| Rosewarne Manor Limited | Real estate | 2025 |
| Route User Ltd | Information & communication | 2019 |
| ROX Installations Limited | Construction | 2018 |
| Saffron Cottage Furniture Ltd | Other services | 2013 |
| Saltings Reach Limited | Real estate | 2006 |
| Sandcastles Pre-School Playgroup | Education | 2003 |
| Sandy Toes Stays Ltd | Administrative & support | 2020 |
| Sapphire Holidays Limited | Information & communication | 2012 |
| Saryan Care Limited | Health & social care | 2021 |
| SBC Building Limited | Construction | 2025 |
| SBC Plumbing and Heating Ltd | Construction | 2024 |
| Scarlet Wines Limited | Wholesale & retail | 2009 |
| Sclcornwall Ltd | Professional & scientific | 2026 |
| Screenfix Ltd | Professional & scientific | 2025 |
| Sea Clearly Digital Ltd | Professional & scientific | 2021 |
| Sea Lane Management Company Limited | Households | 1987 |
| Seacore Ltd | Construction | 2020 |
| Seas Reach Carbis Bay Management Company Limited | Households | 2019 |
| Select IT Trading Limited | Information & communication | 2010 |
| Sensory Cove Ltd | Education | 2026 |
| Sequoia Property Services Limited | Extraterritorial | 2017 |
| Serene Construction Ltd | Construction | 2024 |
| SH2 Limited | Construction | 2016 |
| Shannon & Thomas Limited | Manufacturing | 2018 |
| Sharky's Fish & Chip Shop Limited | Hospitality | 2017 |
| Shredding World Ltd | Health & social care | 2024 |
| SJH Design Services Limited | Professional & scientific | 2003 |
| SK8PZ Love IT CIC | Arts & recreation | 2022 |
| Skylite Associates Limited | Professional & scientific | 2016 |
| Slimology Limited | Health & social care | 2003 |
| Small Shifts Community CIC | Education | 2025 |
| Small Shifts Limited | Other services | 2025 |
| Smart Marine Ltd | Manufacturing | 2023 |
| Smartimages Ltd | Professional & scientific | 2016 |
| Smith Cleaning Limited | Administrative & support | 2019 |
| South West Country Kitchens Ltd | Construction | 2021 |
| South West Trowels Limited | Construction | 2013 |
| Southern England Farms Limited | Agriculture & fishing | 1996 |
| Sovereign Consultancy (SW) Limited | Other services | 2021 |
| Spaceflight Index Ltd | Information & communication | 2022 |
| Spatchcock Brasseries Limited | Hospitality | 2013 |
| SPD Legal Ltd | Professional & scientific | 2024 |
| Spectrum Specialists Ltd | Health & social care | 2023 |
| Spruci Limited | Wholesale & retail | 2024 |
| ST Austell Festival of Children's Literature CIC | Education | 2025 |
| ST Erth Estates Limited | Construction | 2026 |
| ST IA Management Ltd | Real estate | 2014 |
| ST Ives Steeplejacks Ltd | Construction | 2014 |
| ST Ives Window Cleaners Ltd | Extraterritorial | 2019 |
| ST John's Court (Hayle) Management Company Limited | Households | 1990 |
| ST. Michael's Court (Penzance) Limited | Real estate | 2000 |
| Staysuite Ltd | Information & communication | 2026 |
| Steren Limited | Professional & scientific | 2011 |
| Stevens and Nicholls Limited | Construction | 2020 |
| Stevens Property Limited | Real estate | 2019 |
| Stevens Web Design Limited | Professional & scientific | 2014 |
| Streeva Ltd | Information & communication | 2015 |
| Studio Lowen Limited | Manufacturing | 2020 |
| Subsurface Data Management Consultants Limited | Professional & scientific | 2012 |
| Summit Roofing Solutions Limited | Construction | 2009 |
| Sunset Surfacing Ltd | Construction | 2024 |
| Swanson & Swanson Ltd | Hospitality | 2024 |
| Swathe Airborne Surveys Limited | Extraterritorial | 2011 |
| Swathe Sales and Support Limited | Professional & scientific | 2009 |
| Swathe Services (UK) Limited | Professional & scientific | 2004 |
| Swsws Ltd | Information & communication | 2024 |
| SZP Management Limited | Real estate | 2017 |
| T. J'S Carpets Limited | Wholesale & retail | 2004 |
| Taylor Made Digital Limited | Information & communication | 2016 |
| Technician Services Limited | Construction | 2024 |
| Terrill Bros. (Founders) Limited | Manufacturing | 1966 |
| THE Chynoweth Property Company Limited | Hospitality | 2004 |
| THE Cinnamon Trust | Health & social care | 2009 |
| THE Cornish Clothing Company Limited | Wholesale & retail | 2018 |
| THE Cornish GIN Distillery Limited | Professional & scientific | 2001 |
| THE Cornwall Independent School (UK) Ltd | Education | 2024 |
| THE Cottage Boutique Ltd | Hospitality | 2017 |
| THE Divorce Company South West Ltd | Other services | 2012 |
| THE Inclusion Hub C.I.C. | Information & communication | 2022 |
| THE Moon and Kingfisher (Hayle) Limited | Hospitality | 2012 |
| THE Olivetti Group Limited | Financial services | 2020 |
| THE Waite Room C.I.C. | Other services | 2021 |
| THE Watermill Cornwall Ltd | Hospitality | 2025 |
| THE Waters Edge -Beauty Therapy Ltd | Other services | 2023 |
| THE Wellbeing Surveyor Limited | Construction | 2023 |
| Thornton Solutions Ltd | Hospitality | 2025 |
| Three Mile Beach Holidays Ltd | Hospitality | 2020 |
| Three Mile Beach Limited | Real estate | 2015 |
| Thrive Wellness Cornwall Ltd | Health & social care | 2023 |
| Tigerx Limited | Professional & scientific | 2006 |
| Timber Mill Bespoke Carpentry & Joinery Ltd | Manufacturing | 2009 |
| TJ Lester Ltd | Financial services | 2014 |
| TML (SW) Holdings Limited | Real estate | 2020 |
| TML (SW) Limited | Construction | 2017 |
| Tolca Limited | Other services | 2017 |
| Toms Holidays (Holdings) Limited | Administrative & support | 2015 |
| TOO Much Collective Ltd | Wholesale & retail | 2023 |
| Towan Veterinary Services Ltd | Professional & scientific | 2025 |
| Towans Timberframe Ltd | Construction | 2014 |
| Traffic Made Easy Ltd | Information & communication | 2021 |