| Sandhu Premier Plumbing & Heating Ltd | Construction | 2026 |
| Sansa Solutions Limited | Information & communication | 2018 |
| Sante Franglais Limited | Manufacturing | 2001 |
| Santhex Trading Ltd | Wholesale & retail | 2026 |
| Sara Penrose Limited | Administrative & support | 2018 |
| Sarah Fitzgerald Consulting Ltd | Professional & scientific | 2024 |
| Satato Limited | Manufacturing | 2019 |
| Savvy UK Properties Limited | Real estate | 2020 |
| Scaldwell Investments Ltd | Professional & scientific | 2022 |
| School of Ayurveda UK Ltd | Administrative & support | 2015 |
| Schwartz & Ecclestone Ltd | Information & communication | 2023 |
| Scientis Solutions Limited | Information & communication | 2009 |
| Scott Limited | Other services | 2007 |
| SCR Control Systems Ltd | Professional & scientific | 2025 |
| Sculpt Studio Flex Ltd | Professional & scientific | 2024 |
| SD Buildworks Ltd | Construction | 2025 |
| SD Buzzard Construction Ltd | Construction | 2015 |
| SDS Trade Equipment Ltd | Wholesale & retail | 2016 |
| SDW Services Ltd | Wholesale & retail | 2025 |
| Sea Service App Ltd | Information & communication | 2025 |
| Seahawk Islanders Limited | Wholesale & retail | 2020 |
| Seamless Gutter Systems Ltd | Construction | 2019 |
| Sebire Consulting Limited | Professional & scientific | 2017 |
| Secure Management Security Group Limited | Administrative & support | 2022 |
| Seed Creativity Ltd | Professional & scientific | 2010 |
| Select Catering Solutions Limited | Manufacturing | 2008 |
| Select Living Group Ltd | Administrative & support | 2016 |
| Selennia Ltd | Professional & scientific | 2021 |
| Self Awareness School Limited | Professional & scientific | 2022 |
| Selfmate Limited | Wholesale & retail | 2017 |
| SEM Acquisitions Limited | Real estate | 2019 |
| Send Shoot Send Ltd | Information & communication | 2023 |
| Sentimental Journey Limited | Education | 2019 |
| Seriously Hampers Ltd | Wholesale & retail | 2022 |
| Serpocurst Ltd | Administrative & support | 2024 |
| Serviced Holdings Limited | Financial services | 2024 |
| Seven Bridges IM Ltd | Professional & scientific | 2014 |
| SF Projects Limited | Professional & scientific | 2025 |
| Sfrc Ltd | Professional & scientific | 2017 |
| SG Electrical Market Harborough Ltd | Construction | 2016 |
| SGS Woodworking Solutions Limited | Construction | 2008 |
| Shade TEN Ltd | Professional & scientific | 2024 |
| Shagorika Indian Restaurant Ltd | Hospitality | 2024 |
| Shanying WAN Ltd | Health & social care | 2019 |
| Sharman Avionics Limited | Manufacturing | 2007 |
| Sharman Grange Ltd | Real estate | 2022 |
| Sharpboddy Limited | Hospitality | 2022 |
| Sharpe Langham Limited | Extraterritorial | 1997 |
| Sheer Edge Ltd | Administrative & support | 2012 |
| Sheldrake Systems Consultancy Limited | Information & communication | 2015 |
| Shelton’S Outdoor Services Ltd | Administrative & support | 2022 |
| SHH Management Limited | Administrative & support | 2012 |
| Shine Marketing and Communications Limited | Professional & scientific | 2018 |
| Shire Press Ltd | Manufacturing | 2008 |
| Shire Surveyors Limited | Real estate | 2013 |
| Shoulder of Mutton Management Ltd | Hospitality | 2026 |
| Shrives-Wright Ltd | Administrative & support | 2010 |
| Shuvert Limited | Real estate | 2022 |
| Sibbertoft Manor Coach House Ltd | Health & social care | 2025 |
| Siddhartha Bhowmick Ltd | Health & social care | 2025 |
| Sidkorx Ltd | Administrative & support | 2024 |
| Sielia Limited | Professional & scientific | 2021 |
| Sienna G Group Ltd | Professional & scientific | 2025 |
| Sierra Delta Aerospace UK Ltd | Professional & scientific | 2023 |
| Siesta Cuisine Ltd | Hospitality | 2020 |
| Signature Exclusive Gifts Limited | Administrative & support | 2011 |
| Silver Access Ltd | Professional & scientific | 2015 |
| Silverline Surveyors Ltd | Professional & scientific | 2022 |
| Simergy Consulting Limited | Transport & logistics | 2015 |
| Simon a Barton Limited | Professional & scientific | 2012 |
| Simplicity Timber Solutions Ltd | Manufacturing | 2012 |
| Simply Cider Ltd | Manufacturing | 2018 |
| Simply Plants Limited | Other services | 2016 |
| Singlehurst Mcsp Ltd | Health & social care | 2010 |
| Sinotech Limited | Administrative & support | 2008 |
| Siott Ltd | Arts & recreation | 2010 |
| Sipos Estates Limited | Real estate | 2025 |
| Sircle of Ideas & Culture Ltd | Information & communication | 2022 |
| SIT and Sleep (Derby) Limited | Wholesale & retail | 1987 |
| Situational Solutions Ltd | Public administration | 2018 |
| Size Consulting Limited | Professional & scientific | 2022 |
| SJ & HJ Holdings Limited | Financial services | 2019 |
| SJW Auto Tuning and Repairs Limited | Wholesale & retail | 2013 |
| SK (Northampton ) Limited | Hospitality | 2024 |
| Skala.Rl Ltd | Professional & scientific | 2024 |
| Skills and Employment Support Limited | Professional & scientific | 2014 |
| Sky Vertex Limited | Real estate | 2026 |
| Sladey's Sports Lounge Ltd | Hospitality | 2026 |
| SLR Consultancy Ltd | Professional & scientific | 2009 |
| Smart (MH) Limited | Professional & scientific | 2020 |
| Smart Banq Technologies Ltd | Financial services | 2021 |
| Smart Interiors (UK) Limited | Wholesale & retail | 2005 |
| Smart-Cover Direct Limited | Financial services | 2013 |
| Smart-Sure Ltd | Financial services | 2011 |
| Smart-Telecom Ltd | Financial services | 2010 |
| SMC Display & Exhibition Systems Limited | Construction | 2010 |
| SMC Maintenance Ltd | Other services | 2018 |
| Smith Power Ltd | Construction | 2020 |
| Smith Property Services Limited | Real estate | 2020 |
| SML Stunts Ltd | Education | 2024 |