| Spire Contracts Ltd | Construction | 2009 |
| Spire Investments Limited | Real estate | 2009 |
| Spirit of Afrika Rising Ltd | Construction | 2020 |
| Splendorhousingsupport Limited | Administrative & support | 2024 |
| Spoor-Tech Ltd | Construction | 2002 |
| Sportsjobfinder Limited | Arts & recreation | 2018 |
| Spotlight Alpine CIC | Households | 2021 |
| Sprags Ltd | Construction | 2009 |
| Spread Eagle Sailing Club Limited | Other services | 2000 |
| Spring Fresh Ltd | Real estate | 2020 |
| Springett 5 Limited | Information & communication | 2025 |
| Springfield Residential Care Limited | Health & social care | 2023 |
| Sprs Services Ltd | Construction | 2017 |
| SPS Plumbing Limited | Construction | 2012 |
| SPV Transport Ltd | Transport & logistics | 2020 |
| Spyrex Ltd | Transport & logistics | 2021 |
| Square Space London Ltd | Information & communication | 2024 |
| Squares Accessories Ltd | Other services | 2019 |
| Squares Beauty Hair and Cosmetic Limited | Wholesale & retail | 2023 |
| Sr&C Limited | Construction | 2022 |
| SRB Logistics & Care Services Ltd | Health & social care | 2022 |
| SRB Power Limited | Wholesale & retail | 2003 |
| Sreevi Ltd | Professional & scientific | 2024 |
| SRG Achim Ltd | Wholesale & retail | 2024 |
| SRN Trade Ltd | Wholesale & retail | 2026 |
| Sryy Twins Ltd | Construction | 2016 |
| SS Building Construction Ltd | Construction | 2024 |
| SS Global Transport Services Ltd | Transport & logistics | 2026 |
| SSC 99 UK Limited | Education | 2026 |
| SSC1 Limited | Construction | 2023 |
| SSE Utilities Limited | Construction | 2019 |
| SSG Brickwork Ltd | Construction | 2017 |
| Ssola Limited | Extraterritorial | 2020 |
| Ssom Limited | Information & communication | 2019 |
| Sspb Limited | Real estate | 2022 |
| SSR Property & Management Ltd | Real estate | 2026 |
| SSS88SSS Ltd | Construction | 2025 |
| ST Clements Walk Block J Management Company Limited | Households | 1990 |
| ST Clements Walk Block K Management Company Limited | Households | 1990 |
| ST Clements Walk Block P Management Company Limited | Households | 1990 |
| ST Clements Walk Block S Management Company Limited | Households | 1990 |
| ST Clements Walk Block T Management Company Limited | Households | 1990 |
| ST Johns Carpentry and Construction Ltd | Manufacturing | 2025 |
| ST Stephens Management Company Limited | Real estate | 2015 |
| ST. Cedds (South Ockendon) Management Company Limited | Households | 1996 |
| ST. Ediths Court Management Company Ltd. | Real estate | 1999 |
| ST. Thomas Catholic Club Limited | Other services | 2002 |
| St.Lawrence Caravans Limited | Hospitality | 1965 |
| St.Michaels Close (Mill Road) Management Company Limited | Households | 1989 |
| Stadtsys Ltd | Information & communication | 2021 |
| Stallions Fish Ltd | Hospitality | 2023 |
| Stalog Ltd | Transport & logistics | 2022 |
| Stalwart Holdings UK LP | | 2024 |
| Stambuli Services Ltd | Construction | 2011 |
| Stand Art Caravans Ltd | Wholesale & retail | 2023 |
| Standard Thermal Ltd | Construction | 2020 |
| Standard Thermal Solutions Ltd | Construction | 2020 |
| Stanley Facility Service Limited | Administrative & support | 2025 |
| Star Butcher Grays Ltd | Wholesale & retail | 2024 |
| Star Carz Limited | Transport & logistics | 2019 |
| Star Marketing Ltd | Administrative & support | 2025 |
| Star Windscreens Limited | Wholesale & retail | 2011 |
| Starboy Grill Ltd | Hospitality | 2022 |
| Starfit Installations Ltd | Construction | 2017 |
| Starline Estates Ltd | Real estate | 2023 |
| Starlit Consultancy Ltd | Professional & scientific | 2021 |
| Starting SEO Ltd | Professional & scientific | 2019 |
| Startup IT Solutions Ltd | Information & communication | 2021 |
| Station Hand Car Wash Dagenham Ltd | Administrative & support | 2022 |
| Statom Group Limited | Construction | 2013 |
| Statom Group North Limited | Construction | 2023 |
| Statom Plant Limited | Construction | 2019 |
| Statom Precast Limited | Manufacturing | 2023 |
| Statom Remediation Ltd | Water & waste | 2024 |
| Statom Strategic Projects Ltd | Construction | 2024 |
| Statuscake Limited | Information & communication | 2022 |
| Stavady Logistics Ltd | Transport & logistics | 2021 |
| STD Rail Services Ltd | Professional & scientific | 2011 |
| Steel Capital Partners Ltd | Professional & scientific | 2014 |
| Steelform Construction Ltd | Construction | 2025 |
| Steepleview RTM Company Limited | Households | 2015 |
| Stef Solution Limited | Transport & logistics | 2013 |
| Stefan Coman Ltd | Construction | 2014 |
| Stel&Stars Transport Ltd | Transport & logistics | 2024 |
| Stella Bargain Store Ltd | Wholesale & retail | 2017 |
| Stellar Data Networks Ltd | Other services | 2026 |
| Stemich Consultancy Limited | Information & communication | 2015 |
| Stemich Property Ltd | Real estate | 2024 |
| STEP-2-DEGREE Ltd | Education | 2025 |
| Stephenblue Limited | Wholesale & retail | 2020 |
| STG Haulage Limited | Transport & logistics | 2025 |
| Stifford Clays Hotel Limited | Hospitality | 2015 |
| Stifford Tyres & Services Ltd | Wholesale & retail | 2020 |
| Stirling Apparel Ltd | Wholesale & retail | 2019 |
| Stitch & Prints Limited | Manufacturing | 2017 |
| Stix and Stones Construction Ltd | Construction | 2023 |
| Stix and Stones Homes Limited | Construction | 2023 |
| STM Logistics Limited | Wholesale & retail | 2017 |
| STN Property Management Ltd | Real estate | 2020 |
| Stock United Limited | Construction | 2020 |