| Skippy's Retail Wholesale Ltd | Wholesale & retail | 2012 |
| SKV Expert Ltd | Construction | 2024 |
| Skyline Arcomet Limited | Construction | 2004 |
| Skyline Design & Build Ltd | Construction | 2024 |
| SL Accountancy Ltd | Professional & scientific | 2008 |
| SL Infratech Solutions UK Ltd | Information & communication | 2025 |
| Slavatradeshop Ltd | Wholesale & retail | 2025 |
| Slimeboard Ltd | Wholesale & retail | 2026 |
| Sliqktouchevents Limited | Wholesale & retail | 2023 |
| SMA Technology and Gadget Limited | Wholesale & retail | 2026 |
| Small Acorn Ideas Limited | Arts & recreation | 2007 |
| Smart & Grace Healthcare Ltd | Health & social care | 2018 |
| Smart Removal and Logistics Limited | Water & waste | 2026 |
| Smash & Shakez Ltd | Hospitality | 2026 |
| Smash Wave Ltd | Hospitality | 2026 |
| Smgs Building Services Ltd | Construction | 2022 |
| SMH Training & Staffing Ltd | Professional & scientific | 2014 |
| Smith & Sons Property Group Limited | Real estate | 2023 |
| Smith Bailey and Anderson Limited | Manufacturing | 1982 |
| Smithsonite Estates Ltd | Real estate | 2022 |
| SMS Property Developers Ltd | Construction | 2023 |
| Snacktivate Limited | Manufacturing | 2025 |
| Snapjobs Ltd | Administrative & support | 2025 |
| Snasa Limited | Transport & logistics | 2024 |
| Softee Bros Limited | Hospitality | 2025 |
| Soho Decor Studio Ltd | Professional & scientific | 2024 |
| SOK Investments Ltd | Real estate | 2023 |
| SOK Project Ltd | Construction | 2015 |
| Solid & Secure Construction Ltd | Construction | 2019 |
| Solidrock Exports Ltd | Transport & logistics | 2020 |
| Solucity Health Care Limited | Health & social care | 2019 |
| Somsak Ltd | Information & communication | 2025 |
| Sotade Limited | Real estate | 2025 |
| South Rainham Take Away Ltd | Hospitality | 2022 |
| Southern Properties Investments Ltd | Real estate | 2024 |
| SP Capital Holdings Limited | Real estate | 2025 |
| Spark & Shield Trading Ltd | Wholesale & retail | 2025 |
| Sparkle Maids Ltd | Administrative & support | 2022 |
| Sparkright Electrical Limited | Construction | 2009 |
| Special Security Services Limited | Administrative & support | 2025 |
| Spectrum Bridges Ltd | Manufacturing | 2025 |
| Speedy Store Ltd | Wholesale & retail | 2025 |
| Spirits Express Ltd | Wholesale & retail | 2025 |
| Spot on Scaffold Limited | Construction | 2023 |
| Springlets Limited | Real estate | 2021 |
| Springvale Driveways Limited | Construction | 2015 |
| Squad Solutions Ltd | Construction | 2013 |
| SR Wines Limited | Wholesale & retail | 2019 |
| Sriradu Ltd | Wholesale & retail | 2020 |
| Srirama Technologies Ltd | Information & communication | 2026 |
| Srsg Engineering Ltd | Professional & scientific | 2024 |
| SS & T Estates Limited | Real estate | 2023 |
| SS Simple Solutions Limited | Construction | 2021 |
| Ssanz Ltd | Real estate | 2023 |
| SSP Leak Detection Ltd | Administrative & support | 2016 |
| ST Alban’S Baby & Toddler CIC | Health & social care | 2023 |
| ST Enterprise Online Ltd | Real estate | 2020 |
| Stafhold Healthcare Limited | Administrative & support | 2022 |
| Stalwart Holdings Ltd | Professional & scientific | 2008 |
| Standard Technologies Ltd | Manufacturing | 2025 |
| Stanford Tackle Centre Limited | Wholesale & retail | 2022 |
| Star Disposables Limited | Wholesale & retail | 2010 |
| Star Lite Support Services Limited | Administrative & support | 2014 |
| Star Packing Ltd | Wholesale & retail | 2024 |
| Star Ways Tiling Ltd | Administrative & support | 2016 |
| Starfix Limited | Construction | 2013 |
| Starling Capital Ltd | Wholesale & retail | 2026 |
| Starlings Preschool Limited | Education | 2024 |
| Staska Limited | Wholesale & retail | 2020 |
| Status Motor Group Ltd | Wholesale & retail | 2024 |
| Steam Futures CIC | Education | 2026 |
| Steel Beams Ltd | Manufacturing | 2009 |
| Stefana Construction Ltd | Construction | 2019 |
| Stellafoam Limited | Wholesale & retail | 1960 |
| Sterling Born Assets Limited | Real estate | 2021 |
| Sterling Establishment Ltd | Health & social care | 2025 |
| Sterling Europe Ltd | Administrative & support | 2010 |
| Sterling Hype Ltd | Health & social care | 2026 |
| Sterling Motor Capital Ltd | Professional & scientific | 2026 |
| Sterling Sustainable Development Group Ltd | Construction | 2019 |
| STN Property Management Services Limited | Real estate | 2024 |
| Stone & Porcelain Distribution Limited | Wholesale & retail | 2024 |
| Stone FOX Financial Services Ltd | Financial services | 2021 |
| Stratitec Limited | Information & communication | 2014 |
| Stratnet Consulting Limited | Information & communication | 2025 |
| Stratos Ventures Limited | Wholesale & retail | 2024 |
| Stream Care Services Limited | Health & social care | 2023 |
| Strideforge Ltd | Wholesale & retail | 2026 |
| Studio Refit Team Ltd | Construction | 2024 |
| Studioyears Limited | Professional & scientific | 2022 |
| Suavitas Ltd | Public administration | 2024 |
| Subhan Enterprises Limited | Financial services | 2024 |
| Sudn Trading Services Limited | Wholesale & retail | 2017 |
| Sueno Private Limited | Health & social care | 2022 |
| Sukh Estates Ltd | Real estate | 2019 |
| Sultanate Services Ltd | Administrative & support | 2022 |
| Sunderland Investments Ltd | Real estate | 2024 |
| Sunny's Minimarket Ltd | Wholesale & retail | 2016 |
| Sunrise Pipeline Limited | Information & communication | 2026 |
| Sunrise UK Services Ltd | Other services | 2016 |