| Starr (Wimbledon) Limited | Wholesale & retail | 1956 |
| Starr B Cars Ltd | Wholesale & retail | 2025 |
| Start Productions Limited | Information & communication | 2003 |
| Startestsmk Ltd | Administrative & support | 2025 |
| Starwood Care Services Ltd | Health & social care | 2023 |
| Statera Estates Management Ltd | Hospitality | 2025 |
| Staticguard Ltd | Other services | 2002 |
| Station Garage (Loughton) Limited | Construction | 1959 |
| Statom Tower Crane Holdings Limited | Financial services | 2023 |
| Steadech Apex Investments and Development Ltd | Construction | 2025 |
| Steady Trading Limited | Transport & logistics | 1986 |
| Stealpricelux Limited | Wholesale & retail | 2024 |
| Steel and Rose Ltd | Wholesale & retail | 2026 |
| Steel Connection Limited | Manufacturing | 2012 |
| Stellar Projects Ltd | Professional & scientific | 2019 |
| Stepchange Associates Limited | Professional & scientific | 2004 |
| Stephen Philips Limited | Wholesale & retail | 1990 |
| Stephen-Lambert Southern Limited | | 1964 |
| Stephvaness Intermediate Services Limited | Health & social care | 2020 |
| Sterling Bricks Ltd | Real estate | 2025 |
| Sterling Corporate Advisory Ltd | Professional & scientific | 2024 |
| Sterling Culture Media Co Ltd | Wholesale & retail | 2025 |
| Sterling Looms Limited | Wholesale & retail | 2025 |
| Sterling Newmedia Ltd | Information & communication | 2004 |
| Sterling Parts Limited | Professional & scientific | 2003 |
| Sterling Properties & Management Ltd | Real estate | 2021 |
| Sterling Wealth Partners Ltd | Real estate | 2016 |
| Sterling Workforce Solutions Limited | Administrative & support | 2025 |
| Steve Bird Groundworks Limited | Construction | 2000 |
| Steve Morris Contracts Limited | Construction | 2000 |
| Steve Mott & Co. Limited | Wholesale & retail | 2001 |
| Steve Smedley Carpet Planning Limited | Wholesale & retail | 2006 |
| Stewards Desk Limited | Professional & scientific | 2025 |
| Steyson Granolithic Contractors Limited | Construction | 1969 |
| Stidrat Associates Limited | Arts & recreation | 2004 |
| Stitchsnest Limited | Wholesale & retail | 2025 |
| Stocking Pelham Energy Centre Limited | Energy | 2020 |
| Stockurities Limited | Real estate | 1954 |
| Stockwell Centre (Colchester) Limited(The) | Health & social care | 1979 |
| Stockwell Motor Accessories Limited | Wholesale & retail | 1959 |
| Stockwell Motor Factors Limited | Construction | 1961 |
| Stoketree Limited | | 1982 |
| Stone Builders UK Limited | Other services | 2008 |
| Stone Mortgage Solutions Limited | Financial services | 2019 |
| Stonebridge Audit Limited | Extraterritorial | 2007 |
| Stonebridge Group Limited | Professional & scientific | 2007 |
| Stonebridge Tax Limited | Extraterritorial | 2007 |
| Stonebridge Waste Management Ltd | Water & waste | 2025 |
| Stonegold Limited | Other services | 1996 |
| Stoneleaf Building Materials Limited | Administrative & support | 1999 |
| Stonewood East Ltd | Construction | 2006 |
| Stord LAB Limited | Information & communication | 2021 |
| Store A-Z Ltd | Manufacturing | 2005 |
| Stormproof Roofing Company Limited | | 1988 |
| Stortford Tiling & Marble Ltd | Manufacturing | 2009 |
| Stow Court Management Company Limited | Real estate | 2004 |
| Stow Financial Services Ltd | Administrative & support | 2022 |
| Stowe Consulting Limited | Financial services | 2003 |
| Strada Cleaning Company Ltd | Administrative & support | 2000 |
| Stradbroke Commercial Ltd | Real estate | 2023 |
| Stradbroke Village Limited | Real estate | 2018 |
| Straitshill Enterprises Limited | Administrative & support | 2005 |
| Strategic Breaks Limited | Real estate | 1996 |
| Strategic IT Partnership Ltd | Information & communication | 2007 |
| Stratford (High Street) Limited | Construction | 2003 |
| Strathmore Care Limited | Extraterritorial | 2004 |
| Stratton Place Management Limited | Real estate | 1976 |
| Stratton Place Properties Limited | Real estate | 1996 |
| Streamberry Construction Limited | | 1977 |
| Streamz Ventures Ltd | Administrative & support | 2024 |
| Street Quads Limited | Wholesale & retail | 2003 |
| Streets Consulting Limited | Professional & scientific | 2007 |
| Strenson Group Ltd | Real estate | 2023 |
| Stressless Nights Ltd | Hospitality | 2024 |
| Strive Express Solutions Ltd | Transport & logistics | 2026 |
| Striveology Limited | Information & communication | 2026 |
| Strong Sciences Limited | Professional & scientific | 2019 |
| Stuart Phillips Ltd. | Real estate | 1994 |
| Studio B Records Limited | Wholesale & retail | 2026 |
| Studio Florists Ltd | Wholesale & retail | 2007 |
| Studio Homes Limited | Information & communication | 1991 |
| Studio X Designs Ltd | Wholesale & retail | 2006 |
| Studylinks Solutions Ltd | Professional & scientific | 2021 |
| Stylmo Limited | Information & communication | 2025 |
| Stysz Ltd | Wholesale & retail | 2026 |
| SU Global Limited | Real estate | 2020 |
| Subtlemarket Limited | Wholesale & retail | 2025 |
| Succeed in Spain Limited | Professional & scientific | 2003 |
| Sugar Wholesale Limited | Transport & logistics | 1992 |
| Suger Rush Ltd | Wholesale & retail | 2023 |
| Suha Store Ltd | Wholesale & retail | 2025 |
| Sukjinder Chana Limited | Real estate | 2024 |
| SULACO426 Ltd | Professional & scientific | 2022 |
| Sulaiman Ltd | Administrative & support | 2018 |
| Sulmat Ltd | Wholesale & retail | 2026 |
| Sultan's Enterprises Ltd | Wholesale & retail | 2024 |
| Summerby Services Limited | Construction | 2004 |
| Summerlee Gardens Limited | Real estate | 1996 |
| Summitlid Ltd | Wholesale & retail | 2025 |
| Sumnshop Ltd | Wholesale & retail | 2025 |