| Safety Management Advisory Services Limited | Administrative & support | 2006 |
| Safety Vision UK Limited | Extraterritorial | 2025 |
| SAG LVM Limited | Health & social care | 2023 |
| Saglvmlife Ltd | Health & social care | 2024 |
| Sahipak Urology Limited | Health & social care | 2018 |
| SAI Suvarna Limited | Health & social care | 2023 |
| Saih Limited | Wholesale & retail | 2021 |
| Sakrit Limited | Health & social care | 2017 |
| Saks Brand Management Ltd | Wholesale & retail | 2014 |
| Saks Group (2025) Ltd | Wholesale & retail | 2025 |
| Sale Eyewear Limited | Health & social care | 2024 |
| Salespoint Limited | Administrative & support | 2001 |
| Salim Investments Ltd | Real estate | 2023 |
| Saltford Grange Limited | Health & social care | 2011 |
| SAM Pearce Design Ltd | Professional & scientific | 2026 |
| Samba Fifteen Holdings Ltd | Construction | 2024 |
| Samba Thirty One Holdings Ltd | Construction | 2024 |
| Sameena Hassan Ltd | Health & social care | 2022 |
| Samme Ltd | Professional & scientific | 2021 |
| Samsaif Law & Immigration Solutions Ltd | Professional & scientific | 2024 |
| Samtin Ltd | Wholesale & retail | 2026 |
| Samuel Booth & Company Limited | Administrative & support | 2003 |
| Sanctum Brain Health CIC | Health & social care | 2025 |
| Sanctum Consulting Limited | Professional & scientific | 2024 |
| Sanctum Healthcare Limited | Administrative & support | 2018 |
| Sanctum Peak Limited | Health & social care | 2020 |
| Sandbrook Consulting Ltd | Professional & scientific | 2024 |
| Sandco Consulting Limited | Professional & scientific | 2023 |
| Sanderling Properties Ltd | Real estate | 2013 |
| Sanders Total Health Limited | Health & social care | 2010 |
| Sandford Village (Warrington) Management Company Limited | Households | 2014 |
| Sandison Easson Limited | Professional & scientific | 2008 |
| Sandison Easson Medical Accountants Limited | Professional & scientific | 2019 |
| Sangha Medical Limited | Health & social care | 2016 |
| Sano Development Limited | Professional & scientific | 2020 |
| Sano Living Limited | Real estate | 2025 |
| Sanpedro (Buxton) Limited | Hospitality | 2023 |
| Sanpedro Holdings Limited | Financial services | 2023 |
| Santiago Restaurant and Wholesale Limited | Wholesale & retail | 2020 |
| Santis Clinic Limited | Health & social care | 2017 |
| Sapphire Strategic Communications Ltd | Professional & scientific | 2026 |
| Saracen Automation Systems Limited | Manufacturing | 2013 |
| Sarah Knight Solutions Ltd | Professional & scientific | 2023 |
| Sarah Rees Ltd | Health & social care | 2022 |
| Sarah Winthorpe Accountancy Services Limited | Professional & scientific | 2018 |
| Sarda Investment Ltd | Financial services | 2025 |
| Sarenta Care Ltd | Health & social care | 2025 |
| Sarkar Medical Limited | Health & social care | 2024 |
| Sarvam Trading Ltd | Wholesale & retail | 2018 |
| SAS Utility Management Ltd | Professional & scientific | 2024 |
| Satra Pharma Ltd | Wholesale & retail | 2023 |
| Saujana Skies Limited | Real estate | 2025 |
| Save the Planet Ltd | Professional & scientific | 2011 |
| Saville Property Developments Ltd | Real estate | 2009 |
| Saxon Manor (Tamworth) Management Company Limited | Households | 2015 |
| SBN Investments Limited | Real estate | 2021 |
| SC & VR GP Alliance Limited | Health & social care | 2014 |
| SC Life Sciences Ltd | Professional & scientific | 2019 |
| SCA Hairdressing Limited | Other services | 2013 |
| Sca&A Limited | Professional & scientific | 2019 |
| Scalloway Limited | Health & social care | 2025 |
| Scan Time Limited | Health & social care | 2013 |
| Scantech Packaging Limited | Manufacturing | 1994 |
| Scarab Ventures Limited | Health & social care | 2022 |
| Schematic Limited | Information & communication | 2024 |
| Schoolsmith Ltd | Professional & scientific | 2016 |
| Sci-U Academy Limited | Education | 2022 |
| Sci-U Body Limited | Health & social care | 2019 |
| Sci-U-Training Ltd | Education | 2024 |
| Scicomms Ltd | Professional & scientific | 2020 |
| Scientiaai Ltd | Health & social care | 2026 |
| Scope Health UK Ltd | Health & social care | 2012 |
| Scotdoc Consultancy Ltd | Health & social care | 2020 |
| Scott Hutchinson Ltd | Professional & scientific | 2023 |
| Scott Jordan Stapleton Limited | Financial services | 2022 |
| Scott Mctominay Limited | Information & communication | 2017 |
| Scribe Construction Management Services Ltd | Construction | 2024 |
| Sculptdby Ltd | Health & social care | 2025 |
| SCV Medical Limited | Health & social care | 2020 |
| SDM Incorporated Ltd | Administrative & support | 2021 |
| Sdpc (NW) Ltd | Construction | 2021 |
| Seabright Recruitment Ltd | Administrative & support | 2025 |
| Search Homes Limited | Real estate | 2025 |
| Seat Vault Limited | Administrative & support | 2026 |
| SEB Jackson Housing Limited | Real estate | 2019 |
| Sebastian James Project Solutions Ltd | Professional & scientific | 2024 |
| Secret Art Ltd | Professional & scientific | 2026 |
| Secret Holiday Retreats Limited | Real estate | 2020 |
| Secret PIE Productions Ltd | Information & communication | 2012 |
| Securipol Limited | Administrative & support | 1996 |
| Sedulus Consultants Limited | Financial services | 2016 |
| Seeit Clickit Buyit Ltd | Wholesale & retail | 2021 |
| Seiru Limited | Hospitality | 2025 |
| Select Retirement Service Limited | Real estate | 2014 |
| Self Publishing Partnership Limited | Wholesale & retail | 2015 |
| Sell Properties Ltd | Real estate | 2026 |
| Sense Corp Ltd | Administrative & support | 2023 |
| Sentinel Security Systems (North) Limited | Administrative & support | 2023 |
| Sentire AI Ltd | Information & communication | 2026 |
| Sentomax AI Limited | Information & communication | 2026 |