| Study Dealer Limited | Education | 2025 |
| Study Holidays Limited | Professional & scientific | 1998 |
| Studysesh Ltd | Information & communication | 2025 |
| Studyspace Global Limited | Information & communication | 2023 |
| Studyspace World Limited | Wholesale & retail | 2022 |
| Stuntone Trading Co., Limited | Wholesale & retail | 2022 |
| Sturdy Services Limited | Other services | 1999 |
| Sturges Parkway Ltd | Professional & scientific | 2024 |
| Style Home and Gardens Limited | Construction | 2014 |
| SU & RU Ltd | Hospitality | 2021 |
| Sub-Nautical Legion Robotics Limited | Professional & scientific | 2026 |
| Subcablenews Ltd | Information & communication | 2010 |
| Sublime Marketing Design Limited | Administrative & support | 2011 |
| Subscale Limited | Information & communication | 2022 |
| Substrate Biochar Ltd | Water & waste | 2024 |
| Substrate Limited | Financial services | 2026 |
| Success Solutions Global Ltd | Administrative & support | 2019 |
| Suchowski Holdings Limited | Financial services | 2015 |
| SUCOP3 Ltd | Real estate | 2024 |
| SUD Italy Ltd | Hospitality | 2023 |
| Sudx Ltd | Wholesale & retail | 2025 |
| Suffolk Country Properties Limited | Wholesale & retail | 2006 |
| Suffolk Dog Grooming Academy Limited | Professional & scientific | 2016 |
| Suffolk Independent Midwives Limited | Health & social care | 2005 |
| Sugon International Cross-Border Media Co., Ltd | Wholesale & retail | 2025 |
| Suhao Global Ltd | Wholesale & retail | 2020 |
| Suihe Marine Engineering Co., Ltd | Wholesale & retail | 2024 |
| Sujendran Limited | Health & social care | 2013 |
| Sujia Import ADN Export Co., Limited | Manufacturing | 2024 |
| Sulgrave Advisors Limited | Administrative & support | 2018 |
| Sullinvest Ltd | Real estate | 2024 |
| Sulston's Kitchen Limited | Hospitality | 2016 |
| Sultan International Trading Company Limited | Wholesale & retail | 2024 |
| Sulven Tech Ltd | Manufacturing | 2026 |
| Sumach UK Limited | Professional & scientific | 2007 |
| Sumarokov Ltd | Manufacturing | 2024 |
| Summers Aviation Ltd | Transport & logistics | 2022 |
| Summit Biotechnology Ltd | Professional & scientific | 2011 |
| Summit Defence Ltd | Manufacturing | 2018 |
| Summit Kitchen Ltd | Wholesale & retail | 2020 |
| Summit Oxygen International Limited | Manufacturing | 2005 |
| Summit Oxygen Ltd | Manufacturing | 2018 |
| Summit Risk Consulting Ltd | Professional & scientific | 2021 |
| Summit Technology Consulting Limited | Professional & scientific | 2010 |
| Sumner & Skye Ltd | Wholesale & retail | 2026 |
| Sumplexity Ltd | Information & communication | 2025 |
| Sun and Nails Ltd | Other services | 2025 |
| Sun Paper UK Ltd | Extraterritorial | 2022 |
| Sunbeam Park Limited | Hospitality | 2025 |
| Sunbreak (UK) Green Care Technology Limited | Extraterritorial | 2015 |
| Suncoma Limited | Health & social care | 2022 |
| Sundrany Car Sales Limited | Extraterritorial | 2024 |
| Sunflowers Care Limited | Health & social care | 2012 |
| Sunfury Trading (UK) Ltd | Wholesale & retail | 2025 |
| Sungue Ltd | Professional & scientific | 2021 |
| Sunley International Co., Ltd | Wholesale & retail | 2023 |
| Sunmed Ltd | Manufacturing | 2026 |
| Sunne Technology Limited | Manufacturing | 2024 |
| Sunningdale Life Ltd | Real estate | 2021 |
| Sunny (Asia) Industry Co., Ltd | Extraterritorial | 2017 |
| Sunny Golden Words Limited | Information & communication | 2025 |
| Sunny Look Limited | Hospitality | 2002 |
| Sunny Machinery Co., Ltd | Extraterritorial | 2016 |
| Sunnyacres Management Company Limited | Households | 1990 |
| Sunnyside Property Management Company Limited | Real estate | 2007 |
| Suno Innova Ltd | Health & social care | 2018 |
| Sunrise Business Park Limited | Financial services | 2011 |
| Sunrise Group Industry Co., Ltd | Extraterritorial | 2017 |
| Sunrise Industry Co., Ltd. | Extraterritorial | 2020 |
| Sunrise Service Limited | Administrative & support | 2026 |
| Sunrise Silicone Hose Co., Limited | Manufacturing | 2025 |
| Sunrise Systems Limited | Information & communication | 1985 |
| Sunscen Group (UK) Co., Ltd | Extraterritorial | 2015 |
| Sunshine SYS Industry Limited | Manufacturing | 2019 |
| SUNSHINE-5 LLP | | 2022 |
| Sunwen Industry Co., Ltd | Wholesale & retail | 2023 |
| Super Instrument Ltd | Extraterritorial | 2015 |
| Super Kebab House Limited | Hospitality | 2024 |
| Super-Sharp Space Systems Limited | Professional & scientific | 2017 |
| SUPER7ONE Ltd | Wholesale & retail | 2018 |
| Superalignment Ltd | Information & communication | 2026 |
| Superbio.Ai Ltd | Information & communication | 2022 |
| Superbrnds Limited | Information & communication | 2014 |
| Superflat Games Ltd | Information & communication | 2012 |
| Superherbs International Ltd | Health & social care | 2015 |
| Superintelligence Ltd | Information & communication | 2020 |
| Superior Solutions Group Ltd | Administrative & support | 2026 |
| Superminds Tutoring Ltd | Education | 2025 |
| Supernature Garden LLP | | 2018 |
| Superstar Gift and Toys Co., Ltd | Wholesale & retail | 2022 |
| Supervim Home UK Ltd | Wholesale & retail | 2023 |
| Supplenta Limited | Information & communication | 2002 |
| Suppli Ltd | Information & communication | 2013 |
| Supply Grid Ltd | Extraterritorial | 2026 |
| Supply Plus Limited | Manufacturing | 1972 |
| Support Air World Ltd | Manufacturing | 2025 |
| Support Robotics Limited | Information & communication | 2017 |
| Sureflap Limited | Manufacturing | 2007 |
| Surginnofy Ltd | Professional & scientific | 2021 |
| Surprise Composites Ltd | Manufacturing | 2019 |