| SB Morgan Group Limited | Professional & scientific | 2026 |
| SBI Management Consultancy Limited | Administrative & support | 2026 |
| Sbmac Limited | Hospitality | 2023 |
| Scanners Inc | Arts & recreation | 2018 |
| Scanwing Limited | Construction | 1994 |
| Scarfs / Ties & Others Limited | Wholesale & retail | 2023 |
| School of Natural Therapies (Clapham) Limited | Education | 2020 |
| SCM Refurbishment Ltd | Construction | 2023 |
| SD Motors Limited | Wholesale & retail | 2012 |
| Sdlc Software Solutions Limited | Information & communication | 2010 |
| Sea Fish Limited | Hospitality | 2013 |
| SEA-7 Services Ltd. | Professional & scientific | 2014 |
| Seaway Shipping and Tourist Services Ltd | Transport & logistics | 2025 |
| Secma Ltd | Wholesale & retail | 2018 |
| Securitytek Ltd | Administrative & support | 2025 |
| Sedulous Drivers Ltd | Transport & logistics | 2020 |
| Selecta Properties Investment Limited | Administrative & support | 1991 |
| Selhurst Community Sports Arena C.I.C. | Arts & recreation | 2014 |
| Senior Tech (UK) Limited | Information & communication | 2007 |
| Sense IT Solutions Ltd | Information & communication | 2023 |
| Sentech Groups Ltd | Information & communication | 2024 |
| Senthil Tech Ltd | Information & communication | 2024 |
| Seriously Sourced Ltd | Administrative & support | 2025 |
| Serveiq Group Ltd | Administrative & support | 2025 |
| SEU Trading Ltd | Wholesale & retail | 2026 |
| SEV Trading Group Ltd | Financial services | 2025 |
| Sevely Ltd | Wholesale & retail | 2025 |
| Sgcbogachan Ltd | Other services | 2024 |
| SGH Automotive Services Ltd | Wholesale & retail | 2019 |
| SGH Properties Croydon Ltd | Real estate | 2026 |
| SGS Fabrication Ltd | Manufacturing | 2024 |
| Shah Homes and Holdings Ltd | Real estate | 2026 |
| Shahi Mughal Darbar Limited | Hospitality | 2026 |
| Shakes Therapy Ltd | Hospitality | 2025 |
| Shakti Property Limited | Real estate | 2021 |
| Shamgar Ltd | Wholesale & retail | 2023 |
| Shao Capital Limited | Wholesale & retail | 2026 |
| Shashees Limited | Information & communication | 2025 |
| Shawa Security Limited | Administrative & support | 2015 |
| Sheenverse Limited | Wholesale & retail | 2024 |
| Shensha Enterprises Ltd | Wholesale & retail | 2024 |
| Shift Pro Limited | Transport & logistics | 2025 |
| Shimul Trading UK Ltd | Information & communication | 2019 |
| Shina Building Solutions Ltd | Construction | 2022 |
| Shine Bright Speaking Limited | Professional & scientific | 2020 |
| Shining Stars Nursery London Ltd | Health & social care | 2026 |
| Shiny Wheels Limited | Transport & logistics | 2018 |
| Shiv Events Limited | Hospitality | 2013 |
| Shopeno Limited | Wholesale & retail | 2025 |
| Shopora Hub Limited | Wholesale & retail | 2025 |
| Shopping One Stop Co Ltd | Administrative & support | 2025 |
| Shortt Circuits Electrical Ltd | Professional & scientific | 2020 |
| Shree Gayatri Homes Ltd | Real estate | 2022 |
| Shree Sidhi Ltd | Wholesale & retail | 2025 |
| Shriyank Trading Ltd | Wholesale & retail | 2026 |
| Shubh London Ltd | Manufacturing | 2020 |
| Shubz Property Holding Limited | Real estate | 2026 |
| Shzw Estates Ltd | Real estate | 2022 |
| Sibelane Ltd | Wholesale & retail | 2025 |
| Sibley's Social Research Ltd | Professional & scientific | 2024 |
| SIC IT Consultancy Services Ltd | Information & communication | 2023 |
| Sierra Engineering Ltd | Professional & scientific | 2024 |
| SIGMAMART01 Limited | Wholesale & retail | 2025 |
| Siimba's Ltd | Professional & scientific | 2020 |
| Sikura Limited | Information & communication | 2026 |
| Silver Aura Ltd | Wholesale & retail | 2024 |
| Silver Lining Stays Ltd | Real estate | 2025 |
| Silverleigh House Ltd | Real estate | 2019 |
| Silverleigh Insights Ltd | Information & communication | 2025 |
| SIM Building Services Ltd | Construction | 2016 |
| Siminstal&Repair Limited | Construction | 2023 |
| Simmonds Group Limited | Transport & logistics | 2018 |
| Simmsfix Ltd | Construction | 2025 |
| Simone Olagoke Enterprises Ltd | Education | 2020 |
| Simple Business Limited | Health & social care | 2023 |
| Simply Makarios Limited | Health & social care | 2022 |
| Simply Retail 24/7 Limited | Wholesale & retail | 2026 |
| Sims Home Kitchen Ltd | Information & communication | 2022 |
| Sindh Automation Limited | Wholesale & retail | 2014 |
| Singh & Niazi Investment Limited | Wholesale & retail | 2023 |
| Singh Renovations Ltd | Construction | 2021 |
| Sirkap Digital Ltd | Professional & scientific | 2018 |
| Sisa Realty Ltd | Real estate | 2025 |
| SISTER2SISTER Creations Ltd | Wholesale & retail | 2025 |
| Siya Events Global Limited | Administrative & support | 2019 |
| SJB Property 1 Ltd | Real estate | 2026 |
| SK Associate Lettings Ltd | Real estate | 2021 |
| Skiaskin Ltd | Wholesale & retail | 2022 |
| Skilled Manpower Ltd | Information & communication | 2022 |
| Skint Gang Ltd | Professional & scientific | 2022 |
| SKJ Property Investment Limited | Real estate | 2020 |
| Skne Limited | Wholesale & retail | 2016 |
| SKS Transportation Services UK Ltd | Transport & logistics | 2025 |
| SKT Builders Ltd | Construction | 2020 |
| SKT Electrical Fixing Ltd | Construction | 2026 |
| SKT Properties Management Ltd | Construction | 2024 |
| Sky 11 Investments Limited | Financial services | 2026 |
| Sky Shortcuts Ltd | Administrative & support | 2025 |
| Sky White London Limited | Other services | 2024 |
| Skyline Maintenance Ltd | Administrative & support | 2026 |