| Rivington Holdings Ltd | Wholesale & retail | 2020 |
| RON Thomas Electrical Limited | Construction | 2001 |
| Rosmay Ltd | Information & communication | 2024 |
| Saint Cadfans Lodge Limited | Hospitality | 2022 |
| Simply Wild Limited | Agriculture & fishing | 2017 |
| Smallest in the World Limited | Administrative & support | 2022 |
| South Box Ltd | Hospitality | 2021 |
| Spencer Pughe Associates Ltd | Professional & scientific | 2022 |
| Star Barber 37 Ltd | Other services | 2025 |
| Storm & Lighthouse Ltd | Wholesale & retail | 2014 |
| Storylight Candles Ltd | Manufacturing | 2024 |
| Talyllyn Railway Preservation Society | Arts & recreation | 2024 |
| THE Magic Lantern Limited | Information & communication | 2016 |
| THE Talyllyn Railway Company | | 1865 |
| Tidy Games Ltd | Information & communication | 2019 |
| TOM Cave Racing Ltd | Professional & scientific | 2024 |
| Towyn Wholesale Meat Company Limited | Hospitality | 1954 |
| Troed Y Foel Livestock Ltd | Agriculture & fishing | 2020 |
| Tynllwyn Caravan Park Limited | Hospitality | 2005 |
| Tywyn Bakery Limited | Wholesale & retail | 2011 |
| Tywyn Desserts Ltd | Hospitality | 2023 |
| Tywyn Glass & Construction Limited | Construction | 2020 |
| Tywyn Holdings Limited | Real estate | 2022 |
| Tywyn Tools Limited | Manufacturing | 2023 |
| Tywyn Valeting Hand Car Wash Ltd | Administrative & support | 2025 |
| Urban Desert Ltd | Manufacturing | 2021 |
| W Hesleton Engineering Ltd | Other services | 2015 |
| White Beetle Limited | Information & communication | 2005 |
| Will LET Ltd | Real estate | 2017 |
| Y Ganolfan Bryncrug Community Centre Ltd | Other services | 2014 |
| Ysguboriau Caravan Park Ltd | Hospitality | 2013 |