| Smartconsent Ltd | Information & communication | 2023 |
| Smarter Drainage Ltd | Other services | 2021 |
| Smarter Finance Limited | Financial services | 2022 |
| Smarter Savings Partnership Ltd | Professional & scientific | 2024 |
| Smash Wings Co Ltd | Hospitality | 2025 |
| SME Classics Limited | Wholesale & retail | 2017 |
| SMF Building Contractors Ltd | Construction | 2024 |
| SMG Associates Ltd | Professional & scientific | 2025 |
| Smile High Ballooning Ltd | Transport & logistics | 2014 |
| Smile of Wight Ltd | Manufacturing | 2017 |
| Smilemaker Healthcare Limited | Administrative & support | 2016 |
| Smith & Burgess Limited | Professional & scientific | 2024 |
| Smithco Marketing Limited | Information & communication | 2023 |
| Smithfest Holdings Limited | Professional & scientific | 2020 |
| Smiths Cctv Contractors Ltd | Administrative & support | 2005 |
| SNA Commodities Limited | Wholesale & retail | 2010 |
| Snapbubble Limited | Information & communication | 2009 |
| Snapgate Consulting Limited | Professional & scientific | 2019 |
| Snappyscran Limited | Information & communication | 2025 |
| Sncl Associates Ltd | Construction | 2015 |
| Snow Retreat Limited | Administrative & support | 2006 |
| Snowear Limited | Wholesale & retail | 2008 |
| SNS Accountants Ltd | Professional & scientific | 2024 |
| Social Housing Construction Lawyer Ltd | Administrative & support | 2017 |
| Social-Ability Limited | Health & social care | 2019 |
| Soditic Asset Management LLP | | 2008 |
| Soditic Limited | Financial services | 1995 |
| Soil Biology Holdings Ltd | Financial services | 2022 |
| Soil Biology Limited | Wholesale & retail | 2016 |
| Sojo International Partners Limited | Wholesale & retail | 1960 |
| Solace Publishing Ltd | Manufacturing | 2024 |
| Solar Flair Group Ltd | Construction | 2025 |
| Solaris Group Ltd | Real estate | 2021 |
| Solcv Limited | Financial services | 2002 |
| Soleil Health Ltd | Health & social care | 2022 |
| Solens Consultants Limited | Professional & scientific | 2000 |
| Solent Music Festival | Arts & recreation | 2012 |
| Solidant Limited | Construction | 2014 |
| Sollinetec Limited | Information & communication | 2025 |
| Solterbeck Consulting Limited | Information & communication | 2026 |
| Soltyoneuk Ltd. | Real estate | 2024 |
| Solve Able Ltd | Information & communication | 2023 |
| Somerhill Charitable Trust Limited | Education | 1988 |
| Songhurst Building Solutions Ltd | Construction | 2016 |
| Sonitus Group Limited | Professional & scientific | 2019 |
| Sonitus Home Limited | Professional & scientific | 2019 |
| Sonny's Hand Car Wash Ltd | Wholesale & retail | 2020 |
| Sonohealth Ltd | Health & social care | 2021 |
| Soper Transport Ltd | Administrative & support | 2025 |
| Sophia Point Rainforest Project | Extraterritorial | 2020 |
| SOS Consult Limited | Professional & scientific | 2014 |
| Sound Communities Consulting Limited | Professional & scientific | 2026 |
| South Audley Securities Limited | Real estate | 1990 |
| South Coast Camhs Limited | Health & social care | 2017 |
| South Coast Diagnostics LLP | | 2015 |
| South Downs Butchery Ltd | Wholesale & retail | 2020 |
| South East Building Contractors Limited | Construction | 2003 |
| South East Conservation Limited | Construction | 2014 |
| South East Flat Roofing Ltd | Construction | 2018 |
| South East Mezzanine Limited | Administrative & support | 2009 |
| South East Mortgage Solutions Limited | Administrative & support | 2016 |
| South East Partitioning Limited | Administrative & support | 2002 |
| South East Resin and Paving Ltd | Construction | 2024 |
| South East TEN Ltd | Hospitality | 2015 |
| South East TEN Trading Limited | Real estate | 2010 |
| South East Veterinary Referrals Limited | Professional & scientific | 2024 |
| South East Vision and Imaging Limited | Health & social care | 2018 |
| South Eastern Beers & Minerals Limited | Wholesale & retail | 1994 |
| South London Dermatology & Radiology Experts Ltd | Health & social care | 2016 |
| South London Makers Ltd | Professional & scientific | 2006 |
| South of England Hotel Services (1946) Limited | Real estate | 1946 |
| Southborough Consultancy Services Ltd | Professional & scientific | 2014 |
| Southeast Construction Contractors Ltd | Construction | 2024 |
| Southern Asbestos Services Limited | Construction | 1986 |
| Southern Care Maintenance Limited | Administrative & support | 1988 |
| Southern Counties Training Services Ltd | Education | 2003 |
| Southern County Care Group Ltd | Administrative & support | 2005 |
| Southern County Care Ltd | Administrative & support | 2017 |
| Southern Doors Ltd | Manufacturing | 2024 |
| Southern Membranes (Single PLY) Ltd | Construction | 2021 |
| Southern Office Furniture Ltd | Wholesale & retail | 1996 |
| Southern Plumbing Drainage & Water UK Limited | Financial services | 2020 |
| Southern Plumbing Drainage Assist Ltd | Construction | 2025 |
| Southfield Road Limited | Households | 2006 |
| Southside Residents (Management) Limited | Households | 1999 |
| Sovereign Way Cleaners Ltd | Administrative & support | 2023 |
| SP 3D Solutions Ltd | Professional & scientific | 2025 |
| Spa Close Management Limited | Professional & scientific | 1999 |
| Spa Scaffolding Services (South) Ltd | Construction | 2025 |
| Spacelight Electrical Ltd | Construction | 2023 |
| Spacemid Property Management Limited | Households | 1989 |
| Spareroom Architecture Ltd | Professional & scientific | 2024 |
| Spark Advertising Group Limited | Professional & scientific | 2023 |
| Sparta SPV 2 Ltd | Real estate | 2023 |
| Spartan Adventures Limited | Administrative & support | 2012 |
| Spartatech Limited | Wholesale & retail | 2013 |
| Speak to Engage Limited | Education | 2018 |
| Specified Performance Ltd | Wholesale & retail | 2023 |
| Spectacular Optical Productions Ltd | Information & communication | 2018 |
| Spectra Medical Limited | Health & social care | 2014 |