| Sameday Sprint Dispatch Courier Services Ltd | Transport & logistics | 2024 |
| Samsareen Limited | Real estate | 2019 |
| Sarah's Catering Limited | Hospitality | 2003 |
| SBX Advisers Limited | Professional & scientific | 2026 |
| Scalpel Limited | Manufacturing | 2017 |
| Scientia Investments Ltd | Construction | 2023 |
| SCL Electrical & Certification Ltd | Construction | 2021 |
| Scorpion Motors (Southern) Limited | Wholesale & retail | 2021 |
| Scudi UK Limited | Extraterritorial | 2022 |
| SD OIL & GAS Consulting Ltd | Other services | 2017 |
| Sean Bone Marketing Ltd | Information & communication | 2020 |
| Securinex LLP | | 2023 |
| Self Love Mastery Ltd | Education | 2021 |
| Sems Fairlight LLP | | 2017 |
| Serota Limited | Construction | 2003 |
| Service Cool Limited | Energy | 2014 |
| Shortform Ltd | Information & communication | 2017 |
| Shugi Group Limited | Financial services | 2024 |
| Shugi Medicare Ltd | Health & social care | 2011 |
| SIE Anthony Ltd | Administrative & support | 2017 |
| Silver Pallas Limited | Financial services | 2024 |
| Silvermist Properties (Residential Developments) Limited | Real estate | 1959 |
| Simon Matthew & Co Limited | Professional & scientific | 1986 |
| Simpson Raine Limited | Construction | 1989 |
| SJ Upton Farm Trustees NO.1 Limited | Administrative & support | 2020 |
| SJ Upton Farm Trustees NO.2 Limited | Administrative & support | 2020 |
| SJB Consultancy Group Ltd | Professional & scientific | 2024 |
| SJM Health Solutions Limited | Health & social care | 2026 |
| Slda Holdings Limited | Transport & logistics | 2020 |
| SM Resinas Ltd | Manufacturing | 2024 |
| Smart Polymers Ltd | Manufacturing | 2021 |
| Smart Solar Energy Ltd | Construction | 2022 |
| SMJ Childcare Ltd | Health & social care | 2018 |
| SMJ Properties and Investments Ltd | Real estate | 2025 |
| Smudge Media Studio Limited | Information & communication | 2008 |
| Sncb Investments Ltd | Construction | 2025 |
| SNJ Auto Electrics Ltd | Manufacturing | 2012 |
| Socentric Software Limited | Professional & scientific | 2006 |
| Solea Homes Limited | Construction | 2026 |
| Sondrix Limited | Administrative & support | 2025 |
| Song Chuan Precision UK Ltd | Wholesale & retail | 2017 |
| Sound Contracts Limited | Professional & scientific | 2022 |
| South Dock Limited | Professional & scientific | 2023 |
| South East Property Developers II Limited | Construction | 2016 |
| South East Property Developers Limited | Construction | 2015 |
| Spark & Co UK Ltd | Construction | 2024 |
| Spring Farm Development Limited | Construction | 2023 |
| Springfield Tiptree Management Company Limited | Real estate | 2020 |
| SPS Asset Holdings Limited | Financial services | 2011 |
| SRB Property Management Ltd | Real estate | 2017 |
| SRB Property Services Ltd | Construction | 2016 |
| SRM Wealth Management Ltd | Financial services | 2014 |
| SRS Enabling & Demolition Limited | Construction | 2015 |
| SRX Construction Limited | Construction | 2026 |
| Ssgm Investments Limited | Professional & scientific | 2015 |
| Stance Sets Limited | Construction | 2021 |
| Stanton Hale Limited | Education | 2008 |
| Stargazing Consulting Limited | Professional & scientific | 2025 |
| Staroak Care Services Ltd | Health & social care | 2026 |
| STAY24 Bookings Referrals Limited | Real estate | 2025 |
| STAY24 Holdings Limited | Financial services | 2025 |
| STAY24 Management Limited | Real estate | 2025 |
| STAY24 Rent to Rent Limited | Real estate | 2025 |
| Stephen Asher Consulting Limited | Professional & scientific | 2004 |
| Stephenson Farming Ltd | Agriculture & fishing | 2012 |
| Steve Nuding Hairdressing Limited | Other services | 2016 |
| Stirling Bond Enterprises Limited | Other services | 2000 |
| Stoa Foundation | Arts & recreation | 2025 |
| Stoa Projects Ltd | Other services | 2025 |
| Stock 4X4 Ltd | Wholesale & retail | 2023 |
| Stock Dogs Ltd | Agriculture & fishing | 2024 |
| Stock Harvard Consulting Limited | Professional & scientific | 2019 |
| Stock Pre-School | Education | 2008 |
| Stockdogs Hotel Ltd | Agriculture & fishing | 2024 |
| Storage Aspects Ltd | Administrative & support | 2016 |
| Strangford Properties Ltd | Real estate | 2020 |
| Strategic Shift Ltd | Information & communication | 2023 |
| Stratosvir Limited | Professional & scientific | 2020 |
| Streamadvice Limited | Real estate | 2003 |
| Sumac UK Limited | Information & communication | 2002 |
| Sun Glitter Ltd | Information & communication | 2017 |
| Sunrex Construction (UK) Ltd | Construction | 2000 |
| Sunview Rooflights Ltd | Wholesale & retail | 2018 |
| Sustainable Drain Solutions Ltd | Water & waste | 2026 |
| Suzal Limited | Financial services | 2021 |
| SW Locums Ltd | Administrative & support | 2009 |
| Swal Engineering Ltd | Professional & scientific | 2021 |
| Swoop Taxis Ltd | Information & communication | 2006 |
| T J Civil Engineering Ltd | Construction | 2011 |
| T J Civil Management Limited | Construction | 2014 |
| T Watts Farms Limited | Agriculture & fishing | 2018 |
| T. Elliott Landrovers Limited | Wholesale & retail | 2017 |
| T.I.P Trading Limited | Agriculture & fishing | 2024 |
| Talentkind Ltd | Administrative & support | 2025 |
| Talis Group Holdings Ltd | Financial services | 2019 |
| Talis Property Ltd | Real estate | 2018 |
| Tamh Clinical Psychology Ltd | Health & social care | 2026 |
| TAN Y Pistyll Limited | Hospitality | 2025 |
| Tathra Ltd | Information & communication | 2014 |
| Tatli Tahmini Limited | Professional & scientific | 2015 |