| SKC Psychology Limited | Health & social care | 2015 |
| Skdr Daily Reset Ltd | Administrative & support | 2026 |
| SKI Bound Limited | Other services | 1984 |
| Skin Maison Limited | Other services | 2025 |
| Skinners Consulting Ltd | Information & communication | 2024 |
| Skins the Skin Experts Ltd | Health & social care | 2023 |
| Skipintro Limited | Professional & scientific | 2004 |
| SKS Productions Ltd | Arts & recreation | 2013 |
| Sky Border UK Import&Export Ltd | Wholesale & retail | 2020 |
| Sky JET Limited | Administrative & support | 1996 |
| Skyy Properties Ltd | Real estate | 2020 |
| Slam JAM Productions Limited | Information & communication | 1988 |
| Sleipnir Capital Ltd | Professional & scientific | 2015 |
| Sloane Consultants Limited | Extraterritorial | 1995 |
| Sloane Demolition and Dismantling Limited | Construction | 2013 |
| Sloop Tech Ltd | Information & communication | 2020 |
| Sloop Tech Services Ltd | Information & communication | 2026 |
| SLS Analytics Ltd | Information & communication | 2021 |
| SM Bags & Luggage Ltd | Wholesale & retail | 2018 |
| SM Power Bags Limited | Wholesale & retail | 2023 |
| Small Mammal Technology Limited | Information & communication | 2013 |
| Smart Indian 2030 Limited | Hospitality | 2025 |
| Smart Media Publishing Limited | Information & communication | 2017 |
| Smart Prolet Ltd | Real estate | 2022 |
| Smart Transactions Group Limited | Information & communication | 2000 |
| Smart Waze Ltd | Wholesale & retail | 2018 |
| Smartbuilt Limited | Real estate | 2018 |
| Smartdontics Limited | Health & social care | 2017 |
| Smartech-Products Ltd | Manufacturing | 2026 |
| Smashedbashed Burgers Kingston Limited | Hospitality | 2024 |
| SMK Consulting Ltd | Professional & scientific | 2010 |
| Smmmh Limited | Real estate | 2021 |
| Smok Properties Limited | Financial services | 2025 |
| Smoke and Watches Limited | Wholesale & retail | 2023 |
| Smooth Skin Clinic Ltd | Wholesale & retail | 2016 |
| Snikpoh Limited | Construction | 2014 |
| Snorkel Limited | Administrative & support | 2018 |
| Snow White Professionals Limited | Water & waste | 2017 |
| Snow White Property Management Ltd | Construction | 2018 |
| Snowgum Property Ltd | Real estate | 2010 |
| SNP Interlink Limited | Wholesale & retail | 2013 |
| SO Delight Limited | Hospitality | 2024 |
| Soarbuck Ltd | Wholesale & retail | 2023 |
| Soffy Ltd | Wholesale & retail | 2018 |
| Softbridge Consultancy Limited | Information & communication | 2004 |
| Sohail Halal Meat Ltd | Wholesale & retail | 2019 |
| Sokio Limited | Real estate | 2020 |
| SOL Holdings LLP | | 2019 |
| SOL Sports Invest Limited | Professional & scientific | 2025 |
| Solaris Innovations Ltd | Wholesale & retail | 2025 |
| Solberry Advisory Limited | Professional & scientific | 2026 |
| Solidsoft Ltd | Information & communication | 2014 |
| Solomon Natural Resources Ltd | Professional & scientific | 2016 |
| Solstice Technology Consulting Ltd | Information & communication | 2021 |
| Some Food Limited | Wholesale & retail | 2025 |
| Somerset Place Management Company Limited | Households | 2000 |
| Somerville Court Management Limited | Real estate | 2004 |
| Sommetix Limited | Households | 1979 |
| Sonfield Limited | Financial services | 2025 |
| Sonnleitner Financial Services Limited | Professional & scientific | 2016 |
| Sophie LH Baker Limited | Real estate | 2023 |
| Sorano Investments Limited | Financial services | 2019 |
| Sorento Solutions Ltd | Other services | 2018 |
| Soulenti Property Ltd | Real estate | 2022 |
| South West Aesthetics Ltd | Manufacturing | 2017 |
| Southborough High School | Education | 2011 |
| Southborough House Residents Association Limited | Extraterritorial | 1998 |
| Southbridge Limited | Hospitality | 2007 |
| Southern Cloud Ltd | Information & communication | 2011 |
| Southernmost Systems Training Ltd | Information & communication | 2022 |
| Southwood Residents Company Limited | Households | 1971 |
| Spacerace Limited | Financial services | 2015 |
| Spargo House Management Company Limited | Households | 2014 |
| Spark Joy London Ltd | Education | 2018 |
| Sparkle Private Limited | Health & social care | 2022 |
| Sparrow Post Limited | Information & communication | 2015 |
| Speakup Theatre Ltd | Arts & recreation | 2022 |
| Speed Motors Limited | Wholesale & retail | 2014 |
| Speedy Innovations Ltd | Wholesale & retail | 2017 |
| Spegan Properties Ltd | Real estate | 2021 |
| Spiralize Studio Ltd | Information & communication | 2026 |
| Spire Court Residents Association Limited | Households | 1964 |
| Spirry Ltd | Wholesale & retail | 2026 |
| Spitting Flames Limited | Wholesale & retail | 2023 |
| Sports Impact Limited | Administrative & support | 2001 |
| Spot Blue International Property Limited | Real estate | 2003 |
| Spot Blue Limited | Information & communication | 2006 |
| Spotlight Consulting PVT Ltd | Information & communication | 2023 |
| SPR Property Management Limited | Households | 2007 |
| Spring Earth London Ltd | Manufacturing | 2022 |
| Sproutwealth Ltd | Real estate | 2021 |
| Sqppc Ltd | Construction | 2020 |
| Squidcard Ltd | Financial services | 2000 |
| Squiggle Therapy Ltd | Arts & recreation | 2025 |
| Squint Music Ltd | Information & communication | 2014 |
| SRI Car Repair Ltd | Wholesale & retail | 2023 |
| SRI Sundara Krishna SAI Consulting Limited | Professional & scientific | 2025 |
| SRS Consultants Ltd | Professional & scientific | 2025 |
| SRS Holdco Ltd | Financial services | 2026 |
| SRS Properties Surrey Ltd | Real estate | 2019 |