| C F Roofing (Pembs) Limited | Construction | 2016 |
| C Jones Research CYF. | Information & communication | 2024 |
| C K Scaffolding Pembs Limited | Construction | 2019 |
| C8 Property Ltd | Real estate | 2024 |
| Cafe 19-21 Quay Street Ltd | Hospitality | 2016 |
| Camrose Vintage Working Day | Administrative & support | 2004 |
| CAP and Stem Ltd | Agriculture & fishing | 2025 |
| Cardigan Metal Recycling Ltd | Water & waste | 2022 |
| Carmarthenshire Herald Limited | Information & communication | 2015 |
| Carpet Spoken Word Ltd | Arts & recreation | 2019 |
| Cartref Pembrokeshire Ltd | Hospitality | 2021 |
| Cash Cash Comp Limited | Arts & recreation | 2025 |
| Castle Hall Management Company Limited | Extraterritorial | 2021 |
| Castle Hall Road Limited | Real estate | 1994 |
| Castle Printwear Ltd | Manufacturing | 2026 |
| Celtic Camping Ltd | Hospitality | 2014 |
| Celtic Contracting Limited | Agriculture & fishing | 2015 |
| Celtic Residential Care Limited | Administrative & support | 2007 |
| Celtic Scaffolding Solutions Ltd | Construction | 2026 |
| Celtic Scooters & Motorcycles Limited | Wholesale & retail | 2012 |
| Celtic Vintners Limited | Professional & scientific | 2012 |
| Centre Stage Creative Limited | Information & communication | 2015 |
| Cgjg Services Limited | Other services | 2020 |
| Charcoal Grill Ltd | Hospitality | 2025 |
| Charcoal Grill Neyland Ltd | Hospitality | 2026 |
| Chardon Property Limited | Real estate | 2023 |
| Charleshaus Ltd | Construction | 2025 |
| Chartaid Limited | Professional & scientific | 2002 |
| Chopstock Ltd | Information & communication | 2018 |
| Christie Louise Coombs Limited | Professional & scientific | 2019 |
| Citizens Guard Limited | Administrative & support | 2020 |
| CL Wicks Safety Ltd | Construction | 2023 |
| Clean CUT Trees Ltd | Agriculture & fishing | 2020 |
| Cleddau Development Limited | Professional & scientific | 2010 |
| Cleddau Enterprises Limited | Professional & scientific | 2005 |
| Cleddau Farming Limited | Agriculture & fishing | 2012 |
| Cleddau Financial Services Limited | Financial services | 1998 |
| Cleddau Memorials Limited | Other services | 2014 |
| Cloud Nine Accounts Ltd | Professional & scientific | 2022 |
| Coast Cleaning Pembrokeshire Ltd | Households | 2025 |
| Coast Event Partners Ltd | Hospitality | 2026 |
| Coastie Cottage Ltd | Real estate | 2026 |
| Coco's Pembs Ltd | Hospitality | 2018 |
| Codds Ltd | Households | 2024 |
| Completely Rented Limited | Real estate | 2025 |
| Compton Technical Services Limited | Professional & scientific | 2026 |
| Consort Equipment Products Limited | Manufacturing | 1996 |
| Consult ME Pembs Limited | Professional & scientific | 2023 |
| Contract Fire and Safety Limited | Professional & scientific | 1995 |
| Cookson Enterprises Limited | Other services | 2016 |
| Corporate Soul Limited | Health & social care | 2016 |
| CPD Fit Limited | Other services | 2023 |
| Craig James Wealth Management Ltd | Professional & scientific | 2021 |
| Crazy BUT True Ltd | Wholesale & retail | 2008 |
| Cream Business Associates Limited | Professional & scientific | 2007 |
| Creamside Developments Limited | Construction | 2023 |
| Creamside Holdings Limited | Financial services | 2023 |
| Crosshart Limited | Education | 2014 |
| Crown Safe Associates Ltd | Professional & scientific | 2025 |
| CUB3D Ltd | Professional & scientific | 2019 |
| Curry's Building & Plastering Contractors Ltd | Construction | 2019 |
| CYT Plastering & Building Limited | Construction | 2021 |
| D & M Electrix Limited | Construction | 2008 |
| D & M Services (Pembs) Limited | Extraterritorial | 2010 |
| D a Inspection Limited | Construction | 2019 |
| D. Hunniford Inspection Ltd | Administrative & support | 2011 |
| D2D Components Limited | Administrative & support | 2017 |
| DA Rosemeyer Groundworks Ltd | Construction | 2024 |
| Daily Convenience Ltd | Wholesale & retail | 2025 |
| Daisy Jack Magic Limited | Administrative & support | 2000 |
| Dale Boathouse Cafe Ltd | Hospitality | 2020 |
| Dale Marine Limited | Other services | 1989 |
| Dale Sailing Co. Limited | Manufacturing | 1974 |
| Danny Colls Inspection Limited | Professional & scientific | 2015 |
| Dansie Software Limited | Information & communication | 2021 |
| Darth Marty Media Ltd | Professional & scientific | 2025 |
| Davey Site Services Limited | Construction | 1986 |
| Davies Edwards Limited | Construction | 2010 |
| Davies Fuels Pembrokeshire Limited | Wholesale & retail | 2024 |
| DB Property (Cambridge) Limited | Real estate | 2010 |
| DC Stores Group Limited | Wholesale & retail | 2024 |
| DE Interiors Limited | Construction | 2020 |
| De-Val-Ca Engineering Limited | | 1980 |
| Dead Sea Design Ltd | Professional & scientific | 2021 |
| Debt Ease Ltd | Information & communication | 2019 |
| Deemshill Farms Limited | Agriculture & fishing | 1955 |
| Delphy Hair & Aesthetics Ltd | Other services | 2025 |
| Dewslake Camping Limited | Hospitality | 2021 |
| Dewslake Limited | Real estate | 2011 |
| Dila 02 Limited | Hospitality | 2026 |
| Dirty Blooms Floral Boutique Ltd | Wholesale & retail | 2025 |
| Divinity Entertainment Ltd | Other services | 2024 |
| DJD Developments Ltd | Construction | 2025 |
| DJH Controls Limited | Professional & scientific | 2009 |
| DLR Consultants Limited | Information & communication | 2009 |
| Doodles Childcare Ltd | Education | 2025 |
| Doug Evens Photo Video Ltd | Information & communication | 2014 |
| DOWN2EARTH Merlin's Bridge CIC | Administrative & support | 2025 |
| DP Stoves & Fireplaces Ltd | Construction | 2021 |
| DR L Burrow Limited | Health & social care | 2015 |