| Subprime Selections Ltd | Transport & logistics | 2024 |
| Suete Consulting Ltd | Information & communication | 2024 |
| Sugarbird Solarco (UK) Limited | Energy | 2023 |
| Suhaanya Ltd | Hospitality | 2018 |
| Sukces NA Fali Ltd | Wholesale & retail | 2023 |
| Summerfield and Lang Limited | Extraterritorial | 2001 |
| Sun 1 Food UK Ltd | Agriculture & fishing | 2018 |
| Sun Media Network Limited | Information & communication | 2025 |
| Sunbird Solar Solutions (UK) Limited | Energy | 2023 |
| Sunbird Solarco (UK) Limited | Energy | 2025 |
| Sunil Pallen Ltd | Information & communication | 2023 |
| Sunny Asset Management Limited | Financial services | 2019 |
| Sunstudio .London Limited | Construction | 2023 |
| Surgical Study Limited | Health & social care | 2020 |
| Sustainergy Ltd | Wholesale & retail | 2022 |
| Svaras Associates Ltd | Information & communication | 2019 |
| SW Commerce Group Ltd | Wholesale & retail | 2026 |
| Swan George Limited | Information & communication | 2018 |
| Swanjjd Healthcare Services Limited | Health & social care | 2023 |
| SWB Creative Limited | Professional & scientific | 2006 |
| Sweet & Scarce Ltd | Wholesale & retail | 2021 |
| Sweet Gourmet Limited | Wholesale & retail | 2025 |
| Swiss UK Property Investments Limited | Real estate | 2021 |
| Sybernautix Solutions Limited | Information & communication | 2002 |
| Sycamore Design & Build Ltd | Construction | 2024 |
| SYG Services Ltd | Administrative & support | 2016 |
| Sylnessie Company Limited | Health & social care | 2021 |
| Sylwia Klocek Accounting Ltd | Professional & scientific | 2010 |
| Syncpulse Consulting Limited | Information & communication | 2024 |
| Synthex HQ Limited | Information & communication | 2024 |
| Synverse Tech Limited | Information & communication | 2017 |
| Syon Lounge & Restaurant Ltd | Hospitality | 2024 |
| Syon Rooftop Shisha Bar Ltd | Hospitality | 2024 |
| Syon Takeaway Limited | Hospitality | 2024 |
| Syon Technology Ltd | Information & communication | 2013 |
| Sytorus (UK) Limited | Information & communication | 2018 |
| SZ Holdings Limited | Real estate | 2022 |
| T & S Accommodations Ltd | Real estate | 2024 |
| T Axiom Limited | Professional & scientific | 2015 |
| Tagore Investments Limited | Real estate | 2025 |
| Tailored Talent Limited | Professional & scientific | 2021 |
| Tale of Talents Ltd | Real estate | 2020 |
| Talento Limited | Administrative & support | 2023 |
| TAM Language Services Ltd | Professional & scientific | 2023 |
| Tamas-It Ltd. | Information & communication | 2016 |
| Tamer Consulting Ltd | Information & communication | 2013 |
| Tamogen Ltd | Professional & scientific | 2023 |
| Tanin Lettings & Investments Ltd | Real estate | 2025 |
| Targa Traders Ltd | Wholesale & retail | 2019 |
| Target Trusst Limited | Other services | 2024 |
| Targetfocus Consulting Limited | Professional & scientific | 2011 |
| Tasmax Ltd | Administrative & support | 2020 |
| Tasty Takeout Limited | Hospitality | 2023 |
| Taxbell Limited | Professional & scientific | 2012 |
| Taxsprin Financials Limited | Professional & scientific | 2014 |
| Taymouth Horsefield Ltd | Financial services | 2022 |
| Taymouth Lochen Ltd | Financial services | 2022 |
| Taymouth Trading Ltd | Financial services | 2022 |
| TC Suites Ltd | Financial services | 2023 |
| Tcherno Limited | Wholesale & retail | 2018 |
| TCS Express Worldwide (UK) Limited | Transport & logistics | 2003 |
| Tea Time Cafe Ltd | Hospitality | 2024 |
| Teafields Ltd | Hospitality | 2012 |
| Team Normandy Limited | Wholesale & retail | 2017 |
| Teardusk Limited | Arts & recreation | 2014 |
| Tech 23 Ltd | Manufacturing | 2019 |
| Tech Farm Limited | Information & communication | 2019 |
| Tech Go Ltd | Wholesale & retail | 2023 |
| Technet Cloud Solutions Limited | Information & communication | 2018 |
| Technique Graphic Limited | Professional & scientific | 2000 |
| Techstream IT Services Limited | Information & communication | 2024 |
| Teenbridge C.I.C. | Education | 2025 |
| Tehran Services Ltd | Other services | 2018 |
| Telar Limited | Construction | 2016 |
| Telly Limited | Information & communication | 2019 |
| Temida London Limited | Professional & scientific | 2013 |
| Tempion Ltd | Information & communication | 2010 |
| TEN Parts Ltd | Administrative & support | 2025 |
| Tenet Enterprise Ltd | Other services | 2021 |
| Teros Technology Ltd | Information & communication | 2026 |
| Terra Astra Limited | Wholesale & retail | 2026 |
| Tescreative Ltd | Administrative & support | 2013 |
| Tesoro London Limited | Wholesale & retail | 2021 |
| Tessarine Ltd | Information & communication | 2022 |
| Teuk Limited | Manufacturing | 2005 |
| Texamine Limited | Information & communication | 2021 |
| TGY Group LP | | 2019 |
| Thai Staff Training Ltd | Education | 2017 |
| Thamel Consulting Ltd | Professional & scientific | 2025 |
| Thames ROW RTM Company Limited | Households | 2012 |
| Thames Tidal Engineering Ltd | Manufacturing | 2026 |
| Thamson Healthcare Limited | Wholesale & retail | 2021 |
| THE Ability Group Limited | Professional & scientific | 2004 |
| THE Academy Player Ltd | Extraterritorial | 2021 |
| THE Aimita Corporation Limited | Extraterritorial | 2008 |
| THE Amber Centre Ltd | Wholesale & retail | 1994 |
| THE Animation Station London Limited | Professional & scientific | 2014 |
| THE Asklepaedia Limited | Health & social care | 2008 |
| THE Bentley Sterling Group Limited | Professional & scientific | 2017 |
| THE Body Makiwara Company Ltd | Extraterritorial | 2025 |