| THE Salon Suffolk Limited | Other services | 2025 |
| THE Sandringham Festival of Carriage Driving Ltd | Administrative & support | 2023 |
| THE Secret Distillery Limited | Wholesale & retail | 2023 |
| THE Seed Hunter Ltd | Agriculture & fishing | 2026 |
| THE Small Business School Ltd | Education | 2020 |
| THE Small Tree Company (Suffolk) Ltd | Administrative & support | 2024 |
| THE Socius Group Ltd | Professional & scientific | 2019 |
| THE Spirit of Life Productions Limited | Other services | 2020 |
| THE Suffolk Smoke Company Ltd | Hospitality | 2021 |
| THE Suffolk Wild Flour Pizza Co Ltd | Hospitality | 2026 |
| THE Swallow Sidecar & Coachbuilding Company Ltd | Professional & scientific | 2020 |
| THE Testing Factory Limited | Information & communication | 2015 |
| THE Thatch and TAP Ltd | Hospitality | 2026 |
| THE Trade Inn Stowmarket Partnership LP | | 2013 |
| THE Turquoise Collection Ltd | Administrative & support | 2008 |
| THE VR Sphere Ltd | Arts & recreation | 2024 |
| THE Wellness Sanctuary Suffolk Limited | Health & social care | 2024 |
| THE Wine Depot Ltd | Wholesale & retail | 2026 |
| THE Woolpack Inn (Debenham) Limited | Hospitality | 2014 |
| THE Young Buzzers LLP | | 2023 |
| Thelittletrendbook Ltd | Extraterritorial | 2019 |
| Theobald Architectural Technology Limited | Professional & scientific | 2021 |
| Thinktech Strategy Limited | Professional & scientific | 2024 |
| This Way UP Community Interest Company | Professional & scientific | 2023 |
| Thomlinson Wealth Management Limited | Professional & scientific | 2020 |
| Three & a Half Roads (Stowmarket) Limited | Households | 1995 |
| Three Bees Property Ltd | Households | 2022 |
| Thrive Business Consultancy and Accounts Limited | Professional & scientific | 2026 |
| Thrive Nutrition Ltd | Professional & scientific | 2024 |
| Tiboc Ltd | Construction | 2014 |
| TIE Property Limited | Real estate | 2021 |
| Tiron Construction Ltd | Construction | 2022 |
| Titchberry Holdings Limited | Financial services | 2025 |
| Titchberry Limited | Professional & scientific | 2019 |
| Titchberry Property Limited | Real estate | 2020 |
| TKW Automotive Limited | Wholesale & retail | 2022 |
| TLC Productions Limited | Arts & recreation | 2022 |
| TMS Insight [Global] Ltd | Professional & scientific | 2013 |
| TO the Line Contractors Limited | Construction | 2025 |
| Together Bookkeeping Ltd | Professional & scientific | 2021 |
| Tollemache Farms Limited | Agriculture & fishing | 1970 |
| TOM Searles Fine Art Limited | Arts & recreation | 2024 |
| Tomles Properties Limited | Real estate | 2009 |
| Tony Chitty Limited | Energy | 2009 |
| Tony Prior Limited | Administrative & support | 2004 |
| Toolbox Design Limited | Information & communication | 1996 |
| Top Bins Skip Hire Ltd | Water & waste | 2020 |
| Total Driving (UK) Ltd | Education | 2012 |
| Total Property Ltd | Real estate | 2007 |
| Total Training (UK) Ltd | Education | 2013 |
| Town & Village Landscapes Ltd | Construction | 2018 |
| TPT Homes Ltd | Construction | 2021 |
| Traditional Oak Carpentry Limited | Construction | 2007 |
| Traland LLP | | 2010 |
| Trama International Limited | Professional & scientific | 2015 |
| Tramspread Agri Limited | Manufacturing | 2025 |
| Tramspread Contracting Limited | Administrative & support | 2002 |
| Tramspread LLP | | 2016 |
| Tramspread Slurry Storage Limited | Water & waste | 2006 |
| Transport of One Ltd | Transport & logistics | 2016 |
| Trickers Independent Traders Ltd | Administrative & support | 2024 |
| Triklino Ltd | Real estate | 2025 |
| TRIP4YOU Ltd | Transport & logistics | 2024 |
| Triple 1 Construction Services Ltd. | Construction | 2014 |
| Triple C Automotive Limited | Wholesale & retail | 2023 |
| Triple C Car Sales Limited | Wholesale & retail | 2012 |
| Triple G Consulting Ltd | Professional & scientific | 2017 |
| Tristan Page Limited | Wholesale & retail | 2018 |
| Trojan Building & Construction Limited | Construction | 2014 |
| Truefit Executive Search Limited | Administrative & support | 2024 |
| Trusted Cyber Solutions Limited | Information & communication | 2002 |
| Tsundoku Limited | Information & communication | 2024 |
| Tudor Farms Limited | Agriculture & fishing | 1995 |
| Tudor Sash Windows Limited | Construction | 2013 |
| TW Properties (Eastern) LLP | | 2016 |
| TW Properties 03 Limited | Real estate | 2015 |
| TWB Brickwork Ltd | Construction | 2006 |
| Twj's Services Limited | Administrative & support | 2025 |
| Uncut Soundsystem Ltd | Arts & recreation | 2019 |
| Unity Media Eastern Limited | Professional & scientific | 2015 |
| Unityvolt Solutions Ltd | Professional & scientific | 2025 |
| Unomee Limited | Professional & scientific | 2008 |
| Urban Organic London Ltd | Administrative & support | 2015 |
| Urban Panda Vegetation Specialists Ltd | Administrative & support | 2020 |
| Ursa Projects Ltd | Real estate | 2024 |
| Utility Services Group Ltd | Construction | 2023 |
| V & L Maintenance Solutions Ltd | Construction | 2025 |
| V Cracknell and SON (Housing) Limited | Real estate | 2023 |
| V Cracknell and SON Limited | Water & waste | 2010 |
| Valance Games Ltd | Information & communication | 2025 |
| Valiant Talent Limited | Professional & scientific | 2026 |
| Valley Farm Poultry Ltd | Agriculture & fishing | 2003 |
| Valmex Distribution Ltd | Wholesale & retail | 2021 |
| Valuebull Ventures Limited | Professional & scientific | 2014 |
| Vantage Equestrian Ltd | Arts & recreation | 2024 |
| Vaquita Apparel Ltd | Manufacturing | 2021 |
| Vartan Consultancy Limited | Extraterritorial | 2018 |
| Vartan Limited | Extraterritorial | 2018 |
| VDN Construction Ltd | Construction | 2022 |
| Veedeebee Limited | Professional & scientific | 2010 |