| Sacred Stones Construction Limited | Construction | 2018 |
| Sacred Stones Hopleys Limited | Other services | 2017 |
| Sacred Stones Ltd | Other services | 2013 |
| Sacred Stones Soulton Long Barrow Limited | Other services | 2017 |
| Sacred Stones Willow ROW Ltd | Other services | 2016 |
| SAD Little Productions Ltd | Arts & recreation | 2025 |
| Saffron Compliance Limited | Professional & scientific | 2016 |
| Safsoz Properties Ltd | Real estate | 2020 |
| SAG Landscaping Ltd | Administrative & support | 2022 |
| Saker Computer Technology Limited | Information & communication | 1997 |
| Salesghost Limited | Information & communication | 2025 |
| Salon 63 Limited | Other services | 2025 |
| Samantha Andrews Ltd | Wholesale & retail | 2014 |
| Samuel's Tree Surgery Ltd | Agriculture & fishing | 2026 |
| Sandbar AP Limited | Wholesale & retail | 2004 |
| Sanders & JAY Ltd | Professional & scientific | 2018 |
| Sankey Academy Coaching Limited | Education | 2024 |
| Sankey Academy Products Limited | Arts & recreation | 2024 |
| Sankey Academy Tournaments Limited | Arts & recreation | 2024 |
| Sapien View Ltd | Information & communication | 2025 |
| Sapphire Inspection Systems Ltd | Manufacturing | 2010 |
| Saria Manzi Limited | Wholesale & retail | 2024 |
| Sarocle Limited | Professional & scientific | 2018 |
| Sartorius Stedim Chromatography Systems Ltd | Manufacturing | 2019 |
| Saunders Boston Limited | Professional & scientific | 1987 |
| Savoursmiths Limited | Manufacturing | 2010 |
| Savvy Peacocks Properties Limited | Real estate | 2022 |
| Sayush Properties Ltd | Real estate | 2020 |
| SBA Sustainability Limited | Professional & scientific | 2022 |
| SBB FOX Limited | Hospitality | 2018 |
| Sbla Solutions Limited | Professional & scientific | 2022 |
| Sbuzi Ltd | Professional & scientific | 2025 |
| SC Community Radio Ltd | Information & communication | 2026 |
| Scantlebury Farms | Agriculture & fishing | 1985 |
| Scion Instruments (UK) Ltd | Professional & scientific | 2015 |
| SCM Cambridge Ltd | Hospitality | 2021 |
| Scratching Cat Limited | Professional & scientific | 2006 |
| Scriptum EST Ltd | Professional & scientific | 2023 |
| SCS Couriers Limited | Transport & logistics | 2002 |
| Scubatx Limited | Professional & scientific | 2020 |
| Sculpted Services Ltd | Other services | 2024 |
| SCW Prop Ltd | Real estate | 2026 |
| Sdlc Services Limited | Wholesale & retail | 2003 |
| Seaport Midco Limited | Financial services | 2022 |
| Sear Securicom Limited | Administrative & support | 2009 |
| Searisk Limited | Administrative & support | 2015 |
| Securenet Communication Solutions Ltd | Information & communication | 2011 |
| Security Door Accessories Limited | Wholesale & retail | 2025 |
| Seearo Group Limited | Construction | 1997 |
| Seeing IS Believing Productions Ltd | Professional & scientific | 2019 |
| Selectability UK Ltd | Administrative & support | 2017 |
| Serendipitous Consulting Limited | Professional & scientific | 2024 |
| Sergbuild Ltd | Construction | 2025 |
| Sesko Ltd | Construction | 2014 |
| Setup (Scenery) Limited | Arts & recreation | 1998 |
| Sevran Gardens&Landscaping Ltd | Construction | 2023 |
| SFP K9 Solutions Ltd | Administrative & support | 2025 |
| SG Building and Construction Limited | Construction | 2022 |
| SG8 Design & Build Ltd | Construction | 2019 |
| SG8 Group Ltd | Arts & recreation | 2024 |
| Shabani Care Limited | Administrative & support | 2022 |
| Shaftspear Ltd | Administrative & support | 2003 |
| Shared Axis Ltd | Construction | 2026 |
| Sharma Properties 239 Ltd | Real estate | 2023 |
| Sharon Manatsa Music Limited | Arts & recreation | 2024 |
| Shawgrove Aviation Ltd | Transport & logistics | 2018 |
| Shawn White Limited | Professional & scientific | 2006 |
| Sheene Mill Retail and Therapy Limited | Other services | 2003 |
| Sheldrick Farming Limited | Agriculture & fishing | 1961 |
| Shepherd's Dream Limited | Information & communication | 2021 |
| Shepreth Wildlife Park Limited | Arts & recreation | 2014 |
| Sherratt Technical Services Limited | Administrative & support | 2007 |
| Shingay CUM Wendy Benefits Company Limited | Other services | 2014 |
| Shinwari Ltd | Wholesale & retail | 2011 |
| Shire Trees Limited | Construction | 2017 |
| Shona Wright Ltd | Information & communication | 2021 |
| Shred Corp Ltd | Arts & recreation | 2024 |
| Sibylla Genesis LLP | | 2025 |
| Sibylla Ltd | Information & communication | 2019 |
| Sifix Solutions Ltd | Construction | 2024 |
| Silfensoft Limited | Information & communication | 2011 |
| Silicon Lemonade Ltd | Information & communication | 2025 |
| Silk and Structure Ltd | Wholesale & retail | 2026 |
| Sillence Court Freehold Company Limited | Households | 2014 |
| Silly Moose Productions Ltd | Information & communication | 2024 |
| Silver Forest Properties Limited | Real estate | 2012 |
| Silveridge Financial Services Limited | Financial services | 2002 |
| Silverley Group Limited | Construction | 2016 |
| Silverley Properties Limited | Construction | 2021 |
| Silverwise Limited | Financial services | 2022 |
| Simar Variety Store Ltd | Wholesale & retail | 2025 |
| Simple Office Systematics Limited | Professional & scientific | 2002 |
| Simulco Ltd | Administrative & support | 2018 |
| Sipcam (UK) Limited | Agriculture & fishing | 1983 |
| Sipcam Home and Garden Ltd | Manufacturing | 2018 |
| Sippe Consulting Ltd | Information & communication | 2025 |
| SIX Exhibition and Events Management Limited | Professional & scientific | 2026 |
| Sixty Nine and Seventy One Gloucester Street Management Company Limited | Households | 1974 |
| SJ Wardell Consulting Limited | Professional & scientific | 2018 |
| SJM Lighting Limited | Manufacturing | 2014 |