| Shree Ganesh Feast India Ltd | Wholesale & retail | 2025 |
| Shreeanadi Limited | Real estate | 2015 |
| Shreeanadi Property LLP | | 2025 |
| Shrinkpro Limited | Manufacturing | 2011 |
| Shrubhill Farms Limited | Agriculture & fishing | 2006 |
| Si-Jet Limited | Manufacturing | 1980 |
| Siant Creative Ltd | Construction | 2023 |
| Sibbers Trucking Solutions Ltd | Transport & logistics | 2023 |
| Sibson Marina Limited | Administrative & support | 2005 |
| SID Technical Services Limited | Professional & scientific | 2018 |
| Sidham Estates Limited | Real estate | 2010 |
| Sidney RAY Properties Limited | Real estate | 2024 |
| Sidney RAY Services Limited | Professional & scientific | 2024 |
| SIG Contractors Ltd | Construction | 2012 |
| Sigma Communications Limited | Other services | 2021 |
| Sigma Fuel Trading Ltd | Wholesale & retail | 2019 |
| Signature Land (Thame) Ltd | Construction | 2024 |
| Signworld Screen Printers Limited | Manufacturing | 1987 |
| Silbury 364 Limited | Financial services | 2007 |
| Sillavan Anodes Limited | Extraterritorial | 1975 |
| Sillavan Industries Limited | Extraterritorial | 1984 |
| Silva Swann Sealants Limited | Construction | 2026 |
| Silver Edge Developments Limited | Construction | 2021 |
| Silver Edge Homes Limited | Households | 2021 |
| Silver Edge Limited | Financial services | 2021 |
| Silver Edge Property Limited | Financial services | 2021 |
| Silver JET Insight Ltd | Professional & scientific | 2015 |
| Silver Star Property Solutions Ltd | Real estate | 2026 |
| Silver Star Taxis Limited | Transport & logistics | 2018 |
| Silverdisc Holdings Limited | Financial services | 2021 |
| Silverdisc Limited | Information & communication | 1993 |
| Silverrosecleaningservices Ltd | Administrative & support | 2025 |
| Silverstreams Innovation Ltd | Information & communication | 2024 |
| Silvr DM Limited | Information & communication | 2019 |
| Simark IT Limited | Professional & scientific | 2018 |
| Simmax Healthcare Services Ltd. | Health & social care | 2015 |
| Simon & Co Lettings Limited | Real estate | 2018 |
| Simon Coles Brickwork Limited | Construction | 2005 |
| Simon Laskey Ltd | Professional & scientific | 2021 |
| Simon Musto Estates Limited | Real estate | 2003 |
| Simon Transport Ltd | Transport & logistics | 2024 |
| Simon Wisdom Limited | Professional & scientific | 2016 |
| Simply A2B Limited | Extraterritorial | 2009 |
| Simply Spotless Cleaning Solutions Ltd | Administrative & support | 2025 |
| Simpson MK Limited | Construction | 2017 |
| Simpsons Property Experts Limited | Real estate | 2023 |
| Simuka Resources Limited | Information & communication | 2014 |
| Sinaji Ltd | Information & communication | 2022 |
| Sinclair Alexander Limited | Professional & scientific | 2022 |
| Sinevia Ltd | Information & communication | 2012 |
| Singh Singh & Singh Purchasing Limited | Real estate | 2016 |
| SIR Cosmetics Ltd | Wholesale & retail | 2007 |
| SIT and Sonder Ltd | Information & communication | 2023 |
| Sitec Services Ltd | Wholesale & retail | 2022 |
| Sitowen Limited | Real estate | 2025 |
| SIX Spheres Limited | Health & social care | 2015 |
| Size Seven Holdings Limited | Financial services | 2026 |
| Size Seven Law Limited | Professional & scientific | 2022 |
| Size Seven Sports Limited | Arts & recreation | 2024 |
| SJ Bulk Transport Limited | Transport & logistics | 2013 |
| SJ Midlands Limited | Wholesale & retail | 2016 |
| SJ Pegg Services Ltd | Other services | 2018 |
| SJC Systems Ltd | Information & communication | 1997 |
| SJE Haulage Limited | Transport & logistics | 2023 |
| SJE Tradings Ltd | Transport & logistics | 2026 |
| SJN Mechanical Management Ltd | Construction | 2025 |
| SJP Engineering Services Limited | Administrative & support | 2016 |
| SJS Graphics Ltd | Manufacturing | 2023 |
| Sjsr Property Limited | Real estate | 2024 |
| SJT Consultancy Ltd | Information & communication | 2025 |
| SK Accountancy Limited | Professional & scientific | 2015 |
| SK Investments & Developments Limited | Real estate | 2024 |
| Skalr Marketing Ltd | Professional & scientific | 2026 |
| SKC Trading Limited | Wholesale & retail | 2015 |
| Sketch Construction Limited | Construction | 2025 |
| Skin by Jadore Ltd | Other services | 2024 |
| Skin United Ltd | Information & communication | 2024 |
| Skinz Automotive Ltd | Wholesale & retail | 2024 |
| SKIRTS2CEILINGS Cleaning Limited | Administrative & support | 2020 |
| SKS Fitness Ltd | Extraterritorial | 2019 |
| Sky FAR Ltd | Wholesale & retail | 2025 |
| Skybasics Ltd | Water & waste | 2015 |
| Skybleu Research Ltd | Education | 2010 |
| Skyshoppers Limited | Wholesale & retail | 2020 |
| SL Gaming Consoles Ltd | Wholesale & retail | 2025 |
| SL Leak Plumbing Ltd | Construction | 2025 |
| Slabhaus Limited | Construction | 2018 |
| Slade Limited | Financial services | 1991 |
| Slade Tech Limited | Information & communication | 2019 |
| SLC Structural Ltd | Construction | 2023 |
| SLK Proservices Ltd | Construction | 2022 |
| Sllim Property Management Ltd | Real estate | 2025 |
| SLM Contractors Limited | Construction | 2006 |
| SLM Plant Limited | Construction | 2013 |
| Sloanes Hair & Beauty Limited | Other services | 2003 |
| SM Sylhet Limited | Hospitality | 2018 |
| Sm.Prime Ltd | Construction | 2023 |
| Small Car World Ltd | Wholesale & retail | 2010 |
| Smallwood & Sons Ltd | Real estate | 2019 |
| Smart Automotive Refurbishment Limited | Administrative & support | 2016 |