| Steer Smart Driving School Ltd | Education | 2025 |
| Stellar Finance Limited | Professional & scientific | 2014 |
| Stellar Genesis Ltd | Wholesale & retail | 2024 |
| Stellar Motors Ltd | Wholesale & retail | 2022 |
| Stem Tuition Ltd | Education | 2018 |
| Stephanie Clark Hairdressing Ltd | Other services | 2026 |
| Stephen Bird Electrics Limited | Construction | 2013 |
| Stephen Simeon Ventures Limited | Information & communication | 2023 |
| Stepso Limited | Health & social care | 2022 |
| Sterling Contractors Limited | Professional & scientific | 2015 |
| Steve Prower Temporary Works Limited | Professional & scientific | 2017 |
| Steve's Property Care & Repair Limited | Construction | 2015 |
| Stoa Trades Ltd | Information & communication | 2023 |
| Stockmulti Limited | | 1989 |
| Stoke ROW Steam & Vintage Club Ltd | Extraterritorial | 2015 |
| Stone Cold Marketing Ltd | Professional & scientific | 2025 |
| Stonebridge (Refurbishments) Ltd | Construction | 2020 |
| Stonebridge(Berkshire) Ltd | Construction | 2019 |
| Stonefloats Ltd | Professional & scientific | 2005 |
| Storyworlds Studios Ltd | Information & communication | 2019 |
| Strategy Stories Ltd | Information & communication | 2024 |
| Straterris Ltd | Professional & scientific | 2025 |
| Stratoreflection Limited | Professional & scientific | 2023 |
| Stratoskey Global Ltd | Professional & scientific | 2024 |
| Street Dough Ltd | Hospitality | 2019 |
| Strive Sports Ltd | Education | 2025 |
| Stuart MC Dowall Limited | Administrative & support | 1989 |
| Studio Figura International Limited | Real estate | 2018 |
| Studiocvv London Ltd | Professional & scientific | 2024 |
| Styled 4 Ltd | Wholesale & retail | 2022 |
| Styled 4 Recruitment Limited | Administrative & support | 2022 |
| Styled Sensei Ltd | Wholesale & retail | 2023 |
| Stylist Africa Limited | Wholesale & retail | 2014 |
| Sublishop Ltd | Wholesale & retail | 2022 |
| Sulfers Technology Limited | Information & communication | 2020 |
| Summer Lounge Ltd | Hospitality | 2021 |
| Summit Power Limited | Construction | 2022 |
| Summit Utilities Ltd | Construction | 2015 |
| Sun Enterprises Limited | Wholesale & retail | 2019 |
| Sun Jelly Ltd | Wholesale & retail | 2018 |
| Sundial Accounting Limited | Professional & scientific | 2017 |
| Sunhouse Property Ltd | Real estate | 2022 |
| Sunningdale & Wentworth Roofing Services Ltd | Construction | 2015 |
| Sunraj Investments Ltd | Real estate | 2021 |
| Sunray Investments Limited | Manufacturing | 1994 |
| Sunset Farm Operations Ltd | Real estate | 2026 |
| Sunshine Transport Limited | Transport & logistics | 2014 |
| Sunspeed Solutions Ltd | Transport & logistics | 2024 |
| Sunteck IT Consultancy Limited | Information & communication | 2022 |
| Super LED Lights Ltd | Wholesale & retail | 2025 |
| Super Prim Accessories Ltd | Wholesale & retail | 2023 |
| Super Prim Drycleaners Ltd | Other services | 2019 |
| Super Song Oriental Foods Ltd | Wholesale & retail | 2025 |
| Super Sparky Ltd | Construction | 2025 |
| Superb Care Services Ltd | Administrative & support | 2018 |
| Supercar Solutions Limited | Wholesale & retail | 2016 |
| Superior Interiors Limited | Construction | 2003 |
| Superior Service Highways and Logistics Ltd | Transport & logistics | 2018 |
| Supernova Leads Ltd | Information & communication | 2025 |
| Supply & Demand Vehicles Ltd | Wholesale & retail | 2025 |
| SUPPORT4ALL LKC Community Interest Company | Health & social care | 2024 |
| Surface 360 Ltd | Wholesale & retail | 2014 |
| Surfandsand Ltd | Wholesale & retail | 2022 |
| Surrey Goldcrest Basketball Club Ltd | Arts & recreation | 2025 |
| Surrey Plumbing and Heating Specialists Ltd | Construction | 2013 |
| Sushi Newbury Ltd | Hospitality | 2025 |
| Sussex Meats Limited | Wholesale & retail | 2016 |
| Sutherland Michael Limited | Construction | 2015 |
| SV Homes Limited | Construction | 2018 |
| Svoboda Ltd | Real estate | 2020 |
| SVR Bracknell Limited | Hospitality | 2025 |
| SW Improve House Ltd | Construction | 2026 |
| Swan Recruitment Services Ltd | Administrative & support | 2026 |
| Swapbox Ltd | Wholesale & retail | 2025 |
| SWEETS4HK Ltd | Manufacturing | 2024 |
| Sweettastic Bakes & Gifts Ltd | Manufacturing | 2021 |
| Sweta's Kitchen Ltd | Hospitality | 2022 |
| Swift Birds Ltd | Professional & scientific | 2025 |
| Swift Cable Jointing Services Ltd | Energy | 2024 |
| Swimskool Limited | Education | 2021 |
| Swinley Bike Hub Limited | Administrative & support | 2014 |
| Swissqprint UK Limited | Wholesale & retail | 2019 |
| Symphonic Integration Limited | Information & communication | 2014 |
| Syndicate Sounds Ltd | Arts & recreation | 2026 |
| Syngenta Grimsby Limited | Extraterritorial | 2000 |
| Syngenta Holdings Limited | Professional & scientific | 2000 |
| Syngenta Limited | Agriculture & fishing | 1992 |
| Syngenta Pensions Trustee Limited | Financial services | 2000 |
| Syngenta Seeds Limited | Agriculture & fishing | 1938 |
| Syngenta UK Limited | Manufacturing | 1965 |
| Synistic Limited | Hospitality | 2016 |
| Synxchrom Ltd | Manufacturing | 2021 |
| Syquence Limited | Professional & scientific | 2004 |
| T Burnes Lighting Limited | Construction | 2011 |
| T Kartapanis Limited | Arts & recreation | 2025 |
| T P Talent Ltd | Professional & scientific | 2019 |
| T&C Logistics Ltd | Transport & logistics | 2025 |
| T&H Living Ltd | Households | 2022 |
| T&R Group Services Limited | Transport & logistics | 2020 |
| T2 Logistics Limited | Transport & logistics | 2019 |