| Spick and Span Housekeeping Services Ltd | Administrative & support | 2014 |
| Standard and Servo Electrical Repairs Limited | Manufacturing | 2015 |
| Stevly Holdings Ltd | Financial services | 2025 |
| Stevly Properties Ltd | Real estate | 2020 |
| Stevly Upvc Supply Centre Limited | Manufacturing | 1995 |
| Stonerow Property Management Limited | Real estate | 2016 |
| Storfa Solutions Limited | Professional & scientific | 2019 |
| Stovan Property Management Limited | Real estate | 2025 |
| Supreme Design Flooring Ltd | Construction | 2023 |
| Surfacing Specialist Limited | Construction | 2022 |
| Suzanne Cole Consultancy Limited | Professional & scientific | 2020 |
| TAG Labour Supplies Ltd | Construction | 2020 |
| TAI ARJ Ltd | Administrative & support | 2025 |
| Tech Literacy CIC | Information & communication | 2026 |
| Terry's Patisserie Limited | Manufacturing | 2011 |
| Thani Fuels Limited | Wholesale & retail | 2025 |
| THE Atlas Group SW Ltd | Construction | 2026 |
| THE Cutesy Co Limited | Manufacturing | 2018 |
| THE Darts Dungeon Ltd | Wholesale & retail | 2025 |
| THE Goddery Ltd | Wholesale & retail | 2025 |
| THE Harp Studio CYF | Wholesale & retail | 2014 |
| THE New Continental Cafe Limited | Hospitality | 2004 |
| THE Smoke Asylum Ltd | Wholesale & retail | 2020 |
| THE Square Royale Limited | Hospitality | 2016 |
| THE Welsh Centre for Learning Disability Inclusive Research CIC | Professional & scientific | 2025 |
| Thompson Maintenance Ltd | Administrative & support | 2024 |
| Thriving Communities CIC | Health & social care | 2021 |
| Tj’S Property and Rentals Ltd | Real estate | 2025 |
| Top Notch Rigging Limited | Information & communication | 2021 |
| Torfaen Aggregates Limited | Mining & quarrying | 2025 |
| Town Building Limited | Construction | 2026 |
| Trecco Bay Caravan and Lodge Hire Ltd | Real estate | 2023 |
| Trivium Wealth Ltd | Financial services | 2024 |
| United Aggregates Limited | Professional & scientific | 1974 |
| USA Fried Chicken 12 Ltd | Hospitality | 2026 |
| Valley News ( Bargoed ) Limited | Information & communication | 2012 |
| Valley to Vale Construction Limited | Construction | 2015 |
| Vintique Sales Ltd | Wholesale & retail | 2022 |
| Vision Design Construction Services Limited | Construction | 2023 |
| Voicestory Limited | Information & communication | 2023 |
| W.J.Gardner(Cardiff)Limited | Real estate | 1934 |
| WA Business Services Limited | Other services | 2019 |
| Walkred Limited | Hospitality | 1985 |
| Walksin Limited | Real estate | 1966 |
| Wicked INK Ltd | Arts & recreation | 2020 |
| Wicked Walkies Limited | Agriculture & fishing | 2022 |
| Wildcard Technology Limited | Information & communication | 2024 |
| Willetts Accounting Services Ltd | Professional & scientific | 2019 |
| Williams Carpentry & Building Contractors Limited | Construction | 2007 |
| Willowtree Dachshunds Ltd | Agriculture & fishing | 2021 |
| Y Cwtsh (Bargoed) Ltd | Hospitality | 2026 |
| Yellow River Investments Ltd | Real estate | 2018 |