| Sumner Properties Limited | Real estate | 1963 |
| Sunday Division Limited | Wholesale & retail | 2026 |
| Sundeck Limited | Wholesale & retail | 1991 |
| Sunnyvacations Ltd | Hospitality | 2025 |
| Sunnyway Drive Limited | Households | 2022 |
| Sunset Round Limited | Information & communication | 2019 |
| Suntouched Productions Limited | Wholesale & retail | 1999 |
| Suntouched Sailboats Limited | Wholesale & retail | 2008 |
| Super Developments Limited | Real estate | 2016 |
| Super Living Property Limited | Real estate | 2020 |
| Super Signs Chichester Ltd | Manufacturing | 2023 |
| Superheat Refrigeration & Air Conditioning Ltd | Energy | 2026 |
| Supernormal Restaurants Limited | Hospitality | 2022 |
| Supernova Estates Limited | Real estate | 2020 |
| Supernova Psychotherapy, Training and Consultancy Services Ltd | Health & social care | 2021 |
| Superstar Homes Ltd | Households | 2022 |
| Superyacht Polishing Services Limited | Manufacturing | 2020 |
| Superyacht Resprays Limited | Extraterritorial | 2013 |
| Surcoat Ltd | Professional & scientific | 2025 |
| Sure Legal Solutions Limited | Administrative & support | 2016 |
| Surecalc Limited | Professional & scientific | 2007 |
| Surefields Farming Chichester Ltd | Agriculture & fishing | 2025 |
| Surefields Farming Limited | Agriculture & fishing | 2010 |
| Sureview Aerials Limited | Other services | 2003 |
| Surf Bay Pizza Ltd | Hospitality | 2015 |
| Surf Cerrito CIC | Education | 2023 |
| Surgical Precision Ltd | Health & social care | 2013 |
| Surrey Hydraulics Ltd | Manufacturing | 2021 |
| Surrey Publicans Limited | Hospitality | 2025 |
| Susan Payton Consultancy Ltd | Professional & scientific | 2015 |
| Suspended Ceiling Solutions Limited | Construction | 2013 |
| Sussex & Hampshire Denture Clinic Ltd | Health & social care | 2014 |
| Sussex Aggregates (Chichester) Ltd | Administrative & support | 2024 |
| Sussex Agri Power Limited | Agriculture & fishing | 1989 |
| Sussex and Surrey Brickwork Ltd Ltd | Construction | 2008 |
| Sussex Architectural Design Ltd | Professional & scientific | 2018 |
| Sussex Bar Company Limited | Hospitality | 2010 |
| Sussex Bookkeeping Services Limited | Professional & scientific | 2025 |
| Sussex Catering Equipment Co. Limited | | 1974 |
| Sussex Children's Therapy Service Ltd | Health & social care | 2011 |
| Sussex Construction (Chichester) Limited | Construction | 2010 |
| Sussex Consultancy Limited | Professional & scientific | 2017 |
| Sussex Creative Art Network CIC | Arts & recreation | 2024 |
| Sussex Design Build & Landscaping Ltd | Construction | 2024 |
| Sussex Diving Ltd | Arts & recreation | 2025 |
| Sussex Enterprise Marine Limited | Manufacturing | 2008 |
| Sussex Equine Dentistry Ltd | Professional & scientific | 2015 |
| Sussex Gardens Ltd | Administrative & support | 2019 |
| Sussex Grange Limited | Health & social care | 2003 |
| Sussex Heatcare Limited | Construction | 2002 |
| Sussex Heating Group Ltd | Construction | 2025 |
| Sussex Heritage Trust Limited | Professional & scientific | 1977 |
| Sussex Homesearch Limited | Real estate | 2003 |
| Sussex Hydraulics Ltd | Manufacturing | 2019 |
| Sussex IT Solutions Ltd | Information & communication | 2026 |
| Sussex Kitchen & Cabinet Company Ltd | Manufacturing | 2024 |
| Sussex Leisure Limited | Hospitality | 1998 |
| Sussex Plant & Machinery Hire Ltd | Administrative & support | 2022 |
| Sussex Plant Hire Ltd | Administrative & support | 2022 |
| Sussex Plant Ltd | Administrative & support | 2016 |
| Sussex Property Consultants Ltd | Other services | 2011 |
| Sussex Resin and Paving Ltd | Administrative & support | 2019 |
| Sussex Sandstone Limited | Mining & quarrying | 2003 |
| Sussex Scaffolding Group Ltd | Construction | 2021 |
| Sussex Scaffolding Ltd | Construction | 2021 |
| Sussex Static Caravans Limited | Wholesale & retail | 2025 |
| Sussex Storage Limited | Transport & logistics | 2014 |
| Sussex Surgical Specialists Ltd | Health & social care | 2017 |
| Sussex Transport Services Ltd | Transport & logistics | 2024 |
| Sussex Vehicle Body Repairs Svbr Ltd | Wholesale & retail | 2019 |
| Sussex View Surveys Limited | Professional & scientific | 2021 |
| Sussex Web Services Limited | Information & communication | 2007 |
| Sussex Wild Foods Limited | Manufacturing | 2016 |
| Sussex Window Repairs Limited | Construction | 2024 |
| Sussex-Cctv Ltd | Administrative & support | 2025 |
| Sustain Construction Limited | Construction | 2016 |
| Sutu Ltd | Real estate | 2021 |
| Swaffer Properties Limited | Real estate | 2021 |
| Swallow Bakery Partnerships 2 Ltd | Hospitality | 2019 |
| Swallow Bakery Partnerships Limited | Hospitality | 2015 |
| Swallow Events Ltd | Hospitality | 2017 |
| Swallows Management (Littlehampton) Limited | Households | 1973 |
| Swami Investments Ltd | Real estate | 2024 |
| Swaminathan (Sussex) Ltd | Real estate | 2020 |
| Swan Commercial Properties Limited | Real estate | 2007 |
| Swan Free House Limited | Hospitality | 2020 |
| Swan Garage (Worthing) Limited | Wholesale & retail | 1997 |
| Swan House Management (Haslemere) Limited | Real estate | 2014 |
| Swanfield Chapel | Other services | 2011 |
| Swanguard Limited | Professional & scientific | 1996 |
| Swanmore Roofing & Sons Ltd | Construction | 2025 |
| Swans Beauty Ltd | Other services | 2021 |
| Swaytech Services Ltd | Professional & scientific | 2017 |
| Sweat Ltd | Arts & recreation | 2019 |
| Sweet Dreamers Limited | Wholesale & retail | 2008 |
| Sweetman Holdings Limited | Financial services | 2025 |
| Sweets on Southgate Ltd | Wholesale & retail | 2025 |
| Swell Hair Limited | Manufacturing | 2012 |
| Swift Electrical Sussex Ltd | Construction | 2020 |
| Swift Group Sussex Ltd | Administrative & support | 2023 |