| Shivon Sweets and Savouries Limited | Wholesale & retail | 2018 |
| Shivon Technologies Ltd | Information & communication | 2017 |
| SHO4U Limited | Transport & logistics | 2009 |
| Shoe NV Ltd | Wholesale & retail | 2022 |
| Show Machine Limited | Arts & recreation | 2014 |
| Showoff Display Limited | Administrative & support | 1995 |
| Shree Nath Traders PVT Ltd | Transport & logistics | 2024 |
| Shrewley Village Store Limited | Wholesale & retail | 2006 |
| Shri KK Homes Ltd | Real estate | 2024 |
| Shungy Ltd | Real estate | 2020 |
| SHV Energy Holdings UK Limited | Professional & scientific | 1987 |
| SHV GAS Trading Limited | Extraterritorial | 1988 |
| Sibling Winery Limited | Agriculture & fishing | 2018 |
| SIC Marking Ltd | Manufacturing | 2017 |
| Sicology Limited | Manufacturing | 2020 |
| Sidcraft Limited | Wholesale & retail | 2025 |
| Sigma Connectivity Ltd | Information & communication | 2022 |
| Signal 14 Limited | Real estate | 2025 |
| Siid Limited | Information & communication | 2019 |
| Sijoproperty Ltd | Real estate | 2022 |
| Sikh Wills Ltd | Professional & scientific | 2016 |
| Silvester Parker Limited | Professional & scientific | 2013 |
| SIM and Go Ltd | Wholesale & retail | 2024 |
| SIM2FUNDED Limited | Information & communication | 2019 |
| Simios Ltd | Professional & scientific | 2026 |
| Simmons Barn Limited | Professional & scientific | 2018 |
| Simon a Radford Limited | Education | 2014 |
| Simon Briggs Consulting Limited | Information & communication | 2014 |
| Simple Key Limited | Real estate | 2018 |
| Simple Medical Limited | Health & social care | 2025 |
| Simpleflow Consulting Limited | Professional & scientific | 2021 |
| Simplified Accountants Ltd | Professional & scientific | 2019 |
| Simply Selfbuild UK Limited | Construction | 2009 |
| Simply Wills and Trusts Limited | Administrative & support | 2007 |
| Simuly Ltd | Education | 2002 |
| Sinotel UK Limited | Wholesale & retail | 2011 |
| Siobhan Rowland Wealth Management Ltd | Financial services | 2025 |
| Sirolli Associates UK Ltd | Education | 2011 |
| Siteops Ltd | Information & communication | 2024 |
| Sixteen Beaufort Freehold Company Limited | Real estate | 2018 |
| SJ & Co Investments Ltd | Real estate | 2024 |
| SJ Duffy Limited | Construction | 2023 |
| SJ Potentialplus Ltd | Administrative & support | 2024 |
| SJA Heating & Plumbing Services Limited | Construction | 2018 |
| SJA110300 Limited | Manufacturing | 2014 |
| Sjkj Limited | Real estate | 2025 |
| Sjlcs Limited | Professional & scientific | 2008 |
| SJM Food Service Ltd | Manufacturing | 2023 |
| SJN Financial Services Limited | Financial services | 2018 |
| SK & Rays Housing Ltd | Real estate | 2025 |
| SK Enhance Ltd | Health & social care | 2020 |
| SKE Engineering Limited | Wholesale & retail | 2020 |
| Skewb Ltd | Information & communication | 2018 |
| SKI One Limited | Information & communication | 2002 |
| Skidmore Builders Limited | Construction | 2002 |
| Skintime Ltd | Health & social care | 2013 |
| SKJ Management Limited | Professional & scientific | 2024 |
| Skolon UK Ltd | Education | 2023 |
| Sksg Limited | Professional & scientific | 2026 |
| Skss Capital Ltd | Real estate | 2025 |
| Sky Club Partners Limited | Financial services | 2012 |
| Sky Corporate Accounting Services Ltd | Professional & scientific | 2015 |
| Sky Scaffolding (Midlands) Limited | Construction | 2004 |
| Skybots Construction Ltd | Construction | 2024 |
| Skybots Properties Ltd | Real estate | 2022 |
| Skyhawk Leasing Limited | Administrative & support | 1997 |
| Skyjed Limited | Information & communication | 2021 |
| Skylink Services Limited | Administrative & support | 2025 |
| SL Aesthetics Clinic Limited | Health & social care | 2025 |
| SL Hair Salon Limited | Other services | 2021 |
| Slam Software Ltd | Information & communication | 2022 |
| Sleepy Hollow Consulting Limited | Real estate | 1997 |
| Slimbound Limited | Real estate | 1969 |
| Sloan Property Enterprises Limited | Real estate | 2019 |
| Slough Motor Company Limited | Financial services | 1982 |
| SM Accountancy Services Warwickshire Limited | Professional & scientific | 2024 |
| Smallbutcool Ltd | Professional & scientific | 2015 |
| Smalley Farms Limited | Agriculture & fishing | 2002 |
| Smallman Consulting Ltd | Real estate | 2024 |
| Smart Asset Maintenance Ltd | Professional & scientific | 2019 |
| Smart Energy Services Ltd | Professional & scientific | 2024 |
| Smart Inference Ltd | Professional & scientific | 2000 |
| Smart Sound Technologies Limited | Information & communication | 2010 |
| Smartercv Limited | Professional & scientific | 2024 |
| Smartpath Data Ltd | Information & communication | 2024 |
| SME Safe Island Limited | Professional & scientific | 2023 |
| Smellyballs Limited | Wholesale & retail | 2025 |
| Smith & Pithers Financial Management Limited | Financial services | 2011 |
| Smith Maclean Group Limited | Wholesale & retail | 2021 |
| Smith Street Restaurant Ltd | Hospitality | 2025 |
| Snakecompany Limited | Real estate | 2019 |
| Snap Dog Games Ltd | Information & communication | 2025 |
| Sneed Coding Solutions Ltd | Wholesale & retail | 2020 |
| Snerfy Trading Ltd T/A Caffe Chai Warwick Limited | Hospitality | 2013 |
| SNS Social Work Limited | Health & social care | 2024 |
| SO Cocktails Limited | Hospitality | 2018 |
| SO Stay Here Ltd | Hospitality | 2020 |
| So.Blog Limited | Professional & scientific | 2019 |
| Soare Engineering Limited | Administrative & support | 2017 |
| Social Fintech Company Limited | Information & communication | 2016 |