| Studio Whalefall Ltd | Information & communication | 2025 |
| Stutt Associates Limited | Professional & scientific | 2024 |
| Subconnected UK Ltd | Administrative & support | 2017 |
| Subram LLP | | 2022 |
| Suju Ltd | Information & communication | 2006 |
| Summergrand Limited | Real estate | 2003 |
| Sumtel Limited | Professional & scientific | 2008 |
| Sunflower Accounts Ltd | Professional & scientific | 2012 |
| Sunflower Formula Ltd | Professional & scientific | 2022 |
| Sunley Orford Retirement Homes | Hospitality | 1994 |
| Sunnyvale Developments Ltd. | Construction | 2020 |
| Sunnyvale Meadow Limited | Real estate | 2022 |
| Sunsave 2 Limited | Energy | 2011 |
| Super Clean Cornwall Ltd | Administrative & support | 2023 |
| Superior Render Supplies Limited | Wholesale & retail | 2016 |
| Suprema Medics Limited | Health & social care | 2020 |
| Surephase Consulting Ltd | Professional & scientific | 2015 |
| Surest Ltd | Administrative & support | 1997 |
| Surface Supply Ltd | Wholesale & retail | 2026 |
| Surfers Against Sewage | Other services | 1994 |
| Surfleet Services Limited | Professional & scientific | 2022 |
| Surgeon Siva Limited | Health & social care | 2019 |
| Surgilex Ltd | Health & social care | 2024 |
| Survival Wisdom Limited | Other services | 2009 |
| Sustainable Energy Investments Limited | Energy | 2021 |
| SW Commercials Limited | Wholesale & retail | 2009 |
| SW Furniture Supplies Limited | Wholesale & retail | 2023 |
| SW Solid Construction Limited | Construction | 2018 |
| SW11 Associates Ltd | Construction | 2023 |
| Swallowcourt Holdings Limited | Professional & scientific | 2008 |
| Swallowcourt Home Care Limited | Extraterritorial | 2010 |
| Swallowcourt Limited | Health & social care | 1983 |
| Swallowcourt Property (Keelex 176) Limited | Financial services | 2022 |
| Swallowcourt Property Company Limited | Financial services | 2022 |
| Swallowcourt Property Holdco Limited | Financial services | 2022 |
| Swallowcourt Trading Holdco Limited | Financial services | 2022 |
| Swan Developments (Truro) Limited | Real estate | 2012 |
| Swanpool Lettings Limited | Hospitality | 2025 |
| Swanpool Management Limited | Households | 1999 |
| Swanpool Project Ltd | Construction | 2019 |
| Swans Reach (Falmouth) Management Company Limited | Households | 2006 |
| Swartland Holdco Limited | Financial services | 2023 |
| Swif Smaller Loans Limited Partnership | | 2023 |
| Swig 7 Limited | Financial services | 2024 |
| Swig CIP Limited | Financial services | 2023 |
| Swig Finance Limited | Financial services | 1992 |
| Swig Newco Limited | Financial services | 2024 |
| Swig Swif Smaller Loans GP Limited | Financial services | 2023 |
| Swsolutions Ltd | Information & communication | 2025 |
| Sydyk Limited | Real estate | 2017 |
| Syllan Fish Ltd | Agriculture & fishing | 2025 |
| Synastry Ltd | Other services | 2026 |
| Synergy (SW) Limited | Administrative & support | 2008 |
| Synne Ellen Legal Limited | Professional & scientific | 2018 |
| Synsi Offshore Ltd | Construction | 2023 |
| Sysalt Ltd | Information & communication | 2017 |
| SYSTEM2SURGERY Ltd | Health & social care | 2022 |
| T & R Homes Ltd | Hospitality | 2025 |
| T B S (Nottingham) Limited | Administrative & support | 1991 |
| T C James & Sons Limited | Agriculture & fishing | 2012 |
| T W Round Limited | Construction | 2015 |
| Tacit Productions Limited | Arts & recreation | 2022 |
| Tagelin Limited | Information & communication | 2012 |
| Taharqa Ltd | Health & social care | 2022 |
| Taika Tales Ltd | Information & communication | 2018 |
| Talavera UK Limited | Manufacturing | 2024 |
| Talent Projects Ltd | Professional & scientific | 2026 |
| Talentshed Group Ltd | Administrative & support | 2019 |
| Talisman Enterprises Limited | Financial services | 2024 |
| Tall & Beautiful Clothing Ltd | Wholesale & retail | 2020 |
| Taluhi Investments Limited | Hospitality | 2026 |
| Tamar Hotel Supplies Limited | Administrative & support | 2019 |
| Tameem Enterprises Limited | Health & social care | 2022 |
| TAN & TAN Limited | Health & social care | 2019 |
| TAN Dowr Ltd | Wholesale & retail | 2023 |
| TAN Dowr Vodka Ltd | Wholesale & retail | 2023 |
| TAN Holdings Limited | Financial services | 2024 |
| Tarkus Simulation Ltd | Information & communication | 2026 |
| Tasman House Developments Limited | Real estate | 1997 |
| Taste and SEE Soul Food Kitchen Ltd | Hospitality | 2025 |
| Taterdu Properties Limited | Real estate | 1999 |
| Taupe Cakery Ltd | Hospitality | 2024 |
| Tax Acclaim Limited | Professional & scientific | 2014 |
| Taylor Cole Limited | Other services | 2021 |
| Taylormade Mortgages (South West) Ltd | Financial services | 2019 |
| Taylors of Grampound Limited | Health & social care | 2004 |
| Tbgenerations Limited | Information & communication | 2017 |
| TBH Barber Ltd | Other services | 2026 |
| TBH Limited | Professional & scientific | 2015 |
| TBL Ltd | Wholesale & retail | 2025 |
| TC Lang Bennetts Limited | Professional & scientific | 2024 |
| Tcdid Limited | Wholesale & retail | 2023 |
| TCS Retail Ltd | Other services | 2016 |
| TCS Truro Ltd | Wholesale & retail | 2024 |
| Teagle Machinery Limited | Manufacturing | 1996 |
| Teagle Property Ltd | Real estate | 2017 |
| Team Jess Limited | Professional & scientific | 2018 |
| TEC Girls Labs Ltd | Manufacturing | 2023 |
| Techmasters World Limited | Wholesale & retail | 2026 |
| Technical Electrical Engineering Limited | Construction | 1988 |