| S(Up)Port IBC Limited | Other services | 2024 |
| S. Diggens Building Services Ltd | Construction | 2023 |
| S.G.R. Beheer IBC Limited | Other services | 2020 |
| S.G.Sandford Limited | Wholesale & retail | 1955 |
| Sabre Surveying Ltd | Professional & scientific | 2016 |
| Sagitta Market Research Limited | Professional & scientific | 1999 |
| Sahara Vencera LP | | 2016 |
| Saharnify Limited | Other services | 2025 |
| SAIGO21 Ltd | Information & communication | 2023 |
| Salemnify Limited | Other services | 2025 |
| Saltwind Limited | Information & communication | 2023 |
| Saltwood Care Centre Ltd | Health & social care | 2002 |
| Salus Employment Limited | Other services | 2020 |
| Samson Plumbing Heating and Electrical Ltd | Construction | 2023 |
| Sandgate Community Trust Limited | Health & social care | 2010 |
| Sandgate Deli Limited | Hospitality | 2023 |
| Sandtiles Distributors (Hampshire) Limited | Real estate | 1972 |
| Sandy Villas Limited | Real estate | 2019 |
| Sapremacy Beheer Limited | Other services | 2025 |
| Sapremacy Limited | Other services | 2025 |
| Saya Invest Limited | Professional & scientific | 2012 |
| Schildersbedrijf Reinders B.V. Limited | Other services | 2025 |
| Schildersbedrijf Reinders Beheer B.V. Limited | Other services | 2025 |
| Seabrook Management Ltd | Households | 2019 |
| Seabrook Studio Ltd | Professional & scientific | 2021 |
| Securemybooking.Com Limited | Extraterritorial | 2007 |
| Securemyreservation.Com Limited | Financial services | 2007 |
| Securemyticket.Com Limited | Financial services | 2007 |
| Sentium Group Ltd | Financial services | 2022 |
| Sentium Technologies Ltd | Information & communication | 2020 |
| SET Padel Limited | Arts & recreation | 2021 |
| Seven Park Road Kent Limited | Other services | 2022 |
| SGR International Holding Limited | Other services | 2020 |
| Shepherds Auto Drive Maintenance Limited | Households | 2019 |
| Shepway Estate Ltd | Construction | 2012 |
| Shields Decorators Limited | Construction | 1999 |
| Shipway House Garden Company Limited | Administrative & support | 2018 |
| Shipway House Management Company Limited | Real estate | 2019 |
| Shiva Holding Limited | Professional & scientific | 2019 |
| Shivkrishna Dagverzorging Limited | Professional & scientific | 2013 |
| Shorenham Limited | Professional & scientific | 2009 |
| SHS Developments Ltd | Households | 2025 |
| Silver Mountain Holding Limited | Professional & scientific | 2017 |
| Silverleaf Care Homes Limited | Health & social care | 2010 |
| Simmering Shots Ibiza Limited | Professional & scientific | 2019 |
| Simmering Shots Limited | Professional & scientific | 2012 |
| Singing for Dementia Limited | Health & social care | 2011 |
| Siti Services Ltd | Transport & logistics | 2026 |
| Sitzpinkler Finance Corporation Limited | Professional & scientific | 2018 |
| Sivaruby Convenience Store Limited | Wholesale & retail | 2025 |
| SJR PM Solutions Limited | Information & communication | 2014 |
| Skyline Lifts Ltd | Professional & scientific | 2024 |
| Skymero Limited | Other services | 2024 |
| SLC Capital Ltd | Construction | 2025 |
| SLR Hythe Ltd | Wholesale & retail | 2025 |
| SM Smart Repairs Ltd | Wholesale & retail | 2023 |
| Smart Brokerage International Limited | Transport & logistics | 2021 |
| Smart Fishing UK Ltd | Arts & recreation | 2020 |
| Smart PD Limited | Education | 2012 |
| Smart Support Ltd | Professional & scientific | 2012 |
| Smartgo Europe Beheer Limited | Other services | 2025 |
| Smartgo Europe Limited | Other services | 2025 |
| SMH Support Limited | Other services | 2025 |
| Smh-Support Holding Limited | Other services | 2025 |
| Smugglers Mews Management Company Ltd | Households | 2017 |
| Snapdragon Medical Communications Ltd | Professional & scientific | 2026 |
| SNB Property Ltd | Construction | 2021 |
| Snowfox Holidays Limited | Administrative & support | 2003 |
| Solidum Group Limited | Other services | 2024 |
| Somerfield Barn Court Management Company Limited | Extraterritorial | 2001 |
| Somos Development Beheer Limited | Other services | 2024 |
| Somos Development Limited | Other services | 2024 |
| South East Properties and Maintenance Ltd | Real estate | 2021 |
| SOUTH28 Ltd. | Households | 2018 |
| Sparked Smart Ltd | Construction | 2026 |
| Specialist Coatings International Ltd | Administrative & support | 2015 |
| Specialistische Glazenwasserij Rinie Limited | Other services | 2020 |
| Spice Queen Ltd | Information & communication | 2011 |
| Spoedklussers Limited | Other services | 2023 |
| Spotlight Pest Control Services Limited | Agriculture & fishing | 2017 |
| Spring House Properties Limited | Real estate | 2015 |
| Springfield Management Company (Hythe) Limited | Real estate | 2013 |
| SRC Property Group Ltd | Real estate | 2026 |
| ST Leonards Court (Hythe) Ltd | Households | 2014 |
| ST. Margaret's Court Limited | Real estate | 1991 |
| Staalzorg Limited | Other services | 2025 |
| Stalvantis Ltd | Construction | 2025 |
| Star Taxi Services Limited | Transport & logistics | 2025 |
| Starkenborgh Nederland Limited | Other services | 2024 |
| Stella Chapman Ltd | Professional & scientific | 2010 |
| Steven PA Khian LAU Ltd | Health & social care | 2013 |
| Stevenhayes Limited | Real estate | 2026 |
| Stokes Bros. (Kent) Limited | Construction | 2003 |
| Stolberg Ltd | Arts & recreation | 2010 |
| Stone Farms Limited | Agriculture & fishing | 1965 |
| Strand Court RTM Company Limited | Households | 2011 |
| Streamugo Limited | Other services | 2024 |
| Streetspace Holdings Ltd | Financial services | 2020 |
| Streetspace Limited | Professional & scientific | 2016 |
| Stroja Beheer BV Limited | Other services | 2025 |