| Seres Automotive UK Limited | Other services | 2013 |
| Serio Consultants Ltd | Professional & scientific | 2020 |
| Serviced Apartment Real Estate (New Malden) Limited | Real estate | 2022 |
| Settletrack Ltd | Professional & scientific | 2026 |
| Sevan Caterers (CP) Limited | Hospitality | 1992 |
| Sevan Caterers (Vauxhall) Limited | Hospitality | 1975 |
| Sevan Leisure Holdings Limited | Hospitality | 1997 |
| Sevan Properties (2025) Limited | Real estate | 1999 |
| Seven Billions Construction Ltd | Construction | 2025 |
| Seven Billions Ltd | Construction | 2026 |
| Seven Crowns Landscaping and Gardening Ltd | Administrative & support | 2020 |
| SF Portfolio Ltd | Real estate | 2024 |
| SGP Precision UK Ltd. | Health & social care | 2017 |
| SH Collective Consultancy Limited | Professional & scientific | 2022 |
| Shaamili Limited | Wholesale & retail | 2024 |
| Shani Imaging Limited | Wholesale & retail | 2012 |
| Shanmalini Limited | Wholesale & retail | 2017 |
| Shannon Corner Service Centre Limited | Wholesale & retail | 2011 |
| Shazley Ltd | Hospitality | 2025 |
| SHE Beauty Ltd | Other services | 2011 |
| Shelfline Promotional Consultancy Limited | Professional & scientific | 1982 |
| Shell & Construction Ltd | Construction | 2021 |
| Shell Construction Limited | Construction | 2016 |
| Shelley Estate Holdings Ltd | Households | 2025 |
| Shenzhen Jichuang Co Ltd | Wholesale & retail | 2025 |
| Shezan Limited | Real estate | 1990 |
| SHFF1 Limited | Administrative & support | 2019 |
| SHFF2 Limited | Administrative & support | 2019 |
| Shield Security & FM Ltd | Administrative & support | 2025 |
| Shinetutors Ltd | Education | 2024 |
| Shiraz Mirza Community Hall Trust | Administrative & support | 2003 |
| Shirbiny Medical Limited | Health & social care | 2014 |
| Shisha Coffee Bar Ltd | Wholesale & retail | 2020 |
| Shiva Estates Limited | Real estate | 2023 |
| Shivish Limited | Real estate | 2026 |
| Shivlsh Solutions Limited | Real estate | 2026 |
| Shivshakti Nivas Ltd. | Health & social care | 2014 |
| Short Sales Ltd | Professional & scientific | 2026 |
| Shot.By.Eli Limited | Information & communication | 2024 |
| Shree Hari Estate Limited | Real estate | 2021 |
| Shreena Property Limited | Real estate | 2022 |
| Shri Minakshi Investments Ltd | Real estate | 2022 |
| SHY City Fashion Limited | Manufacturing | 2025 |
| Sicurezza Ltd | Administrative & support | 2019 |
| Siddh & Siyaa Ltd | Real estate | 2024 |
| SIG Cleaning Services Ltd | Administrative & support | 2019 |
| Sigma Management Consultancy Limited | Professional & scientific | 2011 |
| Signal Connections Limited | Education | 2007 |
| Signal Risk UK Ltd | Professional & scientific | 2022 |
| Signature Paintworks Ltd | Construction | 2025 |
| Signify Properties 2008 LLP | | 2008 |
| Sikdorak Limited | Extraterritorial | 2024 |
| Siliconnsavvy Ltd | Information & communication | 2023 |
| Silph Co. Limited | Wholesale & retail | 2024 |
| Silvan's Barbers Ltd | Other services | 2018 |
| Silverbelle Ltd | Real estate | 2024 |
| Sima Brothers Limited | Wholesale & retail | 2010 |
| Simon Gardening Ltd | Administrative & support | 2025 |
| Simple Business Consultancy Ltd | Professional & scientific | 2023 |
| Simply Grill Ltd | Hospitality | 2020 |
| Sinabro Trading Ltd | Hospitality | 2017 |
| SIR Sun Takeway & Restaurant Ltd | Hospitality | 2021 |
| Siri Holdings Limited | Real estate | 2021 |
| Sistra Care Ltd | Health & social care | 2026 |
| Site OPS Crew Ltd | Administrative & support | 2026 |
| SIX ARK Stars Limited | Financial services | 2026 |
| SIX Days Film Limited | Information & communication | 2019 |
| SIX Two Limited | Information & communication | 2004 |
| Sixteenfifteen Ltd | Education | 2023 |
| SJ Hallam Consulting Ltd | Professional & scientific | 2017 |
| SJK Technologies Limited | Administrative & support | 2010 |
| SK Geer Advisory Limited | Professional & scientific | 2026 |
| SK Realty Investments Ltd | Real estate | 2024 |
| Skin New Malden Ltd | Other services | 2024 |
| Skma New Malden Limited | Education | 2023 |
| Skma VIA Fortis Ltd | Education | 2026 |
| Sky Valley Technology Ltd | Real estate | 2023 |
| Skylark Health Ltd | Professional & scientific | 2020 |
| Skyrock Holdings Ltd | Real estate | 2025 |
| Sleekflow Technologies Company Limited | Information & communication | 2022 |
| Sleemco Limited | Professional & scientific | 2020 |
| Slmango Ltd | Health & social care | 2018 |
| Slonie Ltd | Real estate | 2023 |
| Smart Freight Ltd | Information & communication | 2024 |
| Smart Sentech International Ltd | Professional & scientific | 2024 |
| SME Global Consultants Limited | Professional & scientific | 2025 |
| Smileflight Ltd | Financial services | 2016 |
| Smokings Kitchen Ltd | Hospitality | 2019 |
| Smsquare Financial Services Ltd | Financial services | 2024 |
| Smyle Management Limited | Households | 2021 |
| Snap Shot Coffee Ltd | Hospitality | 2020 |
| Snaxx Ltd | Real estate | 2022 |
| Sneaker Safe Ltd | Wholesale & retail | 2021 |
| SNEAKSUPPLY75 Ltd | Wholesale & retail | 2023 |
| Snhfoto Ltd | Professional & scientific | 2020 |
| Snhvideo Limited | Information & communication | 2023 |
| SNJ Global UK Ltd | Wholesale & retail | 2021 |
| SNM Consulting Services Limited | Health & social care | 2014 |
| SNR Design Services Limited | Information & communication | 2013 |
| Snuggles Inc Ltd | Extraterritorial | 2023 |