| Select Motor Parts Ltd | Wholesale & retail | 2023 |
| Sellify Limited | Wholesale & retail | 2024 |
| Selvam Convenience Store Ltd | Wholesale & retail | 2020 |
| Selworth Developments Ltd | Real estate | 2003 |
| Semicorp Limited | Construction | 2023 |
| Senhury Limited | Administrative & support | 2018 |
| SEO Mummy Ltd | Wholesale & retail | 2023 |
| Seoul Magic Ltd | Wholesale & retail | 2024 |
| Serene Love Limited | Health & social care | 2023 |
| Serene Urban Developments Ltd | Real estate | 2021 |
| Service by Emergency Response Volunteers Serv (Kent) | Transport & logistics | 2021 |
| Servicessmart Ltd | Administrative & support | 2017 |
| Sethi and Satpal Co Ltd | Real estate | 2024 |
| Seven Acre Farm Limited | Agriculture & fishing | 2017 |
| Seven Drops Trading Co Ltd | Wholesale & retail | 2020 |
| Sexy Tropics Ltd | Hospitality | 2025 |
| Sezara Global Limited | Wholesale & retail | 2026 |
| SG Group Holdco Ltd | Financial services | 2025 |
| SG Group London Ltd | Construction | 2019 |
| SG Technologies Group Limited | Manufacturing | 2011 |
| SG Technologies Limited | Manufacturing | 1987 |
| SGA HR Consultancy Ltd | Administrative & support | 2021 |
| SGE Care and Recruitment Limited | Administrative & support | 2019 |
| SH Goods Ltd | Wholesale & retail | 2022 |
| Shae’S Hair and Beauty Ltd | Other services | 2023 |
| Shafs Kitchen Ltd | Hospitality | 2022 |
| Shahid Investments Limited | Real estate | 2024 |
| Shahmeer Shah Groups Limited | Wholesale & retail | 2025 |
| Shakarah Catering Ltd | Hospitality | 2017 |
| Shalom Community Support Services Limited | Health & social care | 2012 |
| Shalom Wealth Limited | Wholesale & retail | 2022 |
| Shapeshifter Records Ltd | Information & communication | 2025 |
| Sharp Aggregates Ltd | Administrative & support | 2023 |
| Sharp Brothers (Skips) Limited | Administrative & support | 2000 |
| Sharp Environmental Limited | Professional & scientific | 2019 |
| Sharp Reclamation Limited | Transport & logistics | 2016 |
| Sharp Skips Limited | Transport & logistics | 1987 |
| Sharp Transport Limited | Transport & logistics | 1997 |
| Sharpatoms Global Limited | Information & communication | 2025 |
| Sharyn Designs Ltd | Professional & scientific | 2016 |
| Shasha Healthcare Limited | Health & social care | 2022 |
| Shaun TM Ltd | Construction | 2025 |
| Shay Financial Services Ltd | Financial services | 2024 |
| Sheikh&Co Limited | Real estate | 2024 |
| Shelter Security Ltd | Administrative & support | 2019 |
| Sherifs Fish Bar Limited | Hospitality | 2018 |
| Shield & Spark Trading Ltd | Wholesale & retail | 2025 |
| Shieldpro Windows Ltd | Construction | 2024 |
| Shindore Limited | Health & social care | 2019 |
| Shireen-E-Hazara Limited | Real estate | 2021 |
| Shiren Boutique Ltd | Wholesale & retail | 2025 |
| SHO Sports Limited | Professional & scientific | 2024 |
| Shosmart Security Ltd | Administrative & support | 2019 |
| Shree Info Limited | Information & communication | 2016 |
| Shreeji Dwelling Ltd | Real estate | 2024 |
| Shreeji Inc Ltd | Health & social care | 2014 |
| Shreeji Training Ltd | Education | 2011 |
| Shreetech Trading Limited | Wholesale & retail | 2024 |
| Shrinathji Supermarket Limited | Wholesale & retail | 2024 |
| SI Civils Ltd | Construction | 2023 |
| Si-Am Ltd | Wholesale & retail | 2022 |
| SIA Trade Ltd | Financial services | 2023 |
| Siahma Ltd | Administrative & support | 2023 |
| Siba Healthcare Ltd | Administrative & support | 2014 |
| Sidney Spencer Horizon Ltd | Real estate | 2025 |
| Sidorova Design Ltd | Professional & scientific | 2020 |
| Siera Ltd | Construction | 2018 |
| Signal N Smoke Ltd | Wholesale & retail | 2025 |
| Signature LUX Ltd | Health & social care | 2024 |
| SIGNEON360 Ltd | Wholesale & retail | 2024 |
| Significant Corporate Services Ltd | Administrative & support | 2018 |
| Sikelela Owen Limited | Arts & recreation | 2023 |
| Silver Crew Ltd | Hospitality | 2021 |
| Silver Inn Ltd | Hospitality | 2019 |
| Silver Kidz Camps UK Limited | Arts & recreation | 2018 |
| Silver Sensitive Goods Ltd | Manufacturing | 2025 |
| Silver Shark Capital Ltd | Professional & scientific | 2021 |
| Silver Shark Homes Ltd | Real estate | 2022 |
| Silver Spring Bureau Ltd | Administrative & support | 2008 |
| Silvertob Property Consult Ltd | Construction | 2025 |
| Simarx Limited | Professional & scientific | 2017 |
| Simi Sadé London Limited | Professional & scientific | 2016 |
| Simple Supplies UK Ltd | Wholesale & retail | 2025 |
| Simply Cleaning Specialists Ltd | Administrative & support | 2012 |
| Simply DIY Limited | Wholesale & retail | 2004 |
| Simply Quality Home Improvements Ltd | Construction | 2019 |
| Simply Tuition Ltd | Information & communication | 2024 |
| Simpson Care Services Ltd | Administrative & support | 2022 |
| Sims Dental Academy Ltd | Education | 2024 |
| Sinclar Limited | Wholesale & retail | 2022 |
| Singh Housing Ltd | Construction | 2024 |
| Singhar Ltd | Wholesale & retail | 2025 |
| Sinners Barbers Ltd | Other services | 2020 |
| SJ Granite Ltd | Manufacturing | 2024 |
| SJ Solution Ltd | Information & communication | 2022 |
| Sjewellery Limited | Wholesale & retail | 2025 |
| SJM Executive Travel Ltd | Transport & logistics | 2026 |
| SKC Properties Limited | Real estate | 2013 |
| Skillsetpro Ltd | Professional & scientific | 2023 |
| Skip Fabrications Limited | Extraterritorial | 2020 |