| S LEA Properties Limited | Households | 2025 |
| S LEA Property Limited | Real estate | 2025 |
| S R Remedials Limited | Construction | 2013 |
| S S D a Real Estate Ltd | Real estate | 2025 |
| S Stars Childcare Ltd | Health & social care | 2024 |
| S&D Brothers Transport Ltd | Transport & logistics | 2021 |
| S&D Locksmiths Ltd | Other services | 2025 |
| S&F Partnership Limited | Other services | 2017 |
| S&K MD Limited | Health & social care | 2025 |
| S&S Properties Limited | Real estate | 2025 |
| S&W Groundworks Ltd | Construction | 2018 |
| S. Favresse Limited | Wholesale & retail | 2011 |
| S. W. Hammond Limited | Construction | 2004 |
| S.A.M. Transport & Contracting Ltd | Transport & logistics | 2025 |
| S.D.Simjee Limited | Health & social care | 2008 |
| S.E. Hamer Limited | Health & social care | 2021 |
| S.E. Trim Services Limited | Wholesale & retail | 2014 |
| S.Walsh & SON Limited | Construction | 1972 |
| SA Maddison Holdings Limited | Health & social care | 2014 |
| Sabco Packaging Ltd | Wholesale & retail | 2016 |
| Sabtopia Ltd | Wholesale & retail | 2019 |
| Sadik Barber and Nutrition Shop Limited | Other services | 2026 |
| Safar Prive Ltd | Administrative & support | 2022 |
| Safe AZ Houses Locksmith Ltd | Real estate | 2019 |
| Safe Way Lifting & Engineering Limited | Construction | 2009 |
| Safegate Limited | Extraterritorial | 2014 |
| Safety and Maintenance Services Ltd | Manufacturing | 2026 |
| Safetydeck Limited | Administrative & support | 2020 |
| Sage Reformer Studios Ltd | Arts & recreation | 2026 |
| Sage-Rms Ltd | Professional & scientific | 2017 |
| SAI Supermarket Ltd | Wholesale & retail | 2021 |
| SAI System Solutions Limited | Information & communication | 2014 |
| Sailcloth Weddings Ltd | Hospitality | 2026 |
| Saint Nicolas Limited | Information & communication | 2012 |
| Saisrita Engineering Solutions Ltd | Information & communication | 2024 |
| Saitech IT Consulting Limited | Information & communication | 2011 |
| Salah Medical Ltd | Health & social care | 2025 |
| Sales Bond Ltd | Professional & scientific | 2016 |
| Sales Loop Limited | Professional & scientific | 2023 |
| Salfordinsole Healthcare Limited | Manufacturing | 2012 |
| Sallis and Sons Limited | Construction | 2010 |
| Salon HÅR Ltd | Other services | 2024 |
| Salon Twenty Twelve Ltd | Other services | 2012 |
| Saltem Limited | Administrative & support | 2015 |
| Salutation Inn Limited | Hospitality | 2010 |
| SAM 83 Transport Ltd | Transport & logistics | 2015 |
| Samayy Ltd | Wholesale & retail | 2019 |
| Sambaff Limited | Administrative & support | 2022 |
| Sameer Palace Ltd | Hospitality | 2024 |
| Samira Spice Ltd | Hospitality | 2025 |
| Samkaur Ltd | Real estate | 2020 |
| Sammy-Jo Hair Limited | Other services | 2023 |
| Sammyjay’S Aesthetics Limited | Other services | 2025 |
| Samsee Contracts (UK) Ltd | Construction | 2013 |
| Samuel George Limited | Other services | 2004 |
| Samveda Limited | Real estate | 2022 |
| SAN Beauty Studio Ltd | Other services | 2026 |
| Sandeep Cabs Limited | Transport & logistics | 2014 |
| Sandhar Courier & Transport Ltd | Transport & logistics | 2026 |
| Sandi Heating Ltd | Construction | 2025 |
| Sandra Whiles Coaching Ltd | Professional & scientific | 2018 |
| Sanjem Ltd | Health & social care | 2019 |
| Sapphire Roofing & Home Maintenance Limited | Construction | 2025 |
| Sara Eveline Transport Limited | Transport & logistics | 2022 |
| Sarah Underwood Ltd | Other services | 2022 |
| Saru Embroidery Limited | Other services | 2017 |
| Sary&Cata Limited | Transport & logistics | 2014 |
| SAS Safal Limited | Education | 2023 |
| Satellite Industries GB Limited | Manufacturing | 1994 |
| Saunders Social Ltd | Administrative & support | 2025 |
| Savannah Grill & Lounge Ltd | Hospitality | 2026 |
| Saveway CV10 Ltd | Hospitality | 2024 |
| Savezora Properties Limited | Real estate | 2025 |
| Saxon Holdings Limited | Financial services | 2016 |
| Saxon Tool Hire Limited | Administrative & support | 2016 |
| SB Commercial Properties Ltd | Real estate | 2015 |
| Sbto Limited | Manufacturing | 2019 |
| SC Tech Services Ltd | Information & communication | 2026 |
| SC. Opex Limited | Professional & scientific | 2016 |
| Scael Limited | Professional & scientific | 2011 |
| Scale UP Platforms Limited | Information & communication | 2026 |
| Sccm Wizards Ltd | Professional & scientific | 2018 |
| Scents With Love Ltd | Manufacturing | 2021 |
| Scientists Gate Ltd | Wholesale & retail | 2025 |
| Scilead Consulting Ltd | Professional & scientific | 2025 |
| Scissorhand Barbers Ltd | Other services | 2024 |
| SCL Management Limited | Real estate | 1997 |
| Scope Aviation Ltd | Wholesale & retail | 2024 |
| Scopes Carbon Ltd | Other services | 2024 |
| Scotch Kitchen Ltd | Wholesale & retail | 2019 |
| SCS Resource Ltd | Other services | 2013 |
| SCW Power Systems Limited | Professional & scientific | 2025 |
| SDC PVT Ltd | Health & social care | 2017 |
| SDH Partnership Limited | Real estate | 2017 |
| SDP Properties Limited | Real estate | 2003 |
| SDT Cart Ltd | Arts & recreation | 2008 |
| Sdts Engineering Limited | Professional & scientific | 2017 |
| Sdts Foundry Co. Limited | Manufacturing | 2017 |
| Seaa Investments Ltd | Real estate | 2022 |
| Seagull Music Limited | Arts & recreation | 2019 |