| Stane Street Investments Limited | Real estate | 1998 |
| Stay in the Beacons Limited | Hospitality | 2022 |
| Stay in the Park Ltd | Hospitality | 2017 |
| Steelfox Ltd | Professional & scientific | 2017 |
| Stewarts Emporium and Community Hub CIC | Wholesale & retail | 2025 |
| Sublime Print Ltd | Manufacturing | 2026 |
| Sudocyber Limited | Professional & scientific | 2021 |
| Sugar Loaf Trading Ltd | Wholesale & retail | 2024 |
| Swansea & Brecon Diocesan Trust Incorporated(The) | Administrative & support | 1926 |
| Swansea and Brecon Diocesan Board of Finance Limited(The) | Other services | 1967 |
| Swansea City Opera & the Opera School Wales | Arts & recreation | 1996 |
| Systemic Policy Partnership LLP | | 2012 |
| T and K Resolutions Ltd | Professional & scientific | 2024 |
| T J Assessments Limited | Education | 2018 |
| T Johnson Construction Limited | Construction | 2024 |
| Tailored Imports Ltd | Wholesale & retail | 2015 |
| Talgarth Airfield Limited | Arts & recreation | 1998 |
| Talk to the Trees Ltd | Other services | 2023 |
| Tall Poppy Transcriptions Limited | Information & communication | 1993 |
| Talybont-On-Usk Energy | Education | 2004 |
| Tangent Partnership Ltd | Other services | 2008 |
| Taste Inn Wales Limited | Professional & scientific | 2005 |
| Tcfmcg Ltd | Professional & scientific | 2025 |
| Teachwales Limited | Education | 2016 |
| Technoplus I. T. Limited | Information & communication | 1998 |
| Tecta Associates Limited | Professional & scientific | 2017 |
| Tegfan Property Limited | Real estate | 2021 |
| Telosai Ltd | Professional & scientific | 2024 |
| Tempest Forensic Accounting Limited | Professional & scientific | 2010 |
| Tempest Forensic Accounting UK LLP | | 2013 |
| TFG Fishing Limited | Wholesale & retail | 2021 |
| THE British Biathlon Union | Arts & recreation | 1996 |
| THE Allergy DRS Ltd | Health & social care | 2018 |
| THE Allt Garage Ltd | Wholesale & retail | 2022 |
| THE Anthony Brandt (Artist): Keppe Foundation | Professional & scientific | 2001 |
| THE Brecknockshire Agricultural Society | Other services | 2004 |
| THE Castle Coaching Inn Limited | Hospitality | 2022 |
| THE Cat N'Tap Ltd | Hospitality | 2025 |
| THE Cat Soup Kitchen Ltd | Hospitality | 2018 |
| THE Cavalry of Heroes Limited | Arts & recreation | 2015 |
| THE Clarence Inn Limited | Hospitality | 2014 |
| THE Country Road 2024 Limited | Hospitality | 2024 |
| THE Dewan Partnership Limited | Professional & scientific | 2015 |
| THE Drovers Arms Limited | Hospitality | 2023 |
| THE Emperor Painter Ltd | Construction | 2025 |
| THE Fermentarium C.I.C. | Hospitality | 2019 |
| THE Fire and Stove Shop Ltd | Construction | 2011 |
| THE Flooring Co by TOM Griffiths Ltd | Wholesale & retail | 2026 |
| THE Foundry Brecon Ltd | Hospitality | 2022 |
| THE Giveaway Bro’S Ltd | Other services | 2025 |
| THE Glass Gramophone Company Limited | Arts & recreation | 1995 |
| THE Griffin Inn (Llyswen) Limited | Hospitality | 2019 |
| THE GURKHA7 Limited | Hospitality | 2025 |
| THE Handyman Service W Limited | Construction | 2021 |
| THE Hive - Busy for Better Lives C.I.C. | Professional & scientific | 2025 |
| THE Ice Cream Bar Limited | Hospitality | 2006 |
| THE Jones Forge Limited | Wholesale & retail | 2025 |
| THE Lake Country House Hotel and Spa Limited | Hospitality | 2016 |
| THE Left Bank Brewing Company Ltd | Manufacturing | 2019 |
| THE Malthouse (Talgarth) Ltd | Hospitality | 2019 |
| THE Muddy Geography Company Limited | Education | 2016 |
| THE Muse Agency Community Interest Company | Education | 2024 |
| THE New Gurkha Inn Ltd | Hospitality | 2017 |
| THE Oxford Boys Limited | Wholesale & retail | 2021 |
| THE Proper Pizza Company Limited | Hospitality | 2010 |
| THE Public House (Bronllys) Limited | Hospitality | 2023 |
| THE Racing Retreat (Lambourn) Limited | Agriculture & fishing | 2025 |
| THE Royal Welsh Regimental Museum Trust | Arts & recreation | 2011 |
| THE Star Inn Brecon Beacons Ltd | Hospitality | 2019 |
| THE Three Horseshoes (Groesffordd) Limited | Hospitality | 2011 |
| THE Tiny Welsh Workshop Ltd | Manufacturing | 2025 |
| THE Tirion Trading Company Limited | Wholesale & retail | 2006 |
| THE UK Loose Leaf Tea Company Ltd | Wholesale & retail | 2017 |
| THE USK (Sennybridge) Limited | Hospitality | 2019 |
| THE Wellsynergy Project CIC | Other services | 2025 |
| THE Wholehouse Holidays Limited | Hospitality | 2022 |
| THE Wilderness Medic Ltd | Health & social care | 2018 |
| THE Windfall Centre C.I.C. | Other services | 2011 |
| THE WYE and USK Foundation | Other services | 1997 |
| Theatr Brycheiniog CYF | Arts & recreation | 1989 |
| Thestovestore Ltd | Wholesale & retail | 2025 |
| Think Expo Logistics Ltd | Transport & logistics | 2020 |
| Think Green Fulfilment Ltd | Administrative & support | 2024 |
| Three Cocks Hotel Ltd | Hospitality | 2020 |
| Three Cocks Vintage Society Limited | Arts & recreation | 1983 |
| Three Horseshoes Felindre Ltd | Hospitality | 2025 |
| Tidy Fellers Limited | Administrative & support | 2017 |
| Tilt House Limited | Other services | 2024 |
| Time Together Contact Centre Ltd | Health & social care | 2022 |
| Tir-Gwallter Farm Limited | Agriculture & fishing | 1964 |
| Tivoli Therapeutic Services Limited | Health & social care | 2016 |
| TO and FRO Approach CIC | Education | 2022 |
| Top Notch Productions (London) Limited | Information & communication | 2015 |
| Tower Cafe ST Mary's Limited | Hospitality | 2011 |
| Tracks Apart Limited | Education | 2008 |
| Transwales Trails Limited | Arts & recreation | 2004 |
| Trebarried Court Management Company Limited | Administrative & support | 1997 |
| Trecastle Eggs Limited | Agriculture & fishing | 2008 |
| Tree to Post Ltd | Professional & scientific | 2019 |
| Tregaer Farm Limited | Agriculture & fishing | 2025 |