| SWS Electrical Solutions Ltd | Construction | 2020 |
| SWS Financial Services Ltd | Financial services | 2020 |
| SY Meded Limited | Health & social care | 2024 |
| Syam Construction Ltd | Construction | 2021 |
| Sycamore Tree Investments Ltd | Real estate | 2019 |
| SYD Tech Limited | Administrative & support | 2017 |
| SYD Wholesale Limited | Wholesale & retail | 2025 |
| Sydswift Ltd | Wholesale & retail | 2010 |
| Syedain Financial Associates Limited | Financial services | 2005 |
| Sygix Limited | Administrative & support | 2019 |
| Syle Transport Ltd | Transport & logistics | 2025 |
| Syllabuswiz Ltd | Information & communication | 2026 |
| Sylo Events Limited | Arts & recreation | 2022 |
| Sylvic Limited | Professional & scientific | 1996 |
| Sylvie Services Ltd | Administrative & support | 2021 |
| Sylvin Publishing Ltd | Information & communication | 2024 |
| Symbiotix Ltd | Information & communication | 2022 |
| Symom Limited | Wholesale & retail | 2017 |
| Symonn Design Ltd | Manufacturing | 2019 |
| Symphonies Club Limited | Hospitality | 1996 |
| Symposia Theatres Limited | Arts & recreation | 2023 |
| SYN Planet Ltd | Wholesale & retail | 2024 |
| Sync Developments Ltd | Construction | 2023 |
| Sync Ledger Tech Limited | Households | 2024 |
| Sync Logistics Ltd | Transport & logistics | 2025 |
| Synergy Holding Group Ltd | Financial services | 2024 |
| Synergy IT Service Limited | Other services | 2012 |
| Synergy Lifestyle Limited | Real estate | 2006 |
| Synergy Locum Services Limited | Wholesale & retail | 2011 |
| Synergy MMS Limited | Professional & scientific | 2008 |
| Synergy Nutrition and Fitness Ltd | Other services | 2020 |
| Synergy Transformation Ltd | Information & communication | 2020 |
| Synergyb Ltd | Professional & scientific | 2014 |
| Synetics Global Security Ltd | Administrative & support | 2011 |
| Syntaxone Limited | Information & communication | 2009 |
| Syntec MLD Ltd | Other services | 2022 |
| Syntiga Limited | Administrative & support | 2002 |
| Syntropic Limited | Professional & scientific | 2013 |
| Syon Hotels Limited | Construction | 2014 |
| Syrinity Capital Ltd | Real estate | 2014 |
| Syro Grup Limited | Wholesale & retail | 2019 |
| Sysecture Ltd | Information & communication | 2016 |
| Sysinfo Solutions Limited | Information & communication | 2016 |
| Systech Industries Limited | Wholesale & retail | 2004 |
| Systematic Manufacturing Limited | Wholesale & retail | 2015 |
| Systems HK Limited | Real estate | 2023 |
| Syster Properties Ltd | Hospitality | 2019 |
| Systime Health Ltd | Professional & scientific | 2019 |
| Sysworld Limited | Information & communication | 2023 |
| Sysygy-Eo Ltd | Construction | 2024 |
| Syva Health Ltd | Information & communication | 2026 |
| SZD Limited | Real estate | 2021 |
| Szjp Limited | Real estate | 2024 |
| Sztross Limited | Health & social care | 2013 |
| SZY Interiors Limited | Other services | 2016 |
| S’N’D Global Traders Ltd | Wholesale & retail | 2022 |
| T & a Essex Limited | Wholesale & retail | 2015 |
| T & a Essex Properties Ltd | Real estate | 2020 |
| T & M Drives & Patio Ltd | Administrative & support | 2011 |
| T & T Projects London Ltd | Construction | 2022 |
| T Driving School Ltd | Real estate | 2025 |
| T Emetu Associates Limited | Professional & scientific | 2009 |
| T G Building Solutions Limited | Construction | 2018 |
| T H a Developments Ltd | Real estate | 2022 |
| T H Assets Ltd | Financial services | 2019 |
| T Harris Scaffolding Limited | Construction | 2025 |
| T M R Builders Ltd | Construction | 2025 |
| T Power Haulage Limited | Transport & logistics | 2025 |
| T Prazer Limited | Construction | 2008 |
| T S B Civil Engineering Limited | Administrative & support | 2012 |
| T S Sehmbi Consulting Limited | Administrative & support | 2023 |
| T Square Limited | Wholesale & retail | 2021 |
| T U Estates Limited | Real estate | 2020 |
| T&A Rentals Ltd | Real estate | 2025 |
| T&B Concept Ltd | Transport & logistics | 2016 |
| T&C Building Lofts Ltd | Construction | 2023 |
| T&C Ciurciumel Ltd | Construction | 2013 |
| T&D Plumbing & Heating Services Ltd | Construction | 2025 |
| T&D Property Solutions Ltd | Real estate | 2019 |
| T&G Properties Limited | Real estate | 2012 |
| T&G Millennium Services Ltd | Construction | 2018 |
| T&Rc Ltd | Extraterritorial | 1998 |
| T&S Gifts Ltd | Wholesale & retail | 2025 |
| T&S Legal Services Ltd | Professional & scientific | 2026 |
| T&T Technologies Limited | Information & communication | 2021 |
| T-Stones Ltd | Construction | 2007 |
| T. K. Creamer Roofing Limited | Wholesale & retail | 2002 |
| T.L. Projects Limited | Administrative & support | 2021 |
| T.S. Telecom Limited | Wholesale & retail | 2004 |
| T.Tyler Lighting Ltd | Professional & scientific | 2011 |
| T.V. Antoni Properties & Investments Limited | Construction | 1962 |
| T.Y. Installation Ltd | Construction | 2017 |
| T2R Design and Build Ltd | Construction | 2018 |
| T3 Financial Ltd | Financial services | 2019 |
| TA Magic Investments Limited | Real estate | 2024 |
| TA Style Ltd | Other services | 2013 |
| Taano Ltd | Construction | 2015 |
| Tabb Creative Limited | Arts & recreation | 2022 |
| Table & Trolley Ltd | Information & communication | 2026 |
| Tabur Limited | Health & social care | 2023 |