| Smart Transitions Ltd | Other services | 2020 |
| Snowy Beach Productions Limited | Information & communication | 2007 |
| SNS Commerce Ltd | Wholesale & retail | 2021 |
| Snug Apartment Limited | Construction | 2022 |
| Soaring Properties Ltd | Real estate | 2017 |
| SOH Beyond Properties Ltd | Real estate | 2018 |
| SOL Housing Ltd | Real estate | 2018 |
| Sol&Dum Legal Ltd | Professional & scientific | 2020 |
| Solid Gain Investments Limited | Real estate | 2018 |
| Solid State Productions Limited | Information & communication | 2011 |
| Solomon & Thaddeus Ltd | Real estate | 2017 |
| Solution Investment Ltd | Real estate | 2017 |
| Soma Centres Limited | Extraterritorial | 2002 |
| Soma London Ltd | Wholesale & retail | 2019 |
| SON River LLP | | 2021 |
| Sonnet Capital Limited | Real estate | 2018 |
| Sonnet Holdings Limited | Real estate | 2021 |
| Sophie and Luna Limited | Manufacturing | 2014 |
| Soul Safari Leadership Ltd | Other services | 2025 |
| Soulbei UK Ltd | Wholesale & retail | 2021 |
| Sound Accounting Limited | Professional & scientific | 2025 |
| Sound Accounting Services Ltd | Professional & scientific | 2008 |
| Sound Property Solutions Ltd | Real estate | 2018 |
| Southern Industrial Supplies Limited | Manufacturing | 2013 |
| Southpool Limited | Real estate | 1980 |
| Soyoo Ltd | Wholesale & retail | 2019 |
| Space by Proj Ltd | Information & communication | 2025 |
| Space Guru Ltd | Extraterritorial | 2019 |
| Spacepatrol Limited | Information & communication | 2013 |
| Sparcstudio Ltd. | Professional & scientific | 2009 |
| Sparkle Laundrette Limited | Other services | 2011 |
| Spirit Level Design Ltd | Information & communication | 2015 |
| SPM Construction Services Limited | Construction | 2024 |
| Sportsdevhub Ltd | Information & communication | 2024 |
| Sportsmode Ltd | Construction | 2011 |
| Spring 80: 20 Limited | Professional & scientific | 2002 |
| Spring Grove (Hampton) Management Co. Limited | Households | 1981 |
| Sprint Pharma Limited | Wholesale & retail | 2015 |
| Spsid Ltd | Information & communication | 2008 |
| Squaringcircles Design & Photography Ltd | Arts & recreation | 2011 |
| Sr-Star Business Services Ltd | Information & communication | 2011 |
| SRI Development Ltd | Real estate | 2021 |
| Sribo Ltd | Hospitality | 2024 |
| SRL Investment Group Ltd | Financial services | 2024 |
| SRR Foods Ltd | Hospitality | 2024 |
| ST Albans Lodge Residents Association Limited | Households | 1997 |
| ST John-Smith Associates Limited | Professional & scientific | 2012 |
| ST. Marks Hill Management Company Limited | Households | 1969 |
| Stackd Supplements Ltd | Wholesale & retail | 2025 |
| Stagg Auto Ltd | Wholesale & retail | 2026 |
| Staines Road Limited | Real estate | 2011 |
| Stapledon Estate Management Limited | Real estate | 2014 |
| Star Barber Hampton Limited | Other services | 2022 |
| Star PR Limited | Professional & scientific | 2004 |
| Starless Consulting Ltd | Information & communication | 2025 |
| Starling Productions Limited | Information & communication | 2016 |
| State of the Future Ltd | Information & communication | 2025 |
| Statement 7 Ltd | Wholesale & retail | 2012 |
| Station Road Teddington Limited | Real estate | 2021 |
| Stayoung Ltd | Wholesale & retail | 2021 |
| Stefsky Estate Ltd | Real estate | 2022 |
| Stepping Stone Tuition Ltd | Education | 2014 |
| Stepup Tots Limited | Manufacturing | 2025 |
| Steve Macdonald Ltd | Professional & scientific | 2022 |
| Stewardship Estates Ltd | Extraterritorial | 2019 |
| Still Sanguine Limited | Professional & scientific | 2021 |
| Stirling Court (Surbiton) Residents Company Limited | Households | 1991 |
| Stonehaven Translation Solutions Ltd. | Professional & scientific | 2015 |
| Stones Legal Services Limited | Professional & scientific | 2014 |
| Stoney Deep (Teddington) Residents Association Limited | Households | 1976 |
| Stories for OUR Hearts Ltd | Information & communication | 2022 |
| Storplan Racking Limited | Manufacturing | 2000 |
| STP Holding Ltd | Financial services | 2024 |
| Strategy Events Ltd | Administrative & support | 2016 |
| Street Life Limited | Professional & scientific | 2011 |
| Stridingedge Consulting Ltd | Professional & scientific | 2022 |
| Structive Ltd | Professional & scientific | 2021 |
| STS Build Group Ltd | Construction | 2025 |
| Stuart Colman Financial Services Limited | Financial services | 2023 |
| Studio 22 London Limited | Professional & scientific | 2008 |
| Studio Ronde Ltd | Wholesale & retail | 2015 |
| Studio Three Sixty Limited | Manufacturing | 2015 |
| Su-Brit Trading Company Limited | Wholesale & retail | 2025 |
| Substance London Limited | Information & communication | 2018 |
| Sudrey Ltd | Real estate | 2019 |
| SUE Casey Gunn Ltd | Other services | 2012 |
| Suki Consulting Limited | Information & communication | 2012 |
| Sumathi Limited | Information & communication | 2010 |
| Sun & Moon Advisory Ltd | Professional & scientific | 2025 |
| Sun Prime Property Ltd | Real estate | 2017 |
| Sunroh Ltd | Real estate | 2018 |
| Sunshine Accounting Services Ltd | Professional & scientific | 2017 |
| Super Animate Media Ltd | Information & communication | 2010 |
| Supply Webb UK Limited | Wholesale & retail | 2026 |
| Surrey Cafe Limited | Hospitality | 2025 |
| Sussex Research Limited | Financial services | 2001 |
| Sussex Trading Company Limited | Financial services | 2000 |
| SVR Cyber Ltd | Information & communication | 2024 |
| SW Location Ltd | Real estate | 2025 |
| Swan Asset Management Limited | Real estate | 2025 |