| Speak Truth to Power Ltd | Information & communication | 2016 |
| Spicer Aviation Ltd | Professional & scientific | 2011 |
| Srssm Ltd | Information & communication | 2026 |
| ST Aubyns (Hove) Limited | Hospitality | 2019 |
| ST Georges Road 72 RTM Company Limited | Households | 2025 |
| Stag 3D Design Ltd | Professional & scientific | 2026 |
| Stainless Steel Supplies Limited | Wholesale & retail | 1993 |
| Stanley's Post Limited | Professional & scientific | 2003 |
| Starkey Consultants Limited | Information & communication | 1999 |
| Starlight Structures Ltd | Construction | 2024 |
| Stars for Tomorrow UK Limited | Other services | 2024 |
| Stellar Point Limited | Professional & scientific | 2021 |
| Stema Professional Services Limited | Professional & scientific | 2002 |
| Steve Franklin and Sons Co Limited | Construction | 2008 |
| Stevemat Buildings & Groundworks Ltd | Construction | 2025 |
| Steyning and District Community Partnership Limited | Professional & scientific | 2007 |
| Steyning Antiques Limited | Wholesale & retail | 2018 |
| Steyning Atelier Ltd | Other services | 2025 |
| Steyning Community Hub Ltd | Arts & recreation | 2016 |
| Steyning Consulting Limited | Information & communication | 2018 |
| Steyning Downland Scheme Limited | Arts & recreation | 2009 |
| Steyning Holiday Cottages (Sussex) Ltd | Hospitality | 2024 |
| Steyning Interiors Ltd | Professional & scientific | 2023 |
| Steyning Roofing Limited | Construction | 2014 |
| Steyning Store Ltd | Wholesale & retail | 2022 |
| Steyning Systems Limited | Information & communication | 2005 |
| Stocker and Sons Limited | Construction | 1981 |
| Stogumber Securities Limited | Households | 1973 |
| Strength Shed Limited | Arts & recreation | 2019 |
| Stringer & Kitson Construction Ltd | Construction | 2016 |
| Striver Ambassadors Limited | Arts & recreation | 2025 |
| Structures Plus Ltd | Professional & scientific | 2024 |
| STS Risk Group Limited | Administrative & support | 1999 |
| Stuckton Workshop | Arts & recreation | 2025 |
| Sunwall Management Company Limited | Households | 1992 |
| Sure MEP Ltd | Construction | 2025 |
| Sussex Bodyworks Ltd | Wholesale & retail | 2025 |
| Sussex Building Contractors Ltd | Construction | 2023 |
| Sussex Cardiac Care Ltd | Health & social care | 2021 |
| Sussex Medical Group Limited | Health & social care | 2019 |
| Sussex Online Sales Limited | Wholesale & retail | 2026 |
| Sussex Vascular Services Limited | Health & social care | 2025 |
| Sussex Youth Theatre Limited | Arts & recreation | 2024 |
| Sussex-By-The-Sea Property Limited | Households | 2021 |
| Swift Wealth Management Ltd | Professional & scientific | 2021 |
| Symonds' Estates Ltd | Real estate | 2022 |
| Synchronicity Group Limited | Professional & scientific | 2004 |
| Synchronicity Services Limited | Professional & scientific | 2004 |
| Synchronicity Solutions Limited | Administrative & support | 2004 |
| Synchronicity Wealth Ltd | Administrative & support | 2018 |
| Syndown Residents Association Limited | Households | 2009 |
| Synergy Sunrise (Scarles Yard) Limited | Real estate | 2004 |
| Systemstyle Limited | Professional & scientific | 1982 |
| T Gosling Limited | Administrative & support | 2005 |
| T.S. Investments Limited | Construction | 1971 |
| TA Buxton Limited | Professional & scientific | 1998 |
| Table for One Ltd | Hospitality | 2025 |
| TAI CHI Wisdom Limited | Other services | 2006 |
| Tamp & Grind Ltd | Wholesale & retail | 2025 |
| Tanbridge Park Management Company Limited | Households | 1997 |
| Taste of India 2025 Limited | Hospitality | 2025 |
| TBC Operations Ltd | Administrative & support | 2026 |
| TC Accountants 004 Limited | Professional & scientific | 2018 |
| TC Accountants 007 Limited | Professional & scientific | 2021 |
| TC Accountants 017 Limited | Professional & scientific | 2022 |
| TC Accountants 020 Limited | Professional & scientific | 2023 |
| TC Accountants 021 Limited | Professional & scientific | 2023 |
| TC Accountants 026 Limited | Professional & scientific | 2024 |
| TC Accountants 029 Limited | Professional & scientific | 2025 |
| TC Accountants 030 Limited | Professional & scientific | 2025 |
| TC Accountants 031 Limited | Professional & scientific | 2025 |
| TC Accountants 033 Limited | Professional & scientific | 2025 |
| TC Accountants 033B Limited | Professional & scientific | 2025 |
| TC Accountants Limited | Professional & scientific | 2025 |
| TC Financial Planning Limited | Financial services | 2018 |
| TC Group Financial Planning LLP | | 2019 |
| TC Group Holdings Limited | Financial services | 2018 |
| TC NWC Limited | Professional & scientific | 2025 |
| TC Professional Services Limited | Professional & scientific | 2017 |
| TC Professional Trustees & Executors Ltd | Professional & scientific | 2018 |
| TC Sussex Limited | Professional & scientific | 2008 |
| TC Sussex SC Limited | Professional & scientific | 2025 |
| TDI Engineering Ltd | Manufacturing | 2015 |
| Telos Capital Limited | Information & communication | 2015 |
| Temple-Smithson Ltd | Information & communication | 2015 |
| TEQ4 Systems Limited | Wholesale & retail | 2015 |
| TEX Fleet Wash Limited | Other services | 2014 |
| Textilegarden Limited | Professional & scientific | 2009 |
| THE Alex Part Limited | Professional & scientific | 2002 |
| THE Baggage GUY Limited | Information & communication | 2025 |
| THE Beach (Cayman Islands) Ltd | Other services | 2015 |
| THE Bike Side Ltd | Arts & recreation | 2020 |
| THE Curious Herb Limited | Manufacturing | 2025 |
| THE Dermatology Doctor Limited | Health & social care | 2009 |
| THE Equity Studio LLP | | 2023 |
| THE Graphic Design Studio Ltd | Professional & scientific | 2023 |
| THE Hollies Residents Management Company Limited | Households | 2019 |
| THE Humorous History Company Limited | Wholesale & retail | 2025 |
| THE Jericho Trust | Hospitality | 2023 |
| THE Lion Rock Press UK Limited | Wholesale & retail | 2025 |