| Shepley Investments,Limited | Professional & scientific | 1922 |
| Shepley Securities Limited | Extraterritorial | 1966 |
| Sheriff Railway,Highway Ltd | Construction | 2015 |
| Shezi Tech Limited | Information & communication | 2024 |
| Shield Care Solutions Ltd. | Health & social care | 2023 |
| Shield Roofing and Construction Ltd | Construction | 2025 |
| Shiloh PR Limited | Professional & scientific | 2011 |
| Shimmer Cleaning Ltd | Administrative & support | 2023 |
| Shinaben Ltd | Health & social care | 2025 |
| Shineemo Ltd | Transport & logistics | 2022 |
| Shinly Limited | Hospitality | 2026 |
| Shiplu Enterprise UK Ltd | Hospitality | 2020 |
| Shipshape Maintenance Ltd | Construction | 2025 |
| Shiro Services UK Limited | Construction | 2025 |
| Shivago Food Ltd | Hospitality | 2021 |
| Shivago Ltd | Wholesale & retail | 2018 |
| Shiyana's Properties Ltd | Real estate | 2023 |
| Shobail Ltd | Health & social care | 2010 |
| Shogun Academy of Martial Arts Limited | Arts & recreation | 2014 |
| Shoni Travels Ltd | Transport & logistics | 2026 |
| Shopbargain Ltd | Wholesale & retail | 2026 |
| Shopnexify Limited | Wholesale & retail | 2025 |
| Shopulence Limited | Wholesale & retail | 2021 |
| Shopulence Wholesale Ltd | Wholesale & retail | 2021 |
| Shree Images Ltd | Information & communication | 2016 |
| Shri Maruti Nivaas Limited | Real estate | 2025 |
| Shyam Limited | Real estate | 2021 |
| Sian Lewis Consulting Ltd | Professional & scientific | 2024 |
| Siaw Properties Ltd | Real estate | 2026 |
| Siba Investments Limited | Real estate | 2026 |
| Sibuya Limited | Financial services | 2012 |
| SID & Aish Enterprise Ltd | Wholesale & retail | 2022 |
| Sidhu & Sons Property Ltd | Real estate | 2024 |
| Sightseeingo Ltd | Administrative & support | 2021 |
| Sigma Property Developers Limited | Real estate | 2022 |
| Sigma Wholesale Ltd | Wholesale & retail | 2017 |
| Sign Holdings Limited | Professional & scientific | 1988 |
| Signature Care Ltd | Health & social care | 2023 |
| Signature Refurbishments Ltd | Construction | 2026 |
| Signature Touch Property Services Ltd | Administrative & support | 2026 |
| Silvavine Limited | Education | 2024 |
| Silvea Ltd | Wholesale & retail | 2025 |
| Silver Foxes Ltd | Other services | 2009 |
| Silver Serve Ltd | Transport & logistics | 2015 |
| Silvera Meam Ltd | Professional & scientific | 2019 |
| Silverclean Limited | Administrative & support | 2018 |
| Silverlining Solutions Ltd | Transport & logistics | 2026 |
| Sima Plastics Limited | Extraterritorial | 1974 |
| Simactors Limited | Education | 2016 |
| Simon & Co Event Catering Limited | Hospitality | 2025 |
| Simple BUT NOT Simpler Ltd | Professional & scientific | 2022 |
| Simplified Staffing Limited | Health & social care | 2018 |
| Simply Learn Driving School Limited | Education | 2020 |
| Simply Luxury Ltd | Administrative & support | 2020 |
| Simply Property Investors Limited | Information & communication | 2008 |
| Sindu Catering Ltd | Manufacturing | 2024 |
| Sintl Construct Ltd | Construction | 2024 |
| Sintl Investments Ltd | Real estate | 2010 |
| Sintl Ltd | Construction | 2006 |
| Sintl Ventures Ltd | Administrative & support | 2021 |
| Sipan Limited | Professional & scientific | 2012 |
| Sirfrank Properties Ltd | Real estate | 2026 |
| Siru Enterprises Ltd | Wholesale & retail | 2025 |
| Siskony Ltd | Construction | 2015 |
| Sita London Limited | Real estate | 2017 |
| Siteng Ltd | Construction | 2016 |
| Siteseen Limited | Information & communication | 2007 |
| SK Dental Services Ltd | Health & social care | 2019 |
| SK Imperial Ltd | Information & communication | 2022 |
| SK JV Group Ltd | Real estate | 2023 |
| SKG Accountant Ltd | Professional & scientific | 2023 |
| Skinthetica Ltd | Other services | 2025 |
| SKJ Property Services Ltd | Real estate | 2022 |
| SKR Care Services Incorporated Limited | Health & social care | 2023 |
| Skripta Education Ltd | Education | 2025 |
| Skulaunch Ltd | Information & communication | 2025 |
| Sky Sash Windows Ltd | Manufacturing | 2005 |
| Sky Vault Security Ltd | Administrative & support | 2024 |
| Skyblu Foundation Limited | Other services | 2014 |
| Skyblue Intelligent Systems Limited | Information & communication | 2007 |
| Skybridge Solutions Limited | Real estate | 2025 |
| Skye Scaffolding (London) Limited | Construction | 2015 |
| Skylight Depo Ltd | Wholesale & retail | 2024 |
| Skylineautos Ltd | Wholesale & retail | 2023 |
| Skymaster Travel & Tourism Limited | Administrative & support | 2026 |
| Skyn Clinic by Rabs Ltd | Other services | 2025 |
| Skyrock Developments Limited | Construction | 2025 |
| Skyzars Limited | Wholesale & retail | 2024 |
| Sleepify Limited | Wholesale & retail | 2022 |
| Slice of Bliss Ltd | Manufacturing | 2019 |
| Slightly Minty Ltd | Information & communication | 2018 |
| Sloley Direct Marketing Ltd | Hospitality | 2025 |
| Sls-Tp Ltd | Transport & logistics | 2025 |
| Slucy Media Ltd | Professional & scientific | 2023 |
| SMA Autotech Ltd | Wholesale & retail | 2023 |
| Smaa Properties Limited | Wholesale & retail | 2024 |
| Smart Bookkeepers Ltd | Professional & scientific | 2023 |
| Smart Glaze P&B Limited | Construction | 2012 |
| Smart Green Solutions Ltd | Professional & scientific | 2024 |
| Smart House Building Services Ltd | Construction | 2024 |