| THE Tea Emporium Ltd | Wholesale & retail | 2025 |
| THE Tidy Tree Company Limited | Administrative & support | 2003 |
| THE Titanium Group Limited | Administrative & support | 2021 |
| THE Two Bulls Ltd | Hospitality | 2018 |
| THE Wagon Yard Ltd | Wholesale & retail | 2019 |
| THE Waves Bookshop Ltd | Wholesale & retail | 2026 |
| THE White Rock House Residents' Association Limited | Households | 1988 |
| THE Wild Kind Collective CIC | Education | 2026 |
| THE Wing Walk Company Limited | Arts & recreation | 2018 |
| THE Wonder Gift Ltd | Wholesale & retail | 2026 |
| THE Works S E Limited | Administrative & support | 2013 |
| THE Write Path Limited | Information & communication | 2026 |
| THE Yoga Garden Holdings Limited | Other services | 2017 |
| The-Transporter UK Ltd | Transport & logistics | 2011 |
| Theatre Nation Ltd | Arts & recreation | 2017 |
| Thefairyhut Ltd | Wholesale & retail | 2021 |
| Theredandwhite Ltd | Professional & scientific | 2020 |
| They Them Ltd. | Arts & recreation | 2011 |
| Think and HIT Ltd | Other services | 2019 |
| Think Indigo Limited | Professional & scientific | 2005 |
| Think&Thing Limited | Professional & scientific | 2016 |
| This Time Tomorrow Limited | Professional & scientific | 2016 |
| Thorne Close Management Limited | Households | 2017 |
| Three Streams Sussex Community Interest Company | Education | 2018 |
| Throughthedoor Limited | Professional & scientific | 2022 |
| Thunderline Care Ltd | Administrative & support | 2025 |
| Tigfusion Limited | Manufacturing | 2013 |
| Tilekiln Community Centre and Social Club CIC | Other services | 2015 |
| Tillingham Life Ltd | Administrative & support | 2013 |
| Tillington Terrace Residents Limited | Households | 2004 |
| Timber Frame IT (South East) Limited | Construction | 2010 |
| Tingz Properties Ltd | Real estate | 2019 |
| Titanium Locksmiths Ltd | Professional & scientific | 2021 |
| Titanium Training Solutions Ltd | Education | 2022 |
| TJB Studio Ltd | Professional & scientific | 2026 |
| TLC Tax Ltd | Professional & scientific | 2025 |
| TM Roofing Southern Limited | Construction | 2018 |
| TMD Defenders Ltd | Wholesale & retail | 2026 |
| TMG Plumbing & Mechanical Services Ltd | Construction | 2019 |
| TN35 Plumbing and Chlorination Services Ltd | Construction | 2020 |
| Tobo Limited | Real estate | 2019 |
| TOM Neal Services Limited | Construction | 2006 |
| Torch Sports Management Limited | Professional & scientific | 2026 |
| Torfield Management Limited | Households | 2001 |
| Total Creative Freedom Ltd | Arts & recreation | 2010 |
| Total Re-Point Limited | Construction | 2021 |
| Town and Country Domestic Staff Limited | Administrative & support | 2014 |
| Town and Country Nannies Limited | Extraterritorial | 2024 |
| Town Trip Ltd | Transport & logistics | 2014 |
| TQ Design & Build Ltd | Construction | 2022 |
| TQ Mechanix Ltd | Wholesale & retail | 2021 |
| Tracy NBT Welch Ltd | Health & social care | 2025 |
| Trader Hastings Limited | Hospitality | 2025 |
| Tradewinds Travel Holidays Limited | Other services | 2019 |
| Trai Ltd | Information & communication | 2025 |
| Training Sussex Ltd | Education | 2023 |
| Trans Lives CIC | Information & communication | 2025 |
| Trans Pride Hastings CIC | Other services | 2023 |
| Transport Events Group Limited | Administrative & support | 2026 |
| TRC Garden Services Ltd | Administrative & support | 2013 |
| Treatbox Holdings Ltd | Real estate | 2025 |
| Treatbox Limited | Wholesale & retail | 2018 |
| Trevor Puttick Consultancy Limited | Professional & scientific | 2024 |
| Triangle Fire Group Limited | Financial services | 2020 |
| Triangle Fire Systems Limited | Construction | 2006 |
| Tricorn Media Limited | Information & communication | 1997 |
| Trifle Media Ltd | Information & communication | 2018 |
| Triple B Development Ltd | Real estate | 2026 |
| Trivela Learning Limited | Education | 2024 |
| Trooperbar Ltd. | Information & communication | 2025 |
| TRP Accountancy Ltd | Professional & scientific | 2016 |
| True Level Art Handling Ltd | Other services | 2021 |
| True Love Never Dies Ltd | Hospitality | 2022 |
| Truer Words Limited | Information & communication | 2024 |
| Truly Scrumptious (Bexhill) Limited | Hospitality | 2021 |
| Tsuk Ltd | Wholesale & retail | 2019 |
| TSW Auto Repairs Bexhill Limited | Wholesale & retail | 2017 |
| TTV Holding Limited | Real estate | 2025 |
| Tucker Productions Ltd | Information & communication | 2011 |
| Tudor Court RTM Company Ltd | Households | 2016 |
| Tuft Arts Ltd | Education | 2025 |
| TUK TUK Hastings Ltd | Hospitality | 2025 |
| Tulleys Pumpkin Catering Limited | Hospitality | 2022 |
| Tulleys Sunflower Catering Limited | Hospitality | 2022 |
| Tulsi Spice HUT Limited | Hospitality | 2023 |
| Tupps&Co Ltd | Construction | 2025 |
| Tvtuna Ltd | Information & communication | 2018 |
| Twin Foxes Residents Association NO.1 Limited | Real estate | 1998 |
| Two FAT Ladies (Competitions) Limited | Arts & recreation | 2025 |
| Two Towers Trust | Other services | 1995 |
| Tydol Group Ltd | Real estate | 2015 |
| Tydol Healthcare Partnership Limited | Education | 2018 |
| Tyler Investments Limited | Real estate | 2022 |
| UAS Cosmetic Limited | Wholesale & retail | 2025 |
| Ubedullah S Ltd | Wholesale & retail | 2025 |
| Uckfield News Limited | Information & communication | 2025 |
| UK Coach Awards Limited | Administrative & support | 2009 |
| UK Metal Recycling Ltd | Water & waste | 2022 |
| UK Metal Recycling Normandy Ltd | Other services | 2025 |
| Ultrahighvacuum Limited | Professional & scientific | 2001 |