| THE Win-Door Avenue Ltd | Construction | 2023 |
| Thomas Consultancy Ltd | Education | 2006 |
| Thomas Lloyd Mail Order Limited | Manufacturing | 1979 |
| Thoper Limited | Financial services | 2024 |
| Tidy Property Sourcing Ltd | Real estate | 2019 |
| Tidy Ventures Ltd | Education | 2020 |
| TIN CHI Rhys Ltd | Wholesale & retail | 2021 |
| TJ Construct Ltd | Construction | 2025 |
| TON Pentre AFC Community Club | Arts & recreation | 2025 |
| Top Notch Baits Limited | Manufacturing | 2025 |
| Transforma Home Building Services Limited | Construction | 2016 |
| Transforma Home Ltd | Real estate | 2011 |
| Travis Darcy Enterprise Ltd | Hospitality | 2021 |
| Tree Line Solutions Limited | Administrative & support | 2024 |
| Treherbert Fish Bar Ltd | Hospitality | 2023 |
| Treorchy Businessmens Club Ltd | Hospitality | 2023 |
| Treorchy Fish Bar Ltd | Hospitality | 2019 |
| Treorchy Hand Carwash 1 Ltd | Administrative & support | 2026 |
| Treorchy Properties Limited | Construction | 2016 |
| Treorchy Sewing Enterprise Ltd | Administrative & support | 2019 |
| Two Dogs Coffee Roasting Company Ltd | Manufacturing | 2017 |
| TWS Wales Limited | Administrative & support | 2008 |
| Tynewydd Hotel Limited | Hospitality | 2024 |
| Tyrone Owen Limited | Manufacturing | 2014 |
| V W Properties Limited | Real estate | 2015 |
| V.W. Group Limited | Financial services | 2017 |
| Valley Repair Centre Ltd | Other services | 2021 |
| Veritas Peptides Ltd | Professional & scientific | 2026 |
| Vipopt Ltd | Hospitality | 2026 |
| Vision Hair Design 2 Limited | Other services | 2017 |
| Vision Hair Design Limited | Other services | 2004 |
| Vitalise Developments Ltd | Real estate | 2021 |
| Vivienne Evans-Lees Ltd | Information & communication | 2025 |
| VW Bistro Cafe Limited | Hospitality | 2017 |
| VW Cardiff Arms Limited | Financial services | 2017 |
| VW Hotel Bistro Limited | Hospitality | 2017 |
| VW Property Training Ltd | Education | 2023 |
| W a Labouring Ltd | Administrative & support | 2025 |
| W P Investors and Lettings Limited | Real estate | 2015 |
| W P S (Wales) Ltd | Administrative & support | 2014 |
| Watts Scaffolding Services SW Limited | Construction | 2024 |
| West Suffolk Chiro Limited | Health & social care | 2025 |
| West Suffolk Chiropractic Clinic Ltd | Health & social care | 2022 |
| Williams Catering Ltd | Hospitality | 2019 |
| Wise Renewable Energy Ltd | Construction | 2021 |
| Wpil Property Developments Limited | Construction | 2023 |
| Wtow Ltd | Administrative & support | 2014 |
| Xray Portals Ltd | Professional & scientific | 2024 |