| Tilkey Garden Services Ltd | Administrative & support | 2021 |
| Timtech Ltd | Professional & scientific | 2010 |
| Tiny Trunks Limited | Wholesale & retail | 2020 |
| Tiptree Precision Engineering Limited | Professional & scientific | 2006 |
| Tiptree Properties Ltd | Real estate | 2020 |
| Titan Foundations Limited | Construction | 1988 |
| TJS Contracting Ltd | Construction | 2025 |
| Tkpc Limited | Information & communication | 2012 |
| TLC Party Services Ltd | Hospitality | 2024 |
| TLT Fitness Ltd | Other services | 2021 |
| TLT UK Property Limited | Hospitality | 2012 |
| TM & KM Holdings Ltd | Other services | 2024 |
| TM Marina LLP | | 2008 |
| TMA Decorating Limited | Construction | 2022 |
| TMA Sales Limited | Wholesale & retail | 2022 |
| TMT Training Services Limited | Construction | 2015 |
| TNM Estate Solutions Limited | Water & waste | 2025 |
| TNM Investments Limited | Real estate | 2025 |
| Toes 'N' Tots Nursery Limited | Education | 2026 |
| Tollesbury Boiler Service Limited | Construction | 2002 |
| Tollesbury Cruising Club Limited | Administrative & support | 2006 |
| Tollesbury Cuisine Ltd. | Hospitality | 2016 |
| Tollesbury Maritime Heritage Community Interest Company | Manufacturing | 2022 |
| Tollesbury Pre-School Community Interest Company | Education | 2008 |
| Tollesbury Television Service Limited | Wholesale & retail | 1966 |
| Tolleshunt D'Arcy Pre-School | Education | 2011 |
| Tolleshunt Major Holdings Ltd | Financial services | 2026 |
| TOM Green Physiotherapy Ltd | Health & social care | 2022 |
| TOM Keane's Antique Traders Limited | Wholesale & retail | 2014 |
| Tommy Butler Ltd. | Administrative & support | 2021 |
| Tomova Consultancy Ltd | Information & communication | 2022 |
| Tone Limited | Administrative & support | 2000 |
| Top Taps (UK) Limited | Wholesale & retail | 2013 |
| Topsail Charters Limited | Arts & recreation | 1999 |
| Toptree (2015) Limited | Real estate | 2015 |
| Torque Monkey Automotive Ltd | Wholesale & retail | 2023 |
| Torque Monkey Holdings Limited | Real estate | 2023 |
| Torque Monkey Limited | Manufacturing | 2020 |
| Torque Monkey Performance Limited | Wholesale & retail | 2020 |
| Totality Systems Limited | Information & communication | 2010 |
| Totham Community Store Ltd | Wholesale & retail | 2026 |
| Totham Homes Ltd | Construction | 2023 |
| Toyama KOI Company Limited | Wholesale & retail | 1998 |
| TPL Warehousing Limited | Transport & logistics | 2004 |
| Trade Price Cars (Essex) Limited | Wholesale & retail | 2012 |
| Trade Price Vans Ltd | Wholesale & retail | 2023 |
| Trade Wind Technology Ltd | Information & communication | 1998 |
| Tradeteam Construction Limited | Construction | 2025 |
| Traer Clark Architect Limited | Professional & scientific | 2007 |
| Traer Clark Investment Management Ltd | Professional & scientific | 2009 |
| Traer Clark Limited | Professional & scientific | 1991 |
| Trait Design Limited | Administrative & support | 2002 |
| Tranquillity E3/15 Limited | Real estate | 2025 |
| Tranquillity E3/16 Limited | Real estate | 2025 |
| Tranquillity E3/17 Limited | Real estate | 2025 |
| Tranquillity E4/15 Limited | Real estate | 2025 |
| Tranquillity E4/16 Limited | Real estate | 2025 |
| Tranquillity E4/17 Limited | Real estate | 2025 |
| Transport of Essex Ltd | Transport & logistics | 2022 |
| Trattoria Italiana 2026 Ltd | Hospitality | 2025 |
| Travel Systems (UK) Limited | Extraterritorial | 1996 |
| Treadlarge Limited | Wholesale & retail | 1986 |
| Trenfield Croft Limited | Professional & scientific | 2016 |
| Triangle Place (Maldon) Management Company Limited | Households | 2012 |
| Tripartite Ltd | Information & communication | 2026 |
| Triumph Scaffolding Ltd | Construction | 2026 |
| Tropical Heat & Plumbing Limited | Construction | 2014 |
| Tropical Traders Ltd | Wholesale & retail | 2021 |
| Tru-Size Ltd | Professional & scientific | 2023 |
| True Classic Tattoo Ltd | Arts & recreation | 2024 |
| TS Construction Renovator Ltd | Construction | 2024 |
| TS Rigging & Marine Services Ltd | Manufacturing | 2022 |
| TS Rigging - Tall Ships Limited | Manufacturing | 2022 |
| TS Rigging Limited | Administrative & support | 2002 |
| TSI Global Ltd | Professional & scientific | 2005 |
| TSJ Eastways Ltd | Information & communication | 2015 |
| TT Company Services Ltd | Other services | 2015 |
| Ttrs Limited | Professional & scientific | 2008 |
| Turner Electrical Essex Ltd | Construction | 2020 |
| Twisted Automation Limited | Manufacturing | 2016 |
| TY KAR Limited | Administrative & support | 2014 |
| Tyler & Haden Holdings Ltd | Financial services | 2025 |
| Tyndale Terrace Limited | Construction | 2014 |
| Tyre Safe Limited | Wholesale & retail | 2017 |
| UCL Construction Ltd | Construction | 2024 |
| UCL Group Development Ltd | Real estate | 2021 |
| UK Animal Products Limited | Manufacturing | 1999 |
| UK Assets Group Holdings Ltd | Administrative & support | 2019 |
| UK Deed Poll Service Limited | Other services | 2013 |
| UK Maldon Ltd | Other services | 2018 |
| Unipro Projects Limited | Real estate | 2013 |
| Unique Assessments Ltd | Health & social care | 2023 |
| Unique Health and Fitness Studio Limited | Arts & recreation | 2015 |
| Unite Electrical Solutions Ltd | Construction | 2013 |
| United Highways Limited | Construction | 2024 |
| Unitro Chemical Group Ltd | Administrative & support | 2022 |
| Unity in Community Limited | Extraterritorial | 2021 |
| Universal Risk Limited | Administrative & support | 2023 |
| Universal Services (Sports Equipment) Limited | Manufacturing | 2005 |
| Unreelated Media Limited | Real estate | 2021 |