| Sofia Bakers Group Limited | Hospitality | 2024 |
| Sofia Bakers Limited | Hospitality | 2024 |
| Sofia MAR Ltd | Construction | 2020 |
| Soft Planner Ltd | Wholesale & retail | 2026 |
| Softglow Aesthetics Ltd | Health & social care | 2025 |
| Softlogik Ltd | Wholesale & retail | 2021 |
| Softtech Business Solutions Limited | Information & communication | 2007 |
| Software Dojo Ltd | Information & communication | 2021 |
| Sohum Orisun Ltd | Arts & recreation | 2022 |
| Sohzain Ltd | Wholesale & retail | 2025 |
| Soinec Global Limited | Construction | 2019 |
| Solacube Limited | Health & social care | 2016 |
| Solami Snipes Ltd | Financial services | 2025 |
| Solarize Visuals Ltd | Professional & scientific | 2026 |
| Solid Choice Limited | Wholesale & retail | 2025 |
| Solid Way Ltd | Manufacturing | 2023 |
| Solidbybunmi Limited | Wholesale & retail | 2018 |
| Solidedge Contractors Limited | Construction | 2026 |
| Solidia Ltd | Construction | 2024 |
| Solidr Ltd | Construction | 2024 |
| Solpath Solutions Limited | Health & social care | 2025 |
| Soluna. Limited | Wholesale & retail | 2022 |
| Solvera Services Ltd | Information & communication | 2026 |
| SOMA-76 Ltd | Administrative & support | 2017 |
| Sonehri Services Ltd | Information & communication | 2022 |
| Sono Accountancy Limited | Professional & scientific | 2017 |
| Sonodirect Ltd | Health & social care | 2015 |
| Sons of Bethlehem Limited | Other services | 2024 |
| Sons of Bethlehem Sporting Club Ltd | Arts & recreation | 2025 |
| Sooxos Group Ltd | Wholesale & retail | 2021 |
| Sophie & Jasmine London Ltd | Wholesale & retail | 2021 |
| Sorelia Limited | Manufacturing | 2025 |
| Sorted Solutions Limited | Wholesale & retail | 2024 |
| SOS Skips Ltd | Manufacturing | 2025 |
| Sotra Management Ltd | Information & communication | 2021 |
| Soul and Sound C.I.C. | Health & social care | 2010 |
| Soulrise Community Support CIC | Health & social care | 2025 |
| Soulrise International Academy Ltd | Education | 2026 |
| Soulworker Ltd | Construction | 2016 |
| Sounds & Spirits Ltd | Hospitality | 2024 |
| Souq Hayaa Limited | Wholesale & retail | 2025 |
| South & East Fashion Ltd | Wholesale & retail | 2024 |
| Southcrown Limited | Real estate | 1985 |
| Southwold Consultants Ltd | Real estate | 2021 |
| Sovereign Lift Trucks Co. Limited | Manufacturing | 1999 |
| Sovereign Liftrucks Sales Ltd | Manufacturing | 2003 |
| Sowee Ltd | Administrative & support | 2016 |
| SP Fast Track PVT Ltd | Administrative & support | 2023 |
| Space Care Properties Ltd | Real estate | 2025 |
| Space Craft Interiors Limited | Wholesale & retail | 2024 |
| Space Make Solutions Ltd | Construction | 2025 |
| Space Marathon Group Ltd | Manufacturing | 2026 |
| Spagha Ltd | Wholesale & retail | 2025 |
| Spainker UK Limited | Wholesale & retail | 2018 |
| Spark Accounts Ltd | Wholesale & retail | 2016 |
| Sparkle Cleaning & Maintenance Ltd | Administrative & support | 2025 |
| Sparkle Waste Ltd | Water & waste | 2011 |
| Sparkling Bay Ltd | Wholesale & retail | 2025 |
| Sparkling Events Ltd | Administrative & support | 2015 |
| Sparkling Stones Limited | Other services | 2014 |
| Sparko Ltd | Transport & logistics | 2017 |
| Sparky Group Ltd | Construction | 2025 |
| SPEAK4ME International Ltd | Transport & logistics | 2025 |
| Speciale Ltd | Administrative & support | 2018 |
| Specstore Opticians Limited | Wholesale & retail | 2007 |
| Spectacular (UK) Ltd | Other services | 2008 |
| Spectacularkidz Day Nursery Ltd | Education | 2010 |
| Spectrum Healthcare Services Ltd | Health & social care | 2023 |
| Speed Cement Ltd | Manufacturing | 2025 |
| Speed Serv HGV Ltd | Transport & logistics | 2015 |
| Speedbitz Ltd | Wholesale & retail | 2017 |
| Spencers Property Development Ltd | Real estate | 2022 |
| Spetsnaz Limited | Administrative & support | 2013 |
| Spice House Barking Ltd | Hospitality | 2022 |
| Spine Technologies (Wholesale) Limited | Wholesale & retail | 2019 |
| Spinel Contractors Limited | Construction | 2011 |
| Spiralu Ltd | Transport & logistics | 2016 |
| Spiritual Warrior Products Ltd | Wholesale & retail | 2020 |
| Splendclean Ltd | Administrative & support | 2013 |
| Spotclean Ltd | Other services | 2014 |
| Spotless Plus Service Ltd | Administrative & support | 2025 |
| Spray and Bake Powder Coaters Ltd | Other services | 2018 |
| Spread by Chesed Ltd | Financial services | 2022 |
| Spring Garden Homes UK Ltd | Real estate | 2025 |
| Spring Solicitors LLP | | 2010 |
| Springcare Recruitment Ltd | Health & social care | 2018 |
| Springfield Solicitors Limited | Professional & scientific | 2010 |
| Spritzen Ltd | Administrative & support | 2019 |
| Spud Stop Limited | Hospitality | 2025 |
| Spur Restaurant Limited | Hospitality | 2025 |
| Spycon Security Ltd | Construction | 2022 |
| SQAN2 Ltd | Professional & scientific | 2026 |
| Square Circle Care Services Limited | Administrative & support | 2025 |
| Square Glazing Ltd | Construction | 2010 |
| SR Car Electrician Ltd | Wholesale & retail | 2025 |
| SR Car Services Ltd | Wholesale & retail | 2018 |
| SR Graphics & Tech Ltd | Information & communication | 2024 |
| Sraeo Ltd | Professional & scientific | 2018 |
| SRE Automotive Limited | Wholesale & retail | 2025 |
| Sree Vaanara Ltd | Hospitality | 2025 |