| Superink Limited | Administrative & support | 2005 |
| Supermediation Limited | Information & communication | 2011 |
| Supernova VPN Ltd | Information & communication | 2025 |
| Supplement Supplies Direct Ltd | Wholesale & retail | 2025 |
| Supply.Com Limited | Wholesale & retail | 2000 |
| Support Services (Newcastle) Limited | Administrative & support | 2003 |
| Supreme Crust Pizza Ltd | Hospitality | 2019 |
| Supreme Exterior Clean Ltd | Construction | 2018 |
| Supreme Health Care Limited | Health & social care | 1992 |
| Sure Eats Ltd | Wholesale & retail | 2026 |
| Surecare Newcastle Limited | Health & social care | 2017 |
| Sureclad North East Ltd | Construction | 2011 |
| Suretree Limited | Agriculture & fishing | 2017 |
| Surf Financial Services Limited | Financial services | 2020 |
| Surff Limited | Information & communication | 2024 |
| Surfman Property Investment Limited | Real estate | 2021 |
| Surfman-Uk Limited | Information & communication | 2018 |
| Surgery Plus Ltd | Health & social care | 2022 |
| Surgical Technologies Ltd | Information & communication | 2020 |
| Surma Tandoori North East Limited | Hospitality | 2023 |
| SURPASS13 Limited | Construction | 2026 |
| Sursum Corda Limited | Real estate | 2000 |
| Surtees Engineers Limited | Manufacturing | 1965 |
| Survey & Marketing Services Limited | Professional & scientific | 1989 |
| Survey North Ltd | Professional & scientific | 2023 |
| Survotech Limited | Information & communication | 2026 |
| Surya Itops Consultants Limited | Information & communication | 2019 |
| Susan's Snacks Ltd | Hospitality | 2015 |
| Sushi ME Rollin’ Ltd | Hospitality | 2018 |
| Sussed and Able Ltd | Professional & scientific | 2021 |
| Sustainability Energy Innovation Ltd | Manufacturing | 2022 |
| Sustainable Business Solutions Ltd | Professional & scientific | 2021 |
| Sustainable Climate Solutions Limited | Construction | 2024 |
| Sustainable Financial Solutions Limited | Professional & scientific | 2026 |
| Sustainaswitch Ltd | Professional & scientific | 2025 |
| Sutherland Legal Solutions Limited | Professional & scientific | 2017 |
| Sutton Services International Limited | Construction | 1991 |
| Sutton Wakefield Ltd | Wholesale & retail | 2025 |
| Suzanne Graham Estate Agents (LOW Fell) Limited | Real estate | 2005 |
| Suzanne Graham Estate Agents (Prudhoe) Limited | Real estate | 2007 |
| Suzanne Graham Estate Agents (Whickham) Limited | Real estate | 2005 |
| Suzen Services Ltd | Administrative & support | 2019 |
| Suzhou Stealth Energy Technology UK Ltd | Wholesale & retail | 2022 |
| Suzie Winsor Limited | Arts & recreation | 2015 |
| Suzy Hails Ltd | Professional & scientific | 2017 |
| SVB Consultancy & Solutions Limited | Professional & scientific | 2012 |
| Sviatoslav Tarasenko Biophotonics and Systemic Aqua Engineering Ltd | Manufacturing | 2022 |
| SVL Trade Limited | Wholesale & retail | 2024 |
| Svlj Ltd | Professional & scientific | 2025 |
| SVN Quantity Surveying Limited | Professional & scientific | 2021 |
| SVP Health Care Limited | Health & social care | 1988 |
| SW Global Ltd. | Information & communication | 2015 |
| SW Installations Limited | Construction | 2014 |
| SW North Limited | Professional & scientific | 2023 |
| SW Property Lettings Ltd | Real estate | 2026 |
| SW4 Services Limited | Other services | 2017 |
| Swales Health Ltd | Other services | 2014 |
| Swallowflight Limited | Professional & scientific | 1990 |
| Swalwell Cafe Ltd | Hospitality | 2025 |
| Swalwell Car & Storage Ltd | Wholesale & retail | 2025 |
| Swan & Thorpe Developments Limited | Real estate | 2024 |
| Swan Residential Lettings Ltd | Real estate | 2017 |
| Swanbrook Transport Limited | Transport & logistics | 2002 |
| Swann Property Investments Ltd | Real estate | 2021 |
| Swans Pharma Ltd | Professional & scientific | 2022 |
| Swanson Holdings Limited | Health & social care | 2022 |
| Swantech Engineering Consulting Limited | Information & communication | 2026 |
| Swapnam Ltd | Education | 2021 |
| Swatrix Ltd | Wholesale & retail | 2025 |
| Swav Beauty Ltd | Other services | 2022 |
| Swav Entertainment Group Ltd | Professional & scientific | 2021 |
| Swav Hair Ltd | Other services | 2019 |
| Sweeney Energy Services Ltd | Professional & scientific | 2025 |
| Sweet Betty BON Bons Ltd | Manufacturing | 2014 |
| Sweet Dreams Dessert Cafe Ltd. | Hospitality | 2015 |
| Sweet Garden Stanley Limited | Hospitality | 2021 |
| Sweet Home NE Ltd | Hospitality | 2025 |
| Sweet Ice Ltd | Hospitality | 2024 |
| Sweet Passion Ltd | Wholesale & retail | 2024 |
| Sweet Ting (HLP) Limited | Hospitality | 2022 |
| Sweetest Homes Ltd | Real estate | 2021 |
| Sweetline Desserts Limited | Hospitality | 2024 |
| Swel Weldfab Limited | Manufacturing | 2020 |
| Swfc Women’S Supporters Group CIC | Arts & recreation | 2023 |
| Swift Applications Limited | Information & communication | 2012 |
| Swift Architecture Ltd | Professional & scientific | 2023 |
| Swift Auto Travel Ltd | Transport & logistics | 2000 |
| Swift Hire Solutions Ltd | Transport & logistics | 2012 |
| Swift NE Limited | Transport & logistics | 2024 |
| Swift Plumbing and Drains Limited | Construction | 2026 |
| Swift Veritas Yield Ltd | Construction | 2021 |
| Swiftgo Logistics UK Limited | Wholesale & retail | 2025 |
| SWIFTSTORE101 Ltd | Wholesale & retail | 2024 |
| Swim NE Limited | Arts & recreation | 2008 |
| Swimming Club Data Systems Ltd | Information & communication | 2021 |
| Swimtime Limited | Arts & recreation | 1989 |
| Swingbridge Finance Limited | Financial services | 2018 |
| Swiss Dissh Limited | Hospitality | 2023 |
| Swiss Land Group Limited | Professional & scientific | 2014 |
| Swiss Medicare Limited | Wholesale & retail | 2014 |