | 2021 |
| Cube Garden Rooms Ltd | Construction | 2020 |
| Cube Modular Ltd | Professional & scientific | 2023 |
| Cubertec International Limited | Financial services | 2010 |
| Cubic Industries Ltd | Professional & scientific | 2006 |
| Cubic One Holdings Limited | Financial services | 2020 |
| Cuddles Day Nursery Limited | Education | 1999 |
| Cuillin Advisory Ltd | Professional & scientific | 2024 |
| CUK Association Limited | Other services | 2018 |
| Cullimore Hydraulic Engineering Limited | Professional & scientific | 2014 |
| Cult Classics and Detailing Limited | Wholesale & retail | 2022 |
| Cult Clothing Limited | Professional & scientific | 1977 |
| Cult Commercials Limited | Wholesale & retail | 2023 |
| Cult Upholstery Services Limited | Wholesale & retail | 2020 |
| Cultivate Marketing Ltd | Professional & scientific | 2024 |
| Culture Quarter Ltd | Construction | 2021 |
| Culworth Grounds Solar Limited | Energy | 2013 |
| Curb Properties Holdings Limited | Real estate | 2021 |
| Curb Properties Limited | Real estate | 2018 |
| Curious Cooks Ltd | Education | 2022 |
| Curious Imagination Ltd | Manufacturing | 2024 |
| Curious PR and Events Ltd | Professional & scientific | 2020 |
| Curley & Haines Limited | Professional & scientific | 2021 |
| Curry HUT Gloucestershire Ltd | Hospitality | 2024 |
| Curry Leaves Restaurant Ltd | Hospitality | 2025 |
| Cursed Media Ltd | Information & communication | 2024 |
| Curtis Fitch Limited | Information & communication | 2004 |
| Cushtys Cheltenham Ltd | Other services | 2026 |
| Custodias Technical Limited | Information & communication | 2022 |
| Custom Clean (UK) Limited | Administrative & support | 2013 |
| Custom Remodelling Ltd | Construction | 2023 |
| Customer Reviews Expert Ltd | Professional & scientific | 2024 |
| Customized Drilling Solutions Ltd. | Manufacturing | 2017 |
| Cusulyer Ltd | Administrative & support | 2007 |
| Cutsdean Farms Limited | Agriculture & fishing | 1997 |
| Cutting Edge Marketing Limited | Professional & scientific | 2002 |
| Cuzinaitalialtd Ltd | Hospitality | 2026 |
| Cvdc Limited | Health & social care | 2010 |
| CVR Limited | Information & communication | 2007 |
| CW Elite Ladies Kickboxing Ltd | Arts & recreation | 2024 |
| CW Modelling Ltd | Professional & scientific | 2024 |
| Cwbrst Ltd | Professional & scientific | 2023 |
| Cwcard Ltd | Administrative & support | 2024 |
| CWH Consultants Limited | Professional & scientific | 2020 |
| CWS Scaffolding Ltd | Construction | 2025 |
| CX Strategy Ltd | Professional & scientific | 2023 |
| CX6 Property Holdings Ltd | Real estate | 2021 |
| CY Biopharma Ltd | Manufacturing | 2021 |
| Cyan Crest Properties Limited | Real estate | 2019 |
| Cyan Sky Ltd | Professional & scientific | 2021 |
| Cybaa Ltd | Information & communication | 2025 |
| Cyber Cheltenham CIC | Information & communication | 2017 |
| Cyber Developments Limited | Information & communication | 2024 |
| Cyber Secure Talent Limited | Administrative & support | 2023 |
| Cyber Squadron Ltd | Administrative & support | 2021 |
| Cyber Vigilance Ltd | Information & communication | 2018 |
| Cyberapocalypse Limited | Information & communication | 2020 |
| Cybercentry Limited | Information & communication | 2021 |
| Cyberfleet Solutions Ltd | Administrative & support | 2024 |
| Cyberio Ltd | Administrative & support | 2022 |
| Cyberwhiz Ltd | Information & communication | 2025 |
| Cycling Performance & Health Ltd | Arts & recreation | 2023 |
| Cyclops Plumbing & Heating Limited | Construction | 2007 |
| Cygnus Care Acquisition Limited | Health & social care | 2026 |
| Cygnus Care Holdings Limited | Financial services | 2026 |
| Cygnus Care Operations Limited | Health & social care | 2026 |
| Cygnus INV Ltd | Information & communication | 2020 |
| Cygnus Music Ltd. | Wholesale & retail | 2009 |
| Cygnus Tech Consulting Ltd | Information & communication | 2026 |
| Cylinder Lifter Ltd | Manufacturing | 2025 |
| CYPH3R Limited | Professional & scientific | 2019 |
| Cypress Business Consulting Limited | Wholesale & retail | 2025 |
| Cypress Court (2 Waterloo Street) Management Limited | Households | 1989 |
| Cyril Holland (Southbourne) Limited | Real estate | 1949 |
| Czeska Art Ltd | Other services | 2020 |
| D & a Storage Limited | Transport & logistics | 2003 |
| D & G Ceilings Limited | Construction | 2001 |
| D & H Wheeler Limited | Construction | 2019 |
| D & I Interiors Limited | Construction | 2011 |
| D & J Auto Repairs Ltd | Wholesale & retail | 2018 |
| D & S Property Limited | Real estate | 2003 |
| D B Autorepairs & Paint Ltd | Wholesale & retail | 2012 |
| D Bowler Carpets Limited | Construction | 2008 |
| D C Automotive Limited | Wholesale & retail | 2012 |
| D Fraser Consulting Ltd | Professional & scientific | 2019 |
| D J Parello Limited | Financial services | 2012 |
| D M Dickenson Transport Limited | Transport & logistics | 2009 |
| D S Agencies Limited | Wholesale & retail | 2012 |
| D&D Properties (Cheltenham) Ltd | Financial services | 2013 |
| D&G Contracting Limited | Construction | 2016 |
| D&G Installations Ltd | Construction | 2016 |
| D&G Karein Ltd | Health & social care | 2021 |
| D&Go Limited | Professional & scientific | 2016 |
| D&H Motors (UK) Ltd | Wholesale & retail | 2011 |
| D&H Transport Ltd | Transport & logistics | 2025 |
| D&L Cheltenham Ltd | Real estate | 2026 |
| D&T Installations Ltd | Construction | 2026 |
| D-Carpentry & Joinery Limited | Construction | 2017 |