| Streamline Tech Ltd | Information & communication | 2022 |
| Streatleigh Court Management Limited | Real estate | 1984 |
| Street 2 Elite Ltd | Arts & recreation | 2025 |
| Street Science Ltd | Wholesale & retail | 2026 |
| Streets Property (Southern) Ltd | Real estate | 2025 |
| Strength Health Performance Fitness Ltd | Other services | 2016 |
| Stretford Road Limited | Other services | 2021 |
| Strike 366 Limited | Information & communication | 2024 |
| Striking FUN Limited | Information & communication | 2024 |
| Strip Bars (Gloucester) Ltd | Hospitality | 2022 |
| Strive Contracts Limited | Manufacturing | 2014 |
| Stroe Viorel Ltd | Transport & logistics | 2019 |
| Stroika International Investments Limited | Professional & scientific | 2024 |
| Stroika International Ltd | Professional & scientific | 2022 |
| Strollmoor Limited | Real estate | 1972 |
| Strong Current Group Limited | Construction | 2023 |
| Stronger YOU C.I.C. | Health & social care | 2022 |
| Strongroom Group Limited | Financial services | 2026 |
| Strongroom Holdings Limited | Financial services | 2019 |
| Strongroom Self Storage (Salisbury) Limited | Real estate | 2019 |
| Strongroom Self Storage Limited | Real estate | 2007 |
| Stroud Heights Caravan Park Ltd | Construction | 2011 |
| Stroud Property Management Ltd | Real estate | 2012 |
| Structural Group Limited | Construction | 2015 |
| Structural Repairs Ltd | Construction | 2006 |
| Sts-Vlad Ltd | Transport & logistics | 2020 |
| STU Vincent Education Limited | Education | 2025 |
| Stuart Barfoot Garden and Landscape Design Ltd | Administrative & support | 2014 |
| Stuart Biggs Carpentry Limited | Construction | 2016 |
| Stuart Flitton Media Limited | Information & communication | 2016 |
| Stuart Howitt's Initial Tenancy Limited | Households | 2024 |
| Stuart Turner Estates Limited | Construction | 2018 |
| Stuarts House Care Limited | Health & social care | 2013 |
| Stub Media Limited | Professional & scientific | 2025 |
| Stubbs Builders Limited | Construction | 2015 |
| Stucchi & Co. Limited | Hospitality | 2019 |
| Student Property Developments Limited | Construction | 2017 |
| Studio 12 Property Acquisitions Ltd | Administrative & support | 2026 |
| Studio 23 Prints Limited | Manufacturing | 2026 |
| Studio 33 Design UK Limited | Wholesale & retail | 2016 |
| Studio 44 Media Limited | Manufacturing | 2019 |
| Studio Adam Morten Ltd | Arts & recreation | 2018 |
| Studio BAD Ltd | Professional & scientific | 2017 |
| Studio Cadogan Ltd | Professional & scientific | 2022 |
| Studio Legale Italiano Ltd. | Administrative & support | 2005 |
| Studio Legale Ltd | Administrative & support | 2005 |
| Studio Legale Nigro Ltd | Administrative & support | 2005 |
| Studio Mahala Limited | Professional & scientific | 2020 |
| Studio Mode Ltd | Professional & scientific | 2006 |
| Studio Ninety Two Limited | Other services | 2020 |
| Studio Seven Design Services Ltd | Professional & scientific | 2026 |
| Studio Twentynine Limited | Other services | 2019 |
| Studio Wilde Ltd. | Information & communication | 2019 |
| Stuffed Gourmet Trailers Ltd | Hospitality | 2026 |
| Stuffed GT Neet Ltd | Hospitality | 2026 |
| Stupid Tourist Clothing Limited | Wholesale & retail | 2025 |
| Sturt & Company Limited | Real estate | 2012 |
| Stu’S Shepherds Pies Ltd | Extraterritorial | 2023 |
| Style Hair & Beauty Salon Ltd | Other services | 2015 |
| Style Interiors (Hampshire) Limited | Professional & scientific | 2013 |
| Style My Curls Ltd | Wholesale & retail | 2016 |
| Styled by MAH Ltd | Information & communication | 2025 |
| Stylefront Holdings Limited | Real estate | 2015 |
| Stylefront London Limited | Construction | 2013 |
| Stylemerge Limited | Wholesale & retail | 2026 |
| Stylzenharmony Hair Ltd | Other services | 2023 |
| SU Consultants Limited | Administrative & support | 2026 |
| Suavettes Cleaning Limited | Households | 2017 |
| Suay Locum Ltd | Wholesale & retail | 2023 |
| SUB Stop Ltd | Hospitality | 2015 |
| SUB40TECH Ltd | Information & communication | 2019 |
| Suba Homes Limited | Real estate | 2025 |
| Subsea Xplorer Limited | Information & communication | 2024 |
| Subtom Ltd | Manufacturing | 2025 |
| Succeed Home Tutoring Ltd | Education | 2024 |
| Succes Retail Limited | Wholesale & retail | 2024 |
| Success Sublime Property Ltd | Real estate | 2024 |
| Succi & Nash Heavy Lifting Ltd | Manufacturing | 2025 |
| Succinct Solutions Limited | Professional & scientific | 2007 |
| Suchodolski Transport Ltd | Transport & logistics | 2016 |
| SUE Stebbing Consultancy Ltd | Professional & scientific | 2026 |
| Sueno Building and Development Ltd | Construction | 2024 |
| Sugiura Rensei Juku UK Branch Ltd | Education | 2025 |
| SUI Generis Lignarius Ltd | Manufacturing | 2023 |
| Suitable Heating Solutions Limited | Construction | 2010 |
| Suiteforge Limited | Information & communication | 2026 |
| Sujanara Ltd. | Professional & scientific | 1989 |
| Sukatt Ltd | Information & communication | 2015 |
| Sukhbir Singh Gill Ltd | Professional & scientific | 2019 |
| Sukhdev Properties Limited | Real estate | 2023 |
| Sukhmani Capital Limited | Real estate | 2026 |
| Sullivan Consulting Solutions Ltd | Professional & scientific | 2025 |
| Sullivan-Rose Rentals Ltd | Real estate | 2020 |
| Summer PUB Co Ltd | Hospitality | 2017 |
| Summerbridge Group Ltd | Wholesale & retail | 2018 |
| Summit Air Park Ltd | Arts & recreation | 2026 |
| Summit Carpentry South Ltd | Wholesale & retail | 2026 |
| Summit Films Ltd | Information & communication | 2007 |
| Summit Golf Academy Ltd | Arts & recreation | 2026 |
| Summit London Recruitment Ltd | Administrative & support | 2025 |