| Sunshine 68 Limited | Hospitality | 2019 |
| Sunshine Builders NE Ltd | Construction | 2024 |
| Super NOVA90 Ltd | Administrative & support | 2021 |
| Supercare Solutions Ltd | Health & social care | 2019 |
| Superior Renovation Services Ltd | Construction | 2018 |
| Superlec Direct Limited | Extraterritorial | 2013 |
| Superlec Electrical Distributors Limited | Wholesale & retail | 1981 |
| Supernova Industries Ltd | Wholesale & retail | 2024 |
| Supernova Technical Solutions Limited | Professional & scientific | 2025 |
| Superprimeresi.Com Ltd | Information & communication | 2015 |
| Superstile Ltd. | Professional & scientific | 2014 |
| Supplanter Properties Ltd | Real estate | 2021 |
| Supporting Hands NE Limited | Health & social care | 2022 |
| Supporting Independence Outreach Services Ltd | Health & social care | 2016 |
| Supreme Clean 24/7 Limited | Other services | 2016 |
| Supreme Garage Doors Limited | Manufacturing | 2017 |
| Supreme Landscapes (Great Ayton) Limited | Administrative & support | 2019 |
| Supreme Minibus Hire Ltd | Transport & logistics | 2020 |
| Supreme Properties (NE) Limited | Real estate | 2024 |
| Supreme Sandstone Limited | Manufacturing | 2017 |
| Supremesales Ltd | Wholesale & retail | 2022 |
| Supremo’S Redcar Ltd | Hospitality | 2026 |
| SURETAN25 Ltd | Other services | 2025 |
| Surge Marketing Solutions Ltd | Information & communication | 2014 |
| Survx Limited | Administrative & support | 2019 |
| Sushi Panda Ltd | Hospitality | 2023 |
| Sustainable Development Network Limited | Other services | 2002 |
| Sutcliffe Wallace Limited | Agriculture & fishing | 2002 |
| Sutton Lodge Investco Limited | Energy | 2022 |
| Suzy Kitching Consultancy Limited | Health & social care | 2026 |
| SV Valeting Centre Ltd | Other services | 2025 |
| Svitzer Eastlands Pension Trustees Limited | Extraterritorial | 2019 |
| Svitzer Marine Limited | Transport & logistics | 1901 |
| Svitzer Terminals Limited | Transport & logistics | 2023 |
| Svitzer UK Trustees Limited | Extraterritorial | 2011 |
| Svji Limited | Real estate | 2025 |
| Svjn Services Limited | Construction | 2016 |
| Svsoftech Ltd | Information & communication | 2025 |
| SW Investment & Procurement Ltd | Real estate | 2021 |
| SW7 Financial Ltd | Financial services | 2025 |
| Swagbroindustries Ltd | Hospitality | 2025 |
| Swagger & Slick Limited | Other services | 2016 |
| Swahili Taste Box Ltd | Hospitality | 2018 |
| Swainby L&R Limited | Construction | 2023 |
| Swaledale Structures Limited | | 1976 |
| Swallow Associates (Stokesley) Limited | Professional & scientific | 2010 |
| Swangate Ltd | Wholesale & retail | 2011 |
| Swann Developments Limited | Real estate | 1993 |
| Swavy Limited | Wholesale & retail | 2020 |
| SWD (NE) Ltd | Construction | 2022 |
| Sweet Escape Deserts Ltd | Wholesale & retail | 2024 |
| Sweet Shack MB Ltd | Hospitality | 2025 |
| Swerve Table Tennis Club CIC | Education | 2025 |
| Swift Capital Group Limited | Financial services | 2024 |
| Swift Collective Co. Ltd | Wholesale & retail | 2025 |
| Swift Inspection Services Ltd | Professional & scientific | 2023 |
| Swift Mobiles and Vapes Ltd | Wholesale & retail | 2023 |
| Swift Plumbing Solutions Limited | Construction | 2026 |
| Swiftfix Properties Limited | Construction | 2024 |
| Swim With DAN Ltd | Education | 2022 |
| Swinn Engineering Limited | Professional & scientific | 2007 |
| Swish Home Improvements Limited | Construction | 2017 |
| SWO Renewables Ltd | Construction | 2025 |
| SWP International Limited | Wholesale & retail | 2022 |
| Swpaid Limited | Professional & scientific | 2025 |
| SYB Transport Ltd | Transport & logistics | 2026 |
| Syed Anas Bukhari Ltd | Wholesale & retail | 2025 |
| Syedsanaurrehmanbukhari Ltd | Wholesale & retail | 2026 |
| Sylhet's Spice Limited | Hospitality | 2015 |
| Sylvan Lore Limited | Education | 2021 |
| SYM15 Ltd | Administrative & support | 2017 |
| Symbol Signs & Screenprint Limited | Administrative & support | 2002 |
| Syndicate Engineering Ltd | Professional & scientific | 2023 |
| Synergy Pro Network Ltd | Professional & scientific | 2025 |
| Synergy Teesside Ltd. | Health & social care | 2014 |
| Syntex Engineering Services Limited | Construction | 1983 |
| T & E Joiners Limited | Manufacturing | 2012 |
| T & H M Ltd | Administrative & support | 2015 |
| T & P Developments Ltd | Households | 2023 |
| T & T Coatings Limited | Construction | 2003 |
| T a N Aero Consulting Ltd | Professional & scientific | 2026 |
| T Foster Engineering Limited | Construction | 2009 |
| T Francis Electrical Ltd | Construction | 2016 |
| T H B Trade Ltd | Wholesale & retail | 2025 |
| T H E Land Co Ltd | Real estate | 2024 |
| T N Kelly & Company Limited | Transport & logistics | 2006 |
| T Rookes Scaffolding Ltd | Construction | 2022 |
| T S Fabrications Limited | Manufacturing | 2012 |
| T&A Real Estate Ltd | Real estate | 2022 |
| T&B Neill Limited | Professional & scientific | 2024 |
| T&P Solutions Ltd | Manufacturing | 2021 |
| T&S Toasy Kitchen Ltd | Hospitality | 2026 |
| T&T Energy Limited | Energy | 2024 |
| T-Mec Engineering Ltd | Administrative & support | 2010 |
| T.A.L.K. Safety Ltd | Professional & scientific | 2011 |
| T.B.Blades. Ltd | Manufacturing | 2026 |
| T.B.C.C.K Ltd | Construction | 2025 |
| T.E Property Ltd | Professional & scientific | 2023 |
| T.W. Walker Limited | Wholesale & retail | 1962 |
| T7TRADER Ltd | Construction | 2019 |