| TAB Group Holdings Ltd | Financial services | 2024 |
| TAI Group Limited | Information & communication | 2025 |
| Tailored Journeys Ltd | Administrative & support | 2017 |
| Tailored Performance Personal Training Ltd | Arts & recreation | 2026 |
| Tailoreducation Recruitment Ltd | Administrative & support | 2025 |
| Take on Ltd | Information & communication | 2025 |
| Talac Solutions Ltd | Professional & scientific | 2025 |
| Tall Oak Properties Ltd | Construction | 2018 |
| Talon Global Limited | Administrative & support | 2023 |
| Tapli Technology Ltd | Wholesale & retail | 2014 |
| Taurus Contracting Group Limited | Administrative & support | 2019 |
| Taylor & Gillard Tools Limited | Administrative & support | 2001 |
| Tbbl Ltd | Financial services | 2010 |
| TBC Consulting Ltd | Professional & scientific | 2017 |
| TBL Systems Limited | Information & communication | 2007 |
| TDL Recruitment Ltd | Transport & logistics | 2015 |
| Team Liberty Ltd | Administrative & support | 2017 |
| Team Publishing Limited | Information & communication | 2005 |
| Technical Electrical Services Limited | Construction | 1995 |
| Telos Impact Ltd | Financial services | 2026 |
| Tempeo Construction Solutions Limited | Administrative & support | 2026 |
| Tempeo Payroll Limited | Administrative & support | 2026 |
| TEN2TWO Limited | Administrative & support | 2002 |
| Tenelume Ltd | Professional & scientific | 2022 |
| Tenzing Scaffolding Ltd | Construction | 2023 |
| Terraced Ltd | Information & communication | 2026 |
| TES Payroll Limited | Administrative & support | 2026 |
| Tessa Davidson Limited | Professional & scientific | 2005 |
| Tfconnect EOT Ltd | Other services | 2025 |
| Tfconnect Global Talent & Partnerships Ltd | Administrative & support | 2021 |
| Tfconnect Ltd. | Real estate | 2008 |
| Thai Design Distributors Limited | Wholesale & retail | 1975 |
| Thames and Medway Canal Association Limited | Arts & recreation | 2005 |
| THE 35 Foot Limited | Information & communication | 2026 |
| THE Abbeyfield (Berkhamsted and Hemel Hempstead) Society Limited | Hospitality | 1969 |
| THE AC Electricians Ltd | Manufacturing | 2025 |
| THE Afferentology Association Ltd | Professional & scientific | 2016 |
| THE Art & Hobby Shop Limited | Professional & scientific | 1997 |
| THE Art Shed CIC | Arts & recreation | 2026 |
| THE Avenue London Ltd | Other services | 2020 |
| THE Beeches (Thurleigh) Limited | Construction | 2025 |
| THE Beeches Thurleigh Management Company 2 Limited | Households | 2024 |
| THE Bradfield Balance Ltd | Health & social care | 2026 |
| THE Brownlow Gate Management Company Limited | Administrative & support | 2000 |
| THE Bull Berko Ltd | Hospitality | 2023 |
| THE Business Side Limited | Professional & scientific | 2016 |
| THE Business Train Ltd | Professional & scientific | 2017 |
| THE Car Works (Herts) Ltd | Wholesale & retail | 2016 |
| THE Cheese and Deli Company Ltd | Wholesale & retail | 2026 |
| THE Cherry Perry PUB Co Ltd | Hospitality | 2024 |
| THE Clothing Line Limited | Wholesale & retail | 2002 |
| THE Confidence Psychologist Ltd | Education | 2022 |
| THE Courtyards Tring Limited | Households | 2020 |
| THE Dacorum Heritage Trust Limited | Arts & recreation | 1993 |
| THE Design Department Ltd | Information & communication | 2011 |
| THE Diamond Trust Trading Company Limited | Administrative & support | 1997 |
| THE Dogtographer Ltd | Professional & scientific | 2026 |
| THE Downsize Partners Limited | Administrative & support | 2025 |
| THE Draft$ Ltd | Wholesale & retail | 2025 |
| THE Employment Management Platform Ltd | Administrative & support | 2017 |
| THE Feldenkrais Guild UK Limited | Professional & scientific | 1994 |
| THE GAP Partnership Bidco Limited | Professional & scientific | 2016 |
| THE GAP Partnership Group Limited | Professional & scientific | 2016 |
| THE GAP Partnership Holdings Limited | Professional & scientific | 2011 |
| THE GAP Partnership Limited | Professional & scientific | 1997 |
| THE Garden Collective Ltd | Administrative & support | 2024 |
| THE Gatehill Property Company Limited | Construction | 1995 |
| THE Golf HUT Ltd | Arts & recreation | 2015 |
| THE Grafter AI Ltd | Information & communication | 2026 |
| THE Harper Collection Ltd | Wholesale & retail | 2014 |
| THE Hertfordshire Garden Centre Limited | Wholesale & retail | 2009 |
| THE Hive MGT Limited | Real estate | 2026 |
| THE Home ED Hangout Community Interest Company | Education | 2025 |
| THE Homes Doctor Ltd | Real estate | 2023 |
| THE House of Pink Limited | Arts & recreation | 2017 |
| THE Human Talent Project Ltd | Administrative & support | 2023 |
| THE Imperial Crown Hotel Limited | Hospitality | 1996 |
| THE Jigsaw Bar Company Ltd | Hospitality | 2015 |
| THE Keep Curations Limited | Wholesale & retail | 2025 |
| THE Laurels Estates (Potten END) Limited | Real estate | 1990 |
| THE Legal Secretary (London) Limited | Administrative & support | 2022 |
| THE Liberty Corporation Limited | Construction | 2007 |
| THE Lightbulb Tree Limited | Administrative & support | 2016 |
| THE Lotus Psychology Practice Ltd | Health & social care | 2022 |
| THE Mindset Development Group Ltd | Professional & scientific | 2012 |
| THE Mortgage Market (England) Limited | Financial services | 2015 |
| THE Noble Grape Limited | Wholesale & retail | 2005 |
| THE Old Berkhamstedians Limited | Other services | 2009 |
| THE Online Events Company Limited | Arts & recreation | 2022 |
| THE Osteo Practice Limited | Other services | 2017 |
| THE Packing Room @ Warehouse Pizza Limited | Hospitality | 2021 |
| THE Payments Expert Ltd | Information & communication | 2023 |
| THE Pines (Berkhamsted) Maisonette Management Limited | Real estate | 2015 |
| THE Pines (Berkhamsted) Management Company Limited | Real estate | 2015 |
| THE Planning Review Limited | Information & communication | 2025 |
| THE Plough Potten END Limited | Hospitality | 2010 |
| THE Positive Method Ltd | Health & social care | 2021 |
| THE Recruitment FIX Limited | Administrative & support | 2011 |
| THE Regency Hotel Hospitality Limited | Hospitality | 2019 |
| THE Rental Income Consultancy Ltd | Other services | 2013 |