| Save Your Bacon Ltd | Hospitality | 2014 |
| Savoury Selections Limited | Wholesale & retail | 2024 |
| Saxon Online Ltd | Wholesale & retail | 2021 |
| SBC Development Services Limited | Information & communication | 2019 |
| SBM Financial Services Limited | Education | 2003 |
| SBM Services (UK) Limited | Professional & scientific | 2013 |
| SBR E&I Services Ltd | Construction | 2022 |
| SC3 Solutions Limited | Information & communication | 2004 |
| Scale++ Ltd | Information & communication | 2024 |
| Scarlet River Brewing Company Ltd | Manufacturing | 2021 |
| Schememajor Limited | Real estate | 1991 |
| School ICT Group Limited | Financial services | 2019 |
| School ICT Services Ltd | Information & communication | 2009 |
| Scielutions Limited | Wholesale & retail | 2012 |
| Scientific Engineering Systems Ltd. | Information & communication | 2015 |
| Scientific Indaba Ltd | Professional & scientific | 2021 |
| Scion Publishing Limited | Wholesale & retail | 2003 |
| Scootees Ltd | Wholesale & retail | 2024 |
| Screentech Limited | Wholesale & retail | 2003 |
| Scudding Clouds Limited | Construction | 2016 |
| Sdmb Limited | Information & communication | 2010 |
| Seaforth Management Ltd | Professional & scientific | 2015 |
| Seahorse Textile Care Specialists Limited | Other services | 2011 |
| Search Intelligence Ltd | Information & communication | 2014 |
| Seaton Business Consulting Ltd | Professional & scientific | 2025 |
| Seatspy Limited | Transport & logistics | 2019 |
| Seba Trade Limited | Wholesale & retail | 2017 |
| Second-Hand Darkroom Supplies Limited | Wholesale & retail | 2011 |
| Secor Ltd | Information & communication | 2020 |
| Secret Japan Travel Limited | Administrative & support | 2025 |
| Sector Skills Limited | Education | 2025 |
| Secure Storage Solutions Limited | Administrative & support | 2024 |
| Securiplug Ltd | Manufacturing | 2019 |
| Seefin Consulting Limited | Professional & scientific | 2021 |
| Selene Design Ltd | Information & communication | 2012 |
| Self Build Joinery Solutions Limited | Extraterritorial | 2015 |
| Self Storage 4 YOU Ltd | Transport & logistics | 2023 |
| Selo Catering Limited | Hospitality | 2023 |
| Selpins Ltd | Hospitality | 2025 |
| Senclude Limited | Education | 2009 |
| Send My Box Ltd | Transport & logistics | 2019 |
| Sensory Waves Ltd | Wholesale & retail | 2025 |
| Sentinel Investigations Ltd | Administrative & support | 2024 |
| Seredon Care Ltd | Administrative & support | 2014 |
| Serendib Global Foods Limited | Wholesale & retail | 2007 |
| Serendib Shipping & Finance Ltd | Transport & logistics | 2011 |
| Serenisis Ltd | Health & social care | 2022 |
| Serox Limited | Professional & scientific | 2015 |
| Service Metrology Limited | Professional & scientific | 2018 |
| Sessile Limited | Wholesale & retail | 2024 |
| SEVENTY6 Scaffold Hire & Sales Ltd | Financial services | 2019 |
| Seymour Advisory Services LLP | | 2019 |
| SF Davies Construction Limited | Construction | 2020 |
| SGH Holdings Ltd | Financial services | 2026 |
| SGJ Bloombridge (IOW) Limited | Other services | 2017 |
| SGO Foods Ltd | Hospitality | 2022 |
| SH Decor Ltd | Construction | 2011 |
| Shadelogik Ltd | Professional & scientific | 2022 |
| Shadowfleet-Rentals Ltd | Administrative & support | 2025 |
| Shair Collective Ltd | Administrative & support | 2023 |
| Shape Machining Ltd | Manufacturing | 2014 |
| Shaun Rowland Building Contractors Limited | Construction | 2001 |
| Sheep Street Limited | Real estate | 2026 |
| Sheepdog Enterprises Limited | Real estate | 2006 |
| Sheldons Yurts Ltd | Other services | 2019 |
| Sherard Veasey Advisory Limited | Professional & scientific | 2026 |
| Sherchan PVT. Limited | Hospitality | 2017 |
| Sherwin-Williams UK Limited | Manufacturing | 1994 |
| Shield Maiden Productions Ltd | Information & communication | 2024 |
| Shields Longden Limited | Professional & scientific | 2022 |
| Shields Property Development Limited | Real estate | 2025 |
| Shilton Properties Limited | Real estate | 2022 |
| Shine & Tidy Co. Limited | Administrative & support | 2025 |
| Shires Bespoke Carpentry & Construction Ltd | Manufacturing | 2020 |
| Shog Construction Ltd | Construction | 2011 |
| Shooting Movies Limited | Information & communication | 2008 |
| Shoppercentric Limited | Professional & scientific | 2004 |
| Shortheath Limited | Construction | 2017 |
| Shredding Made Simple Limited | Administrative & support | 2019 |
| Shun & JEY Limited | Wholesale & retail | 2022 |
| Siblings Hairdressing Limited | Other services | 2018 |
| Sierra Global Ltd | Wholesale & retail | 2021 |
| Signal EQ Ltd | Professional & scientific | 2026 |
| Signature Packaging Online Ltd | Wholesale & retail | 2026 |
| Signifo Ltd | Information & communication | 2000 |
| Signs and Fleet Ltd | Wholesale & retail | 2018 |
| Signum Esot Limited | Extraterritorial | 1997 |
| Signum Technologies Limited | Information & communication | 1997 |
| Silva Bullet Limited | Arts & recreation | 2022 |
| SIM Drive Five Ltd | Manufacturing | 2024 |
| Simmonds & Sons Limited | Construction | 2015 |
| Simon Ana-Maria Limited | Health & social care | 2019 |
| Simon Bennett Associates Ltd | Professional & scientific | 2010 |
| Simon Keane Ltd | Professional & scientific | 2019 |
| Simon Mackrory Ltd | Construction | 2006 |
| Simon White Services Limited | Real estate | 2017 |
| Simon William Millar Ltd | Professional & scientific | 2025 |
| Simplee Ceramics Ltd | Health & social care | 2010 |
| Simply Nepal Limited | Administrative & support | 2019 |
| SIMPLYFOODS2GO Ltd | Extraterritorial | 2014 |