| Cmvc Limited | Hospitality | 2023 |
| Coastal Capital Investments Limited | Real estate | 2023 |
| Cobb & Finch Trading Associates Limited | Wholesale & retail | 2020 |
| Cochrane Limited | Construction | 2023 |
| Cockeram Contractors Ltd | Construction | 2026 |
| Colin G Jones Agri Supplies Ltd | Agriculture & fishing | 2016 |
| Color Court Limited | Other services | 2016 |
| Commercial Kitchen Construct Ltd | Wholesale & retail | 2024 |
| Concept Twenty Five Limited | Real estate | 2025 |
| Considering Curriculum Ltd | Education | 2019 |
| Construction Quality Services Ltd | Construction | 2026 |
| Consultingroom.Com Limited | Information & communication | 2002 |
| Copscymru Casting Limited | Information & communication | 2026 |
| Coronation Consultants Limited | Professional & scientific | 2024 |
| Coulton Enterprises Ltd | Financial services | 2020 |
| Covsec Ltd. | Administrative & support | 2013 |
| CR Exim Ltd | Wholesale & retail | 2025 |
| CR Storage Solutions Limited | Transport & logistics | 2024 |
| Crazy Rhythm Music Limited | Arts & recreation | 2002 |
| Creatable Print Ltd | Manufacturing | 2023 |
| Cresco Projects Limited | Professional & scientific | 2019 |
| Crewin Online Ltd | Administrative & support | 2022 |
| Crick Care Home Ltd | Health & social care | 2023 |
| Criticalplace Limited | Extraterritorial | 1996 |
| Croom Concrete UK Ltd | Manufacturing | 2018 |
| Cropthorne Electrical Services Limited | Professional & scientific | 2007 |
| Crossway Nursery Group Limited | Health & social care | 2016 |
| Crown and Glory Accessories Limited | Manufacturing | 2016 |
| Crown Mews (Audlem) Management Company Limited | Real estate | 2002 |
| Crusader Design Limited | Professional & scientific | 2018 |
| Cryosport Recovery Limited | Health & social care | 2023 |
| Crystal Clear Construction Ltd | Construction | 2025 |
| CSD Accounts Limited | Professional & scientific | 2009 |
| Cubecave Ltd | Transport & logistics | 2019 |
| Culture Craft Game Ltd | Manufacturing | 2023 |
| CUP Coffeee Ltd | Wholesale & retail | 2025 |
| Curry Mahal Caldicot Ltd | Hospitality | 2019 |
| Custom Business Services Limited | Professional & scientific | 2012 |
| Cwbs Carpentry & Building Ltd | Construction | 2021 |
| Cwningen WEN Limited | Information & communication | 2019 |
| D & a Property Holdings Ltd | Households | 2021 |
| D & C Wong Properties Limited | Real estate | 2015 |
| D and C Plumbing and Heating Solutions Limited | Construction | 2021 |
| D C Transport (Newport) Limited | Transport & logistics | 2005 |
| D H Jones Driver Training Limited | Other services | 2004 |
| D&T Recovery Limited | Transport & logistics | 2016 |
| D.B.O. Management Limited | Professional & scientific | 2020 |
| D2 Steel Ltd | Construction | 2023 |
| D6 Holdings Limited | Real estate | 2026 |
| David Croft Electrical Ltd | Construction | 2019 |
| Davis & Sons (Caldicot) Limited | Real estate | 2006 |
| DC Software Limited | Information & communication | 2019 |
| Dependable Installations Limited | Construction | 2024 |
| Derma-Aesthetics (SW) Ltd | Health & social care | 2025 |
| Development Consult Ltd | Real estate | 2006 |
| Development Through Sports Limited | Extraterritorial | 2019 |
| DG Productions (UK) Limited | Information & communication | 2013 |
| DGS Partnership CYF. | Hospitality | 2023 |
| DH Jones Transport Ltd | Transport & logistics | 2021 |
| Diamond Property Training Group Limited | Education | 2025 |
| Dinky Apps Limited | Information & communication | 2025 |
| Direct Professional Services Limited | Professional & scientific | 2017 |
| Distinct Graphics Limited | Professional & scientific | 2021 |
| DKG Project Developments Ltd | Construction | 2022 |
| DMS Auto Services Limited | Wholesale & retail | 2002 |
| Dobrin Lion Properties Limited | Real estate | 2024 |
| Doggy Daycare Penhow Limited | Other services | 2016 |
| DOOR2DOOR Limited | Administrative & support | 2002 |
| Dovers Lettings Ltd | Real estate | 2025 |
| Drake Consultancy Limited | Professional & scientific | 2012 |
| Dream Nails Caldicot Ltd | Other services | 2022 |
| Dreams Care Homes (Cherry Tree) Limited | Health & social care | 1992 |
| Driverse Ltd | Education | 2025 |
| DSE Power Solutions Limited | Construction | 2013 |
| Dupoll Ltd | Construction | 2021 |
| Dusk Learning Partners Ltd | Professional & scientific | 2026 |
| Duthie Plant Limited | Manufacturing | 2025 |
| E&A Law Limited | Professional & scientific | 2010 |
| E&M Property Developments Ltd | Real estate | 2024 |
| E-Lets Property Limited | Real estate | 2023 |
| EBB Cafe Ltd | Wholesale & retail | 2020 |
| EBH Props Ltd | Professional & scientific | 2025 |
| Eco-Tech Laser Solutions Ltd | Administrative & support | 2025 |
| Eden's Green Residents Company Limited | Households | 2024 |
| Edenstone Developments Limited | Construction | 2003 |
| Edenstone Holdings Limited | Construction | 2002 |
| Edenstone Homes Limited | Construction | 2007 |
| Edenstone Limited | Professional & scientific | 2007 |
| Edenstone Projects Limited | Construction | 2003 |
| Edenstone Property Ventures Limited | Construction | 2004 |
| Edenstone Southern Ltd | Construction | 2004 |
| Edge Media Technology Limited | Information & communication | 1994 |
| Edible Storytelling Limited | Hospitality | 2024 |
| Edwards Engineering Services Ltd | Manufacturing | 2017 |
| EJ Riley Limited | Extraterritorial | 2004 |
| Ellevents Ltd | Hospitality | 2025 |
| Elmes & Co (Properties) Limited | Real estate | 2016 |
| Elsa Properties Limited | Real estate | 2020 |
| Empty Space Productions Ltd | Information & communication | 2024 |
| Esimcoverage Ltd | Information & communication | 2025 |