| Stone Island (UK) Retail Limited | Wholesale & retail | 2022 |
| Stone Jewellery LAB Limited | Wholesale & retail | 2020 |
| Stone Jewellery Manufacturing Limited | Wholesale & retail | 2020 |
| Stone Soup VFX Ltd | Arts & recreation | 2015 |
| Stonearch Homes Limited | Real estate | 2024 |
| STONEBRIDGE27 Limited | Households | 2017 |
| Stoneman Trading Limited | Real estate | 2002 |
| Stoneshow Limited | Households | 1988 |
| Stop Repossession UK Ltd | Professional & scientific | 2019 |
| Storeton Hall Estate Management Company Limited | Households | 2020 |
| Storeyco Ltd | Professional & scientific | 2024 |
| Stork Brothers Ltd | Real estate | 2015 |
| Strange Lands Limited | Information & communication | 2023 |
| Stranz Ltd | Other services | 2006 |
| Stratefy Ltd | Information & communication | 2024 |
| Strategic Innovative Operations Ltd | Professional & scientific | 2023 |
| Strategic People Insights Limited | Professional & scientific | 2022 |
| Strategic Resources (Holdings) Limited | Professional & scientific | 2015 |
| Strategic Risk & Compliance Consultancy Limited | Professional & scientific | 2022 |
| Strategic Shift Consulting Limited | Professional & scientific | 2024 |
| Strategiq Commissioning Consultancy Limited | Professional & scientific | 2025 |
| Strategis Investments Ltd | Real estate | 1999 |
| Strategy Solutions FZE Ltd | Information & communication | 2024 |
| Strathmore Care Home Limited | Health & social care | 1999 |
| Stratos Technologies Ltd. | Information & communication | 2022 |
| Stratton Creber Limited | Professional & scientific | 2004 |
| Stratum Clinical Limited | Information & communication | 2021 |
| Stratus Acquisition Limited | Financial services | 2024 |
| Streamline Accountancy Limited | Professional & scientific | 2006 |
| Streamline Digital Consulting Limited | Professional & scientific | 2023 |
| Streamline Engineering Ltd | Professional & scientific | 2026 |
| Streampar Limited | Households | 1981 |
| Strecon Ltd | Professional & scientific | 2019 |
| Stree Seva CIC | Public administration | 2025 |
| Street Lane Dental Training Ltd. | Health & social care | 2002 |
| Stresa Transport Ltd | Transport & logistics | 2016 |
| Strider Tech Limited | Professional & scientific | 2026 |
| Strike Chords Limited | Administrative & support | 2022 |
| Strikes HCE Limited | Administrative & support | 2020 |
| Strikes Property Services Limited | Administrative & support | 2012 |
| Strium Limited | Professional & scientific | 2019 |
| Strivacity UK Ltd. | Information & communication | 2025 |
| Strong ARM Finance Ltd | Professional & scientific | 2017 |
| Strong Box Security Systems Limited | Administrative & support | 2014 |
| Strong Fitness Project Ltd | Arts & recreation | 2016 |
| Strong Marketing and Communications Limited | Professional & scientific | 2019 |
| Stronglink Computing Ltd | Professional & scientific | 1998 |
| Struan Court Management Limited | Households | 1983 |
| Struan Developments Limited | Professional & scientific | 2001 |
| Structure Cladding Interaction Technology Limited | Professional & scientific | 2016 |
| STS Global Media Limited | Professional & scientific | 2019 |
| Stubborn Mule Brewery Limited | Manufacturing | 2016 |
| Student Land and Development Limited | Construction | 2010 |
| Studio 404 Development Ltd | Information & communication | 2026 |
| Studio 8 Design Ltd | Professional & scientific | 2023 |
| Studio ALT Ltd | Professional & scientific | 2021 |
| Studio Animal Limited | Arts & recreation | 2017 |
| Studio Edjo Ltd | Professional & scientific | 2010 |
| Studio Extent Limited | Professional & scientific | 2024 |
| Studio Rathi Ltd | Information & communication | 1997 |
| Studiocyren Interiors Limited | Construction | 2026 |
| Studios 1 TOS Limited | Professional & scientific | 2018 |
| Styal Beer Festival Limited | Wholesale & retail | 2025 |
| Styger Consultancy Ltd | Professional & scientific | 2014 |
| Style Barbers Limited | Other services | 2021 |
| Style Centre Limited | Wholesale & retail | 2012 |
| Styletrim Limited | Administrative & support | 2000 |
| Suave Barbers Timperely Ltd | Other services | 2026 |
| Sublime Anaesthesia Services Limited | Professional & scientific | 2023 |
| Subs IT Ltd | Information & communication | 2017 |
| Subscription & Retention Coaching Limited | Professional & scientific | 2023 |
| Subtoco UK Limited | Real estate | 2026 |
| Such Medic Limited | Health & social care | 2022 |
| Sudarshan UK SLO Ltd | Wholesale & retail | 2019 |
| Sudo Biosciences Limited | Professional & scientific | 2021 |
| SUE Thompson Limited | Professional & scientific | 2016 |
| Suffolk Road Estate Management Limited | Households | 1992 |
| Suindhyas' Oral & Facial Surgery Limited | Health & social care | 2021 |
| Sulest Limited | Professional & scientific | 2026 |
| SUM Properties Ltd | Households | 2024 |
| SUM Surveying Limited | Professional & scientific | 2021 |
| Sumitomo Electric Wiring Systems (Europe) Pensions Trust Limited | Financial services | 1989 |
| Summer Trend Limited | Wholesale & retail | 1988 |
| Summerleaze IT Consulting Limited | Professional & scientific | 2023 |
| Summertrees Property Development Ltd | Real estate | 2021 |
| Summit Planning Associates Limited | Professional & scientific | 2011 |
| Sumner Family Investments Limited | Real estate | 2025 |
| Sun Networking Limited | Professional & scientific | 2024 |
| Sun-Wa Technos (UK) Connect Solutions Ltd | Manufacturing | 1994 |
| Sunbay Education Limited | Education | 2014 |
| Suncor Energy International Trading Limited | Wholesale & retail | 2002 |
| Suncor Energy Treasury Services Limited | Financial services | 2009 |
| Suncor Energy UK Holdings Ltd | Professional & scientific | 2002 |
| Sunday App Limited | Information & communication | 2021 |
| Sunderland Regeneration LP | | 2011 |
| Sunfair Properties Limited | Real estate | 2017 |
| Sunflower Living Ltd | Real estate | 2018 |
| Sunglo Studios Ltd | Other services | 2023 |
| Sunitha Academy Ltd | Education | 2025 |
| Sunningdale Court (Sale) Management Company Limited | Households | 1977 |