| SCS Certification Europe Ltd | Professional & scientific | 2026 |
| Sculpt and Shine Wellness Ltd | Other services | 2025 |
| Sculpt Body Ltd | Wholesale & retail | 2024 |
| SD Griffin Ltd | Financial services | 2025 |
| SDA Legal Limited | Professional & scientific | 2015 |
| SDH Solutions Limited | Information & communication | 2001 |
| SE Murphy Limited | Professional & scientific | 2008 |
| Sea INK Ltd | Health & social care | 2025 |
| Sea Ridge (Westcliff) Estates Limited | Real estate | 1977 |
| Sea Wind Properties Limited | Real estate | 1999 |
| Seahorse Recording Studio Limited | Arts & recreation | 2005 |
| Sealand Manor Energy Centre Limited | Energy | 2022 |
| Sealed Aromas Ltd | Wholesale & retail | 2025 |
| Sealtite Sealants Limited | Construction | 1989 |
| Searchtd Ltd | Information & communication | 2016 |
| Searings Motor Cycles (1988) Limited | Wholesale & retail | 1988 |
| Searings Properties Limited | Construction | 2001 |
| Searle Accountancy Services Limited | Professional & scientific | 2005 |
| Seasonhaul Limited | Wholesale & retail | 2025 |
| Seasons Trading Limited | Wholesale & retail | 2025 |
| Sebago Limited | Wholesale & retail | 1994 |
| Sebtraffic Services Ltd | Public administration | 2022 |
| SEC Installations Limited | Construction | 2006 |
| Second Bullwood Estate Company Limited | Real estate | 1955 |
| Second Hendon Property Company Limited(The) | Real estate | 1959 |
| Secret Africain Ltd | Professional & scientific | 2026 |
| Secret Garden 452 Limited | Hospitality | 2018 |
| Secret Lilac Limited | Wholesale & retail | 2021 |
| Secure Skills Academy Ltd | Administrative & support | 2024 |
| Secure Tech Juris Ltd | Information & communication | 2026 |
| Secured Solutionist Ltd Ltd | Professional & scientific | 2023 |
| Securely Limited | Financial services | 2025 |
| Securetech Installations Ltd | Administrative & support | 2006 |
| Security Data Limited | Information & communication | 1989 |
| Sedrans Intercontinental | | 2007 |
| Seedat Properties Limited | Real estate | 1994 |
| Seedventure Limited | Financial services | 2022 |
| Seen Ventures Limited | Real estate | 2015 |
| Seetec Business Technology Centre Limited | Education | 1988 |
| Sefrex Limited | Hospitality | 1994 |
| Segrave & Partners (Essex) Limited | Extraterritorial | 1994 |
| Sehaj Reality Ltd | Real estate | 2023 |
| Sejoc Auto Repairs Limited | Wholesale & retail | 2003 |
| Sekin Ltd | Hospitality | 2023 |
| Selacha Ltd | Wholesale & retail | 2026 |
| Selcuk ARI Ltd | Wholesale & retail | 2024 |
| Select Catering Fabrications Limited | Manufacturing | 2007 |
| Select Lift Services Limited | Construction | 2005 |
| Select Signs (Clacton) Ltd | Professional & scientific | 2004 |
| Selex ES (Projects) Ltd | Public administration | 2006 |
| Selfina Ltd | Wholesale & retail | 2025 |
| Sell USD Ltd | Financial services | 2025 |
| Sellens Engineering Ltd | Wholesale & retail | 2000 |
| Sellio Limited | Wholesale & retail | 2026 |
| Sellquik Limited | Wholesale & retail | 2003 |
| Sellvion Ltd | Wholesale & retail | 2026 |
| Selms Muir Energy Centre Limited | Energy | 2019 |
| Selva Barbers Ltd | Other services | 2023 |
| Sembeh Associate Limited | Professional & scientific | 2014 |
| Semigrocers Hub Limited | Wholesale & retail | 2025 |
| Sems Real Estates LLP | | 2018 |
| SEN Bytes Ltd | Education | 2024 |
| Senate Consultancy and Solutions Limited | Information & communication | 2003 |
| Senior Leader Mentoring Limited | Administrative & support | 2005 |
| Sentain Consulting Limited | Professional & scientific | 2002 |
| Serandro Solutions Ltd | Transport & logistics | 2022 |
| Seriosity Ltd | Construction | 2025 |
| Servdirect Limited | Professional & scientific | 2006 |
| Servebrook Limited | Wholesale & retail | 1981 |
| Serverbike Ltd | Information & communication | 2022 |
| Serviceman Franchise PLC | | 1985 |
| Servrite Plumbing & Building Supplies Limited | Wholesale & retail | 2012 |
| SES Group Limited | Administrative & support | 1997 |
| SES Mechanical Services Limited | Professional & scientific | 2000 |
| Seshat Logic LAB Ltd | Information & communication | 2026 |
| SET Interiors Limited | Construction | 2019 |
| Setform Projects Ltd | Construction | 2004 |
| Seth Medical Ltd | Health & social care | 2015 |
| Sevar Limited | Real estate | 2003 |
| Sevendec Consulting Limited | Professional & scientific | 2004 |
| Seventeen Property Ventures Limited | Real estate | 2021 |
| Seventh Day Church of GOD (Reformed) | Other services | 2006 |
| SEW Devine Limited | Professional & scientific | 2000 |
| Shaan Properties Ltd | Real estate | 2002 |
| Shaara Limited | Real estate | 2003 |
| Shahab Holdings Ltd | Wholesale & retail | 2026 |
| Shahjahan Trading Limited | Professional & scientific | 2007 |
| Shaikh & Associates Ltd | Hospitality | 2024 |
| Shajr& Co Ltd | Real estate | 2023 |
| Shakespeare Engineering International Limited | Manufacturing | 2003 |
| Shamrock Guesthouse Ltd | Hospitality | 2003 |
| Shanga Lulu Ltd | Wholesale & retail | 2025 |
| Shanka Engineering Limited | Professional & scientific | 2017 |
| Share Speak Limited | Real estate | 2000 |
| Shark Chauffeurs Limited | Transport & logistics | 2023 |
| Sharp Sports Ltd | Wholesale & retail | 2026 |
| Sharptruth | Other services | 2016 |
| Sharry Services Limited | Real estate | 2006 |
| Shatri Centre Ltd | Education | 2014 |
| Shaw & Associates (Accounting Services) Limited | Professional & scientific | 1997 |