| TG Lucrum Ltd | Real estate | 2023 |
| TG Tech Ltd | Information & communication | 2025 |
| TGH Carpentry Ltd | Construction | 2026 |
| TGN Health Ltd | Health & social care | 2022 |
| TGS Learning UK Ltd | Professional & scientific | 2024 |
| TGW Group Ltd | Transport & logistics | 2026 |
| TH Action Design Limited | Arts & recreation | 2022 |
| TH Snug Property Ltd | Real estate | 2025 |
| Thackray Mantle Consultants Ltd | Professional & scientific | 2022 |
| Thai Global Food Store Limited | Wholesale & retail | 2014 |
| Thai Harmony MK Ltd | Other services | 2024 |
| Thai on the River LLP | | 2009 |
| Thakkar Investments Ltd | Real estate | 2021 |
| Thalorix Group Ltd | Administrative & support | 2026 |
| Thame Joinery Company Limited | Manufacturing | 1972 |
| Thamek Ltd | Financial services | 2014 |
| Thames Cash & Carry Limited | Wholesale & retail | 1983 |
| Thames United Verifications and Inspections Ltd | Construction | 2023 |
| Thames View Store Ltd | Wholesale & retail | 2025 |
| Thamesbridge College Ltd | Education | 2025 |
| Thamothi Ltd | Wholesale & retail | 2025 |
| Thao Limited | Other services | 2018 |
| Thapsus MK Ltd | Hospitality | 2024 |
| Thara Fleet Solutions Limited | Administrative & support | 2025 |
| Thara Housing Ltd | Real estate | 2022 |
| Tharaaedu Limited | Information & communication | 2023 |
| Tharam Tech Testing Ltd | Information & communication | 2025 |
| Tharsan-Niro Ltd | Transport & logistics | 2019 |
| That Cleaning Company Milton Keynes Ltd | Administrative & support | 2026 |
| That Counselling Place Ltd | Hospitality | 2024 |
| That Stuff Ltd | Wholesale & retail | 2026 |
| That's Going in My Basket Limited | Wholesale & retail | 2023 |
| Thaxcorp Education and Training Ltd | Education | 2026 |
| Thaxia Medical Ltd | Professional & scientific | 2026 |
| THB Homes Ltd | Construction | 2003 |
| Thcb Consult Ltd | Professional & scientific | 2021 |
| Thdp Limited | Health & social care | 2024 |
| THE 3 Big B'S Ltd | Hospitality | 2025 |
| THE 48 Warrior Square RTM Company Ltd | Real estate | 2006 |
| THE 777 Marketing Group Ltd | Information & communication | 2025 |
| THE ABR Company Limited | Administrative & support | 1993 |
| THE Accountant London Limited | Professional & scientific | 2025 |
| THE Acorns Freehold Company Limited | Households | 2002 |
| THE Acres Estate Management Company Limited | Real estate | 2024 |
| THE Activity Haven Ltd | Hospitality | 2024 |
| THE Address Hotels Limited | Information & communication | 2008 |
| THE Adjei Ltd | Hospitality | 2025 |
| THE Admin Hub MK Ltd | Administrative & support | 2026 |
| THE Advertising Archive Ltd. | Arts & recreation | 1988 |
| THE Aesthetics Clinic Swanland Ltd | Other services | 2022 |
| THE Aesthetics Doctor by Doctor Ahmed Ltd | Health & social care | 2023 |
| THE African Housing Company Ltd | Real estate | 2012 |
| THE African POT Ltd | Hospitality | 2024 |
| THE Agency Collective Ltd | Other services | 2013 |
| THE Agyeman Services Ltd | Information & communication | 2018 |
| THE AJR Partnership Ltd | Administrative & support | 2010 |
| THE AJR Partnership Property Ltd | Real estate | 2017 |
| THE Alliance Schools Trust | Education | 2011 |
| THE Alpha Healthcare Consultancy Limited | Professional & scientific | 1995 |
| THE Apostolic Faith Mission of Africa in UK Limited | Other services | 2025 |
| THE Appbooth Limited | Other services | 2017 |
| THE Arbor-Barber Ltd | Agriculture & fishing | 2021 |
| THE Archive Vintage Clothing Company Ltd | Wholesale & retail | 2026 |
| THE Arló Nail Collection Ltd | Wholesale & retail | 2019 |
| THE Association of Open University Graduates | Other services | 1999 |
| THE Astral Forest Ltd | Construction | 2024 |
| THE Aurelius Foundation Community Interest Company | Education | 2019 |
| THE Automation Studio Limited | Information & communication | 2026 |
| THE Axclub Limited | Arts & recreation | 2026 |
| THE Bakery Group Ltd | Manufacturing | 2023 |
| THE Balloon Boutique MK Ltd | Wholesale & retail | 2021 |
| THE Balloon Loft Warehouse Ltd | Wholesale & retail | 2025 |
| THE Barbers Lounge MK Ltd | Other services | 2023 |
| THE Bardon Group (Holdings) Limited | Professional & scientific | 2024 |
| THE Bardon Group Limited | Professional & scientific | 1997 |
| THE Bargroffee Coffee Shop Ltd | Hospitality | 2025 |
| THE Barley Thorpe Hesley Ltd | Hospitality | 2022 |
| THE Barn Recovery Ltd | Health & social care | 2026 |
| THE Bathing Machine Limited | Wholesale & retail | 2003 |
| THE Baze Restaurant Limited | Hospitality | 2017 |
| THE Beaufort Group of Companies Limited | Financial services | 2012 |
| THE Beauty Creative Limited | Professional & scientific | 2019 |
| THE Bedford Corporation Ltd | Real estate | 2026 |
| THE Beehive at Deanshanger Ltd | Hospitality | 2023 |
| THE Bestie London Ltd | Wholesale & retail | 2020 |
| THE Bestway Digital Ltd | Information & communication | 2026 |
| THE Beulah Rose Group Ltd | Arts & recreation | 2026 |
| THE BID Writer Limited | Wholesale & retail | 2002 |
| THE Big BAD Wolf Entertainment Company Limited | Information & communication | 2026 |
| THE Big Bird Film Company Limited | Arts & recreation | 1994 |
| THE Big Flavour Co Limited | Manufacturing | 2020 |
| THE Biofactory Ltd | Professional & scientific | 2018 |
| THE Birch and Beyond Ltd | Hospitality | 2025 |
| THE Birth Project Ltd | Education | 2023 |
| THE Black Box MK Ltd | Hospitality | 2025 |
| THE Black Sheep Collective CIC | Education | 2013 |
| THE Bletchley Transformation Academy Limited | Professional & scientific | 2026 |
| THE Blind MAN MK Ltd | Wholesale & retail | 2016 |
| THE Blinds Portal UK Ltd | Wholesale & retail | 2023 |
| THE Blue Group (Restaurants) Ltd | Hospitality | 2014 |