| THE Wilbury Clinic Ltd | Health & social care | 2014 |
| THE Witch & the Magician Ltd | Health & social care | 2025 |
| THE Wombat Web Co Ltd | Information & communication | 2025 |
| THE Wood Shelf Company Ltd | Manufacturing | 2024 |
| THE Woodlands Sussex Group Ltd | Real estate | 2025 |
| THE Word (MD) Ltd | Arts & recreation | 2006 |
| THE World's Greatest Events Ltd | Financial services | 2022 |
| THE Wrightymedia Agency Limited | Professional & scientific | 2023 |
| THE Writer’S Mark Limited | Arts & recreation | 2025 |
| THE XY Performance Co Limited | Manufacturing | 2025 |
| THE Young Actors (Group) Limited | Arts & recreation | 2014 |
| THE Yummy Spuddy Company Limited | Manufacturing | 2014 |
| THE9MONTHCLUB Ltd | Other services | 2020 |
| Theatre of Mind Ltd. | Professional & scientific | 2009 |
| Thebloke.Ai Ltd | Information & communication | 2023 |
| Thegreenmarine Limited | Other services | 2007 |
| Theme HQ Industries Limited | Extraterritorial | 2022 |
| Themoneyoffic.Com Ltd | Information & communication | 2021 |
| Theodore Property Investments Limited | Real estate | 2022 |
| Thepropertyfinder LLP | | 2013 |
| Thermal Transfer Label Systems Limited | Professional & scientific | 2000 |
| Theset Restaurants Limited | Hospitality | 2014 |
| Thetatech Ltd | Information & communication | 2020 |
| Think Clothing Ltd | Manufacturing | 2023 |
| Think Kinder Ltd | Public administration | 2024 |
| Think Office Space Ltd | Administrative & support | 2018 |
| Think Search Digital Limited | Information & communication | 2013 |
| This IS Publicity Limited | Professional & scientific | 2014 |
| This IS Radish Ltd | Wholesale & retail | 2015 |
| This IS Wyld Art | Arts & recreation | 2016 |
| This IS Wyld Ltd | Arts & recreation | 2013 |
| This TOO IS Real Ltd | Professional & scientific | 2016 |
| This Woman's Work Ltd | Administrative & support | 2017 |
| This.Property Enterprise Ltd | Real estate | 2024 |
| Thisisnottherapy Ltd | Health & social care | 2025 |
| Thomas & Sons Holdings Ltd | Financial services | 2018 |
| Thomas Door and Window Controls Limited | Administrative & support | 2002 |
| Thomas Locksmiths Limited | Other services | 1982 |
| Thomdoor Investments Limited | Real estate | 2002 |
| Thomtax Limited | Professional & scientific | 2021 |
| Thornett Capital Limited | Real estate | 2025 |
| Thoughtful Consultancy Ltd | Professional & scientific | 2021 |
| Thoughtful Supermarket Ltd | Hospitality | 2018 |
| Thread PR Ltd | Professional & scientific | 2025 |
| Three ACT Story Ltd | Professional & scientific | 2024 |
| Three Angels Boutique Ltd | Wholesale & retail | 2023 |
| Three Angels Interiors Ltd | Wholesale & retail | 2024 |
| Three Counties Legal Services Limited | Professional & scientific | 2022 |
| Three Fusils Limited | Information & communication | 2011 |
| Three Monkeys Bar Kitchen Ltd | Hospitality | 2019 |
| Three Point Five Ltd | Education | 2016 |
| Three ST. Aubyn's Management Limited | Households | 1978 |
| Threeways RUM Limited | Wholesale & retail | 2020 |
| Thrive Supported Care Ltd | Health & social care | 2022 |
| Thumane Select Limited | Health & social care | 2026 |
| Thunderstone Productions Ltd | Information & communication | 2024 |
| Thyme Property Developments Limited | Real estate | 2004 |
| Tiali Investments Ltd | Real estate | 2021 |
| Tickle Limited | Professional & scientific | 2012 |
| Tiemann & Co Limited | Professional & scientific | 2017 |
| Tier 1 Plumbing Ltd | Construction | 2018 |
| Tiger Kaplan Ltd | Wholesale & retail | 2021 |
| Tiger Lounge 182 Limited | Hospitality | 2024 |
| Tiger Snake Incentives Limited | Wholesale & retail | 2010 |
| Tiger Taxis Limited | Transport & logistics | 1990 |
| Tijs Bauer Design & Build Limited | Construction | 2016 |
| Tillier Property Limited | Real estate | 2018 |
| TIM Larcombe Music Ltd | Information & communication | 2020 |
| Timcat Ltd | Professional & scientific | 2021 |
| Time Accounts Holdings Limited | Financial services | 2022 |
| Time Accounts Investments Limited | Real estate | 2025 |
| Time Accounts Limited | Professional & scientific | 2011 |
| Timeless Toys UK Ltd | Wholesale & retail | 2018 |
| Timely Accounting Ltd | Professional & scientific | 2018 |
| Timp Limited | Information & communication | 2013 |
| Timson Capital Limited | Financial services | 2014 |
| TIN Dogs Fine Art Ltd | Manufacturing | 2013 |
| Tinku Ltd | Information & communication | 2026 |
| Tiny Medical Apps Ltd | Information & communication | 2016 |
| TIO International Limited | Wholesale & retail | 2022 |
| TIP Top Developments Limited | Real estate | 1994 |
| Tiryaq Ltd | Health & social care | 2022 |
| Tisbury Management Limited | Households | 1999 |
| Tisbury Road Limited | Households | 2013 |
| Titan Sports Limited | Wholesale & retail | 1996 |
| Titimoon Ltd | Hospitality | 2025 |
| TJM Contractors Groundworks & Plant Hire Ltd | Construction | 2021 |
| TK Electrical Services (Sussex) Ltd | Construction | 2014 |
| TL International Group Ltd | Administrative & support | 2012 |
| TL International Holdings Ltd | Financial services | 2020 |
| TLC Sales Limited | Wholesale & retail | 2023 |
| Tlcsbcompany Ltd | Construction | 2019 |
| TM Home Construction Ltd | Construction | 2021 |
| Tmac Associates Limited | Professional & scientific | 2016 |
| TN4 Associates Limited | Information & communication | 2003 |
| Toast Post Ltd | Information & communication | 2010 |
| Toastmaster DAN Limited | Professional & scientific | 2015 |
| Toat Hill Limited | Wholesale & retail | 2022 |
| Today I Should Ltd | Information & communication | 2011 |
| Together Group Ltd | Professional & scientific | 2016 |