| Samson House Limited | Extraterritorial | 1987 |
| Samwoo UK Ltd | Wholesale & retail | 2021 |
| Sam’S Doggy Hotel and Spa Ltd | Other services | 2023 |
| Sana Bana Limited | Hospitality | 2012 |
| Sanctuary Found Ltd | Manufacturing | 2021 |
| Sanctuary Play Cafe Limited | Arts & recreation | 2025 |
| Sanctus Property Group Ltd | Real estate | 2023 |
| Sandle Construction Services Ltd | | 2010 |
| Sandons Limited | Extraterritorial | 2009 |
| Sandown Construction Ltd | Construction | 2025 |
| Sands Project Group Limited | Wholesale & retail | 2023 |
| Sansom Site Services Ltd | Construction | 2023 |
| Sansom Tech Limited | Wholesale & retail | 2019 |
| Sapr London Ltd | Construction | 2015 |
| Saracen Motor Group Ltd | Wholesale & retail | 2021 |
| Saromi Limited | Real estate | 1998 |
| Saskia Solutions Ltd | Information & communication | 2021 |
| Sassybear Ltd | Real estate | 2024 |
| Sauna Services Limited | Administrative & support | 2019 |
| Saving Energy Limited | Other services | 2007 |
| Sawong Property Ventures Ltd | Real estate | 2017 |
| SB Landscaping and Patios Ltd | Construction | 2026 |
| SB Trees and Patios Ltd | Construction | 2026 |
| SBP Media Ltd | Administrative & support | 2008 |
| SBZ Chemicals Ltd | Manufacturing | 2023 |
| SBZ Corporation Limited | Manufacturing | 2003 |
| SBZ Equine Ltd | Arts & recreation | 2021 |
| SBZ Group Ltd | Financial services | 2024 |
| SBZ Holdings Limited | Real estate | 2015 |
| SBZ Supply and Trading Ltd | Financial services | 2024 |
| SC Home Improvements & Maintenance Ltd | Construction | 2026 |
| SC Medical Services Ltd | Health & social care | 2023 |
| Scarlett Energy Limited | Wholesale & retail | 2002 |
| Scary Frog Limited | Information & communication | 2018 |
| Scentl Ltd | Wholesale & retail | 2025 |
| Schofield, SON & Daughter Limited | Other services | 2018 |
| Sciens Consulting Limited | Professional & scientific | 2021 |
| SCM Electrical Contractors Ltd | Construction | 2023 |
| Scott Moody Consulting Ltd | Construction | 2019 |
| Scrap My Car NOW Ltd | Wholesale & retail | 2025 |
| SDS Partners LLP | | 2019 |
| SDS Specialist Facades Holdings Limited | Construction | 2023 |
| SDS Specialist Facades Limited | Construction | 2023 |
| Seafood AK Limited | Hospitality | 2025 |
| Seaford Grange (Newlands) Management Company Limited | Real estate | 2020 |
| Seamingly Perfect Prints Ltd | Manufacturing | 2025 |
| Seamore Developments & Properties Ltd | Construction | 2023 |
| Searos Limited | Information & communication | 2010 |
| Seaview Consultants Limited | Professional & scientific | 2020 |
| Seaview Television Ltd. | Manufacturing | 2002 |
| Secometric Limited | Professional & scientific | 1947 |
| Second Used Japanese Cars Limited | Wholesale & retail | 2024 |
| Secondhand Alloys Limited | Wholesale & retail | 2009 |
| Secure Self Storage (Prittlewell) Limited | Administrative & support | 2019 |
| Secure Self Storage Limited | Administrative & support | 2008 |
| SED Commercial Ltd | Construction | 2021 |
| Seemore Glass Conservatories Ltd | Construction | 2022 |
| Seemore Glass Limited | Construction | 2010 |
| Seemore Glass W&D Ltd | Construction | 2022 |
| Seijeje Limited | Health & social care | 2014 |
| Sela Educational Initiatives Limited | Information & communication | 2010 |
| Select Scaffolding Ltd | Construction | 2017 |
| Sempiternity Pictures Limited | Information & communication | 2006 |
| SEN Ltd | Wholesale & retail | 2021 |
| Sendtguard Limited | Administrative & support | 2021 |
| Sentinel Power Solutions Limited | Construction | 2026 |
| Sequensis Planning Limited | Professional & scientific | 2011 |
| Serati Limited | Other services | 2021 |
| Service Flame Ltd | Construction | 2014 |
| Services SA Ltd | Wholesale & retail | 2018 |
| Servicies SA Group Ltd | Wholesale & retail | 2024 |
| Servo Group South Ltd | Administrative & support | 2022 |
| Session Tackle Ltd | Wholesale & retail | 2020 |
| SET for the Show Ltd | Arts & recreation | 2026 |
| SGC Glass Ltd | Construction | 2003 |
| SGD Homes Ltd | Real estate | 2023 |
| SH Health & Fitness Ltd | Arts & recreation | 2019 |
| Shahay Management Limited | Professional & scientific | 2020 |
| Shapes N Curls Ltd | Other services | 2002 |
| Share Space Eleven Limited | Administrative & support | 2025 |
| Sharp Space Limited | Construction | 2022 |
| Sharp Teeth Limited | Information & communication | 2022 |
| Shelter Essex Roofing Ltd | Construction | 2025 |
| Sheraton Systems Limited | Information & communication | 1989 |
| Shield Ventures Limited | Administrative & support | 2003 |
| Shinra Electrical Installations Ltd | Construction | 2025 |
| Shore Scaffolding Limited | Construction | 1999 |
| Shot Farm Limited | Arts & recreation | 2009 |
| Shotgate Convenience Stores Ltd | Wholesale & retail | 2023 |
| Shotgate Technical Solutions Ltd | Professional & scientific | 2025 |
| Shree Aadinath Properties Ltd | Real estate | 2025 |
| Shree Shakthi Ltd | Wholesale & retail | 2020 |
| Shunet Limited | Administrative & support | 2014 |
| Shutters by James Ltd | Construction | 2020 |
| Shutterstrip Concrete Solutions Ltd | Construction | 2020 |
| Sido Solutions Ltd | Other services | 2014 |
| Silicon Milk Roundabout Ltd | Administrative & support | 2016 |
| Silt Pigz UK Ltd | Wholesale & retail | 2024 |
| Silver Edge Studios Ltd | Information & communication | 2018 |
| Silver Taverns Ltd | Hospitality | 2024 |