| Studio Finance Partners Limited | Professional & scientific | 2026 |
| Studio Garella Limited | Professional & scientific | 2014 |
| Studio ZER Limited | Professional & scientific | 2025 |
| Style Build Construction Ltd | Construction | 2026 |
| Stylecreep Limited | Wholesale & retail | 2012 |
| Stylehairo Ltd | Wholesale & retail | 2022 |
| Stylist CUT Co Ltd | Other services | 2023 |
| Stylus Networks Limited | Wholesale & retail | 2018 |
| SU Motors Ltd | Wholesale & retail | 2024 |
| Substrate Autonomous Ltd | Information & communication | 2018 |
| Subtropic BDA Limited | Manufacturing | 2018 |
| Subzeewala Limited | Wholesale & retail | 2025 |
| Sucara Developments Ltd | Real estate | 2025 |
| Succurro Consulting Limited | Financial services | 2013 |
| Sufi Saints Music Limited | Information & communication | 2026 |
| Sun Engineering Group Ltd | Construction | 2021 |
| Sunbeam Spares Company Limited | Wholesale & retail | 2012 |
| Sunfly Karaoke Limited | Information & communication | 2003 |
| Sunfly Music Group Limited | Arts & recreation | 2005 |
| Sunshine Prodco Ltd | Information & communication | 2025 |
| Sunshine Studios Motion Limited | Information & communication | 2026 |
| Superior Plumbing Limited | Construction | 2024 |
| Supply Nest Commerce Ltd | Wholesale & retail | 2026 |
| Supportpal Limited | Information & communication | 2016 |
| Supravari Ltd | Real estate | 2021 |
| Sura Heating and Plumbing Ltd | Construction | 2021 |
| Surgery Fellows Ltd | Education | 2022 |
| Surgery for Children London Private Limited | Health & social care | 2018 |
| Surrey Inventory Services Limited | Households | 2016 |
| Sutton 81 Ltd | Real estate | 2021 |
| SV Plumbing Limited | Construction | 2016 |
| Svasti Consulting Ltd | Professional & scientific | 2025 |
| Sveze Limited | Wholesale & retail | 2014 |
| SVK Consultancy Limited | Health & social care | 2022 |
| SW Imperial Limited | Professional & scientific | 2025 |
| SW Utility Solutions Ltd | Professional & scientific | 2023 |
| Swaad by Patel Ltd | Hospitality | 2025 |
| Swanston Consulting Limited | Professional & scientific | 2010 |
| Sweet Beams Ltd | Wholesale & retail | 2022 |
| Sweet Care Agency Ltd | Health & social care | 2025 |
| Sweet Cuddles Nursery Ltd | Health & social care | 2023 |
| Sweet Key Ltd | Real estate | 2025 |
| Swift Safe Secure Ltd | Transport & logistics | 2025 |
| Swifterio Limited | Information & communication | 2022 |
| Swimming With Style Limited | Arts & recreation | 2009 |
| Swimmore Limited | Other services | 2017 |
| Swingfest Limited | Arts & recreation | 2015 |
| Swingland Limited | Arts & recreation | 1999 |
| Swiss Freight Limited | Transport & logistics | 2006 |
| Syas Financial Services Ltd | Financial services | 2012 |
| Syas Properties Limited | Real estate | 2021 |
| Syed Holdings Ltd | Real estate | 2022 |
| Synet Limited | Professional & scientific | 2012 |
| Syntx Limited | Information & communication | 2026 |
| Syon Cleaning Ltd | Administrative & support | 2026 |
| Syon Food & Wine Ltd | Wholesale & retail | 2019 |
| Syon Hair Limited | Other services | 2025 |
| Syon Oak Ltd | Real estate | 2020 |
| Syon Real Estates Limited | Real estate | 2024 |
| System Controls (Ventilation) Limited | | 1985 |
| SZN FC Ltd | Arts & recreation | 2025 |
| T and J Import Company Limited | Wholesale & retail | 2004 |
| T D Footsteps Ltd | Real estate | 2015 |
| T S Design (EU) Limited | Arts & recreation | 2006 |
| T&M Enterprises London Ltd | Real estate | 2026 |
| T&Z Cleaning and Painting-Decorating Company Ltd | Administrative & support | 2013 |
| T-Connect Ltd | Wholesale & retail | 2020 |
| T.A.S.S Electrical & Plumbing Ltd | Construction | 2011 |
| T5 Hotel Management Ltd | Hospitality | 2022 |
| T5 Operating Company Limited | Hospitality | 2022 |
| Taaj Design and Build Ltd | Construction | 2021 |
| Tableized Limited | Information & communication | 2020 |
| Tabletop Holdings Ltd | Hospitality | 2025 |
| Tachbrook Builders Limited | Construction | 2016 |
| Tailormade Gymnasts Ltd | Education | 2024 |
| Take a Look Shop Ltd | Wholesale & retail | 2024 |
| Takeway Bakery Limited | Hospitality | 2026 |
| Takht Enterprise Limited | Real estate | 2023 |
| Taksh Realty Ltd | Real estate | 2025 |
| Takta Ltd | Financial services | 2018 |
| Talent Data Supply Ltd | Administrative & support | 2025 |
| Talentsignals Ltd | Information & communication | 2026 |
| Talha Enterprises Private Limited | Transport & logistics | 2025 |
| Talhi's Creation Ltd | Wholesale & retail | 2020 |
| Talking Toolbox Limited | Information & communication | 2009 |
| Talyá Skin and Science Ltd | Health & social care | 2026 |
| Tandoori Feast Ltd | Hospitality | 2025 |
| Tangramarket Limited | Construction | 2007 |
| Tani Cleaning Services Ltd | Administrative & support | 2025 |
| Tanima Estates Ltd | Real estate | 2019 |
| Tarly International UK Limited | Wholesale & retail | 2022 |
| Task Cellular Ltd | Information & communication | 2007 |
| Taveira Limited | Hospitality | 2015 |
| Taxallay Ltd | Professional & scientific | 2024 |
| Taxiform Limited | Professional & scientific | 2026 |
| Taylor Wellbeing Limited | Health & social care | 2025 |
| Tayyab Tahir Trader Ltd | Wholesale & retail | 2025 |
| TBA Site Services Ltd | Construction | 2023 |
| Techdata Systems Limited | Information & communication | 2024 |
| Technests Limited | Professional & scientific | 2016 |