| Costa's Properties Ltd | Real estate | 2024 |
| CPM (South) Ltd | Construction | 2006 |
| Craft Builders Limited | Construction | 2002 |
| Craft Wales Ltd | Manufacturing | 2005 |
| CRE8 Lettings Limited | Real estate | 2017 |
| Creative Crafts & Engraving Ltd | Wholesale & retail | 2025 |
| Crow Valley Publishing Ltd | Information & communication | 2025 |
| Crucible Exchange Ltd | Manufacturing | 2026 |
| CS Care & Clean Ltd | Administrative & support | 2026 |
| CTH Services Limited | Construction | 2017 |
| CW Panel Wiring Ltd | Manufacturing | 2025 |
| CW Precision Plumbing Ltd | Construction | 2025 |
| CWM Bakery Ltd | Wholesale & retail | 2026 |
| Cwmni AHC Limited | Households | 2017 |
| D Emlyn Lloyd Limited | Wholesale & retail | 2004 |
| D.C. Furber & Sons (Haulage) Limited | | 1974 |
| D.I.Y. Doctor Limited | Information & communication | 2006 |
| Dadson Electrical Limited | Construction | 2016 |
| Dainton Brothers Ltd | Wholesale & retail | 2024 |
| Daljit Films UK Limited | Administrative & support | 2025 |
| Delyn Packaging Limited | Manufacturing | 2002 |
| DH Advisory Services Ltd | Professional & scientific | 2022 |
| DID IT Group Limited | Wholesale & retail | 2022 |
| Didit Ltd | Manufacturing | 2023 |
| DIGI4 Limited | Information & communication | 2016 |
| Digital DAD Official Ltd | Wholesale & retail | 2024 |
| DIN Dins CP Ltd | Hospitality | 2026 |
| DIN Dins GG Ltd | Hospitality | 2026 |
| Din-Din's Food Limited | Hospitality | 2023 |
| DK Project Solutions Ltd | Construction | 2025 |
| DMD Contractors Ltd | Construction | 2021 |
| Doleq Carpets ( Brynmawr) Ltd | Wholesale & retail | 2022 |
| Dotted Properties Ltd | Real estate | 2021 |
| DPR Plumbing and Heating Ltd | Construction | 2022 |
| DRA Property Developments Limited | Real estate | 2022 |
| Draco Carpentry Ltd | Construction | 2026 |
| Dragon Cold Rooms Ltd | Manufacturing | 2017 |
| Dripping MAD Vapes Ltd | Wholesale & retail | 2018 |
| Dust Devils Ltd | Administrative & support | 2024 |
| Dymond & Sons Ltd | Real estate | 2023 |
| Dymond Hurst Ltd | Real estate | 2018 |
| E-Learning Matters Ltd | Education | 2021 |
| Earc Bluebirds Ltd | Construction | 2019 |
| East Wales Food Waste Collections Limited | Extraterritorial | 2014 |
| EDUC8 Assessments Limited | Education | 2010 |
| EDUC8 Employee Ownership Trustee Ltd | Professional & scientific | 2022 |
| EDUC8 Holdings Limited | Administrative & support | 2021 |
| EDUC8 Limited | Education | 2004 |
| EDUC8 Training (England) Limited | Education | 1989 |
| EDUC8 Training Group Limited | Administrative & support | 2017 |
| EK Physiotherapy Ltd | Health & social care | 2024 |
| Elevation Creative Multimedia Ltd | Professional & scientific | 2023 |
| Envy Hair Stuido LA Limited | Other services | 2015 |
| European Traders Limited | Professional & scientific | 1987 |
| Evanest Limited | Professional & scientific | 2010 |
| Evans Tech Limited | Information & communication | 2026 |
| EVE of EVE Ltd | Wholesale & retail | 2022 |
| Evro Consulting Ltd | Professional & scientific | 2025 |
| EVS Groundworks Ltd | Construction | 2026 |
| Exodia Consulting Ltd | Professional & scientific | 2022 |
| Exodia Group Ltd | Financial services | 2022 |
| F C Brooks and Sons Removals and Storage Limited | Transport & logistics | 2016 |
| Felix in the Kitchen Ltd | Hospitality | 2025 |
| Findai Drywall Solutions Ltd | Construction | 2025 |
| Finkamink Limited | Financial services | 2020 |
| Firesealsdirect Limited | Wholesale & retail | 2025 |
| Fish Heating Services Ltd | Construction | 2006 |
| Fish Kitchen 1854 Ltd | Hospitality | 2018 |
| Flawless Cosmetic Medicine Limited | Other services | 2016 |
| Flush Fit Upvc Installations Limited | Construction | 2019 |
| Focused Recruitment (Temps) Limited | Administrative & support | 2007 |
| Football Tourists Limited | Administrative & support | 2023 |
| Fork Truck Express Services Limited | Manufacturing | 2002 |
| Fortis Properties Management Limited | Real estate | 2024 |
| Foxbrown Ltd | Real estate | 2024 |
| Frank Gorham Infrastructure Management Ltd | Construction | 2022 |
| Fred and Lloyd Limited | Transport & logistics | 2013 |
| Fresh N CUT Ltd | Other services | 2024 |
| FSL Software Ltd | Information & communication | 2026 |
| G & L Drainage Ltd | Construction | 2025 |
| G Equipment Solutions Limited | Manufacturing | 2021 |
| G.R Plumbing Merchants Ltd | Construction | 2024 |
| Garethcoffee Limited | Manufacturing | 2022 |
| Gaul Auto Detailing Ltd | Wholesale & retail | 2025 |
| Gavin Brewer Tools Ltd | Wholesale & retail | 2024 |
| GEM Automation Ltd | Professional & scientific | 2017 |
| GET SET Scenery Ltd. | Arts & recreation | 1999 |
| GET SET Storage Limited | Transport & logistics | 2004 |
| GG Hand Car Wash Ltd | Administrative & support | 2024 |
| GK Engineering Consultants Ltd | Professional & scientific | 2025 |
| Glow UP by Kelly Limited | Health & social care | 2025 |
| Godwin Entertainment Ltd | Wholesale & retail | 2025 |
| Grove Lane Properties Ltd | Real estate | 2024 |
| Grvj Limited | Wholesale & retail | 2018 |
| Gryphonn Concrete Products Limited | Transport & logistics | 1983 |
| Gryphonn Quarries Limited | Mining & quarrying | 1986 |
| Gunter Estates Ltd | Real estate | 2026 |
| Gunter Solutions Ltd | Information & communication | 2021 |
| GWY Holdings Ltd | Real estate | 2026 |
| H M J Installations Limited | Construction | 2017 |