| Team Technologies Limited | Information & communication | 1992 |
| Tech Accessories Ltd | Wholesale & retail | 2018 |
| TECH11 Limited | Wholesale & retail | 2018 |
| Techmait Technologies Ltd | Information & communication | 2024 |
| Technical Services Design Consultancy Limited | Professional & scientific | 2008 |
| Technical Services Refrigeration & Air Conditioning Ltd | Construction | 1992 |
| Technological Business Solutions Limited | Information & communication | 1994 |
| Technoxium Ltd | Information & communication | 2026 |
| Techpulse Group Limited | Information & communication | 2016 |
| Techterm Solutions Limited | Information & communication | 2021 |
| Teec Limited | Information & communication | 2005 |
| Telcoit Solutions Ltd | Information & communication | 2019 |
| Telint Limited | Professional & scientific | 2012 |
| Temeraire London Limited | Information & communication | 2011 |
| Temeraire Ventures Limited | Professional & scientific | 2014 |
| TEN 19 Limited | Professional & scientific | 2013 |
| Tequedough Factory Ltd | Manufacturing | 2022 |
| Terrasync Solutions Limited | Information & communication | 2025 |
| Test Technologies Holdings Limited | Administrative & support | 2008 |
| Test Valley Kitchens & Bathrooms Ltd | Construction | 2021 |
| TEST4LESS Ltd. | Extraterritorial | 2001 |
| Tetravp Ltd | Professional & scientific | 2023 |
| TFS Consultancy Limited | Professional & scientific | 2023 |
| Tgif Business Solutions Limited | Information & communication | 2019 |
| Thames Vale Investments Limited | Real estate | 2001 |
| Thames Vale Properties Limited | Real estate | 1988 |
| Thames Valley Estimating Limited | Professional & scientific | 2005 |
| Thames Valley Plumbing & Heating Ltd | Construction | 2019 |
| Thames Valley Surveying Limited | Professional & scientific | 2013 |
| Thamesy Ltd | Wholesale & retail | 2026 |
| That Handy Bloke Ltd | Construction | 2025 |
| That Handy Bloke Projects Ltd | Construction | 2025 |
| Thatcham Butchers Limited | Wholesale & retail | 2011 |
| Thatcham MOT & Service Centre Limited | Wholesale & retail | 2012 |
| Thatcham Tyre & Exhaust Centre Limited | Wholesale & retail | 2007 |
| THE Alinea Collective Ltd | Hospitality | 2020 |
| THE Auction Buyer Ltd | Other services | 2018 |
| THE Auto Mover (South) Ltd | Wholesale & retail | 2021 |
| THE Bear Club Collective Ltd | Administrative & support | 2026 |
| THE Beekeeper’S Daughter Limited | Wholesale & retail | 2025 |
| THE Bevy Management Company Limited | Administrative & support | 2018 |
| THE Bicester Shutter Company Limited | Manufacturing | 2014 |
| THE Big 6 Flyers Limited | Transport & logistics | 2013 |
| THE Bike Whisperer Ltd | Other services | 2007 |
| THE Blockhouse Technology Limited | Information & communication | 2018 |
| THE Blue Cafe Travel Company Ltd | Information & communication | 2017 |
| THE Bridal Dress Company Ltd | Wholesale & retail | 2021 |
| THE British Institute of Hypnotherapy & NLP Limited | Other services | 2015 |
| THE Brunch Haus Limited | Hospitality | 2025 |
| THE Business Bible Group Ltd | Information & communication | 2017 |
| THE Business Developers Ltd | Information & communication | 2026 |
| THE Buyers Buddy Limited | Administrative & support | 2009 |
| THE Cabbage Patch Cheveley Development Company Limited | Construction | 2023 |
| THE Cellar Community Ltd | Wholesale & retail | 2026 |
| THE Chantry Management Company (Newbury) Limited | Households | 2002 |
| THE Charlie Waller Trust | Health & social care | 2005 |
| THE Clay Company UK Limited | Wholesale & retail | 2003 |
| THE Clockmaker Limited | Other services | 2014 |
| THE Clothing Warehouse Limited | Wholesale & retail | 2016 |
| THE Clubhouse Indoor Play Ltd | Arts & recreation | 2026 |
| THE Coach People Limited | Administrative & support | 2013 |
| THE Coach Travel Group Limited | Other services | 2024 |
| THE Comedy Development Company Ltd | Information & communication | 2016 |
| THE Common Good Network Ltd | Professional & scientific | 2025 |
| THE Compton Swan Ltd | Hospitality | 2010 |
| THE Conference Shop Limited | Administrative & support | 1990 |
| THE Consultarium Ltd | Professional & scientific | 2011 |
| THE Content Candy Store Ltd | Information & communication | 2020 |
| THE Core (Swindon) Ltd | Hospitality | 2012 |
| THE County Rooms Group Limited | Real estate | 2006 |
| THE Crown KC Ltd | Hospitality | 2025 |
| THE Demand Team Limited | Information & communication | 2025 |
| THE DEW Pond (Old Burghclere) Ltd | Hospitality | 2022 |
| THE Drake I Limited Liability Partnership | | 2013 |
| THE Dyson Project Ltd | Professional & scientific | 2016 |
| THE Electrical Crew Limited | Extraterritorial | 2013 |
| THE Emea Enterprise Company Limited | Information & communication | 2001 |
| THE Event Horse Owners Association Limited | Arts & recreation | 2002 |
| THE Expert Publishing Group Ltd | Information & communication | 2023 |
| THE First Lensman Limited | Wholesale & retail | 2024 |
| THE Fives Court Company Ltd | Administrative & support | 2009 |
| THE Flourishing Group Limited | Administrative & support | 2024 |
| THE Forest Edge Residents Management Company Limited | Households | 2008 |
| THE Fork Lift Truck Association Limited | Other services | 1972 |
| THE Fork Truck Hire Association Ltd | Other services | 1994 |
| THE Friendly OIL Boiler Service Ltd | Administrative & support | 2014 |
| THE Garden Design Company Limited | Administrative & support | 1996 |
| THE General Services Association | Other services | 2006 |
| THE Gentleman Smoker Limited | Hospitality | 2021 |
| THE Godman Charitable Company Limited | Health & social care | 1977 |
| THE Good Ideas Factory Limited | Information & communication | 2011 |
| THE Good Money Coach Limited | Financial services | 2021 |
| THE Good Money Group Limited | Education | 2021 |
| THE Grain Loft Limited | Real estate | 2019 |
| THE Graphic Studio Limited | | 1988 |
| THE Great British Coach Company Limited | Transport & logistics | 2020 |
| THE Green Shed Cider Company Limited | Manufacturing | 2018 |
| THE Groves (Newbury) Management Company Limited | Households | 2015 |
| THE GUN Restaurant Ltd | Hospitality | 2016 |
| THE Hair & Beauty Barn Limited | Other services | 2015 |