| THE Incidental Land Company Limited | Real estate | 2010 |
| THE Intentional Network Ltd | Professional & scientific | 2018 |
| THE Italian Gardenist Ltd | Administrative & support | 2025 |
| THE Jade Vine Limited | Wholesale & retail | 2025 |
| THE Learning Corner Ltd | Education | 2024 |
| THE Lokh Group Ltd | Health & social care | 2025 |
| THE London Arts Facilitation Society CIC | Arts & recreation | 2025 |
| THE Make EM UPS Ltd | Arts & recreation | 2018 |
| THE Matriarchy Ltd | Administrative & support | 2018 |
| THE Maze Hub LLP | | 2022 |
| THE Melchemist Ltd | Health & social care | 2025 |
| THE Mind Side Ltd | Health & social care | 2025 |
| THE Monarch Partnership Ltd | Administrative & support | 2002 |
| THE NOT Terribly Well Known Company Limited | Other services | 1984 |
| THE Parent People | Education | 2025 |
| THE Plumbing Heating & GAS Consultants Ltd | Construction | 2025 |
| THE Positive Education Navigation Consultancy Ltd. | Information & communication | 2019 |
| THE Puppy Wonder Club Ltd | Other services | 2023 |
| THE Raurackl Group Limited | Information & communication | 2023 |
| THE RAY Academy of Driving Ltd | Wholesale & retail | 2019 |
| THE Recruitair Limited | Administrative & support | 2020 |
| THE Right Click (TRC) Ltd | Wholesale & retail | 2021 |
| THE ROD Limited | Health & social care | 2021 |
| THE Safer Plug Company Limited | Professional & scientific | 2024 |
| THE Tax Practice (South East) Ltd | Professional & scientific | 2004 |
| THE Tax Practice Group Ltd | Professional & scientific | 2022 |
| THE Teeth People Ltd | Manufacturing | 2017 |
| THE Training & Management Limited | Education | 2016 |
| THE Ville Global Limited | Information & communication | 2021 |
| THE Vintage Twins Ltd | Wholesale & retail | 2021 |
| THE Warehouse Dance Studios Ltd | Arts & recreation | 2024 |
| THE Weight Reversal Company Ltd | Health & social care | 2019 |
| Theeran Yash Ltd | Transport & logistics | 2022 |
| Themis International Private Court Ltd | Professional & scientific | 2021 |
| Theodoraa Ltd | Real estate | 2026 |
| Thew Arnott & Co.Limited | Wholesale & retail | 1962 |
| Think Make Consultancy Ltd | Information & communication | 2018 |
| Think Residence Ltd | Real estate | 2015 |
| Think Security Systems Limited | Construction | 2013 |
| Think Wise Properties Limited | Real estate | 2022 |
| This IZ My Story Ltd | Professional & scientific | 2021 |
| Thomas S Bullivant Ltd | Professional & scientific | 2018 |
| Three Fluffy Clouds Ltd | Wholesale & retail | 2024 |
| Three Key Designs Ltd | Professional & scientific | 2025 |
| Three Streams Psychotherapy Limited | Health & social care | 2018 |
| Threeaaait Limited | Information & communication | 2016 |
| Threekey Hub Limited | Manufacturing | 2026 |
| Through Knowledge Gain Power Ltd | Education | 2009 |
| Thurgood Design Limited | Professional & scientific | 2003 |
| Thuyan Investments Ltd | Real estate | 2018 |
| Tiempo Properties Ltd | Construction | 2026 |
| Tiger Stripes Club CIC | Health & social care | 2025 |
| Tilly's Preschool Limited | Professional & scientific | 2014 |
| TIM Deiling Lighting Design Ltd | Arts & recreation | 2024 |
| Timebarrel Limited | Administrative & support | 2016 |
| Timeland Building Services Ltd | Construction | 2016 |
| Titan Security K9 Services Limited | Administrative & support | 2025 |
| TK Properties London Ltd | Construction | 2026 |
| Tkare Limited | Health & social care | 2015 |
| TLR Dynamics Ltd | Professional & scientific | 2021 |
| TMC Invest Ltd | Financial services | 2016 |
| TN Estates Ltd | Real estate | 2020 |
| TN Food & Wine Ltd | Wholesale & retail | 2022 |
| TO the Bar Ltd | Professional & scientific | 2025 |
| Toddlertechie Ltd | Wholesale & retail | 2025 |
| TOM Brake Ltd | Professional & scientific | 2020 |
| Tomaru Solutions Ltd | Information & communication | 2015 |
| Tomroll Consultancy Limited | Professional & scientific | 2014 |
| Tons of FUN Childcare Ltd | Education | 2023 |
| Tooting & Mitcham Sports & Leisure Limited | Arts & recreation | 2000 |
| Top Closer Ltd | Professional & scientific | 2022 |
| Top Property Management Limited | Real estate | 2001 |
| Torquex Ltd | Wholesale & retail | 2023 |
| Total Design Centre Limited | Professional & scientific | 2008 |
| Total Scaffolding Solutions - London Ltd | Construction | 2025 |
| Tower of Life Ministries | Other services | 2008 |
| Toy Titan Limited | Wholesale & retail | 2025 |
| TPS UK Group Limited | Construction | 2023 |
| TPY Limited | Wholesale & retail | 2017 |
| Tracy's Style Haven Ltd | Other services | 2026 |
| Trade Club Ltd | Professional & scientific | 2026 |
| Train and Coach for People Going Places Ltd | Education | 2021 |
| Transcend Ltd | Wholesale & retail | 2017 |
| Travelbirdcars Ltd | Administrative & support | 2011 |
| Trdeals Ltd | Wholesale & retail | 2026 |
| Treasury Close (Wallington) Limited | Construction | 2014 |
| Trend World Limited | Wholesale & retail | 2018 |
| Triaxiss Infotech Limited | Information & communication | 2026 |
| Tribe Properties Global Ltd | Real estate | 2021 |
| Tribunus Holdings Limited | Financial services | 2017 |
| Trillops Limited | Information & communication | 2026 |
| Trip Electric Services Ltd | Manufacturing | 2022 |
| Tristram Group Limited | Financial services | 2025 |
| Triumph and Hope Limited | Health & social care | 2021 |
| Triumph for Life Limited | Administrative & support | 2017 |
| Trlt Property Services Limited | Real estate | 2025 |
| Troubled-Shoots Ltd | Wholesale & retail | 2024 |
| TRS Sealants Ltd | Construction | 2020 |
| Trubell Limited | Administrative & support | 1989 |
| True Care Providers Ltd | Health & social care | 2023 |