| Scottbaker Leisure Ltd | Administrative & support | 2025 |
| Screwed Barbers Ltd. | Other services | 2017 |
| SCS Structures Ltd | Construction | 2000 |
| SCS Training and Therapy Ltd | Health & social care | 2015 |
| SD Hart Engineering Services Limited | Construction | 2013 |
| SD Roofing & Construction Limited | Construction | 2023 |
| SDB Building Services Limited | Construction | 2006 |
| SDC Consultants International Ltd | Construction | 2023 |
| Sdmc Design Ltd | Information & communication | 2012 |
| SDPS17 Ltd | Health & social care | 2017 |
| SE Subsea Solutions Limited | Professional & scientific | 2023 |
| Seafort Global Technology Ltd | Information & communication | 2025 |
| Seafront Pizza (Seaton) Limited | Hospitality | 2025 |
| Seaman Scaffolding Ltd | Construction | 2026 |
| Sean Wiseman Property Services Limited | Construction | 2024 |
| Seasoned Professionals Recruitment Agency (Spra) Limited | Administrative & support | 2001 |
| Seasonedbusiness Ltd | Real estate | 2025 |
| Seateks Europe Limited | Professional & scientific | 2008 |
| Seattle Process Holdings Limited | Financial services | 2023 |
| Seattle Process Limited | Financial services | 2023 |
| Sebastian Knight Kitchens and Interiors Ltd | Wholesale & retail | 2021 |
| Sebcar Inspection Limited | Professional & scientific | 2023 |
| Secure UK IT Solutions Ltd | Information & communication | 2025 |
| Security Defence Group Ltd. | Administrative & support | 2019 |
| Sedgefield Dental Practice Limited | Health & social care | 2021 |
| Sedgefield Development Trust Limited | Other services | 2001 |
| Sedgefield Healthcare Limited | Health & social care | 2023 |
| Sedgefield Inspection Limited | Professional & scientific | 2019 |
| Sedgefield Pharmachem Ltd | Wholesale & retail | 2022 |
| Sedgefield Windows & Building Ltd | Construction | 2017 |
| Seecee Ltd | Wholesale & retail | 2026 |
| Seen Heard Believed Ltd | Health & social care | 2023 |
| SEG Digital Solutions Ltd | Wholesale & retail | 2025 |
| Select Data Solutions Ltd | Information & communication | 2017 |
| Select Financial Solutions North East LLP | | 2004 |
| Select+ Automotive Network Limited | Wholesale & retail | 2021 |
| Semester Student Planner Ltd | Education | 2021 |
| Semh Limited | Education | 2019 |
| Sencode Ltd | Information & communication | 2019 |
| Send & Literacy Support Ltd | Education | 2024 |
| Senior Authorised Services Ltd | Energy | 2021 |
| Sentinel Safety Consultancy Ltd | Professional & scientific | 2026 |
| Serenity Care and Home Ltd | Wholesale & retail | 2024 |
| Serenity Cars Ltd | Wholesale & retail | 2025 |
| Serenity Luxe Stays Limited | Hospitality | 2026 |
| Serviceline Occupational Health Limited | Health & social care | 2025 |
| SET Clothing Limited | Wholesale & retail | 2018 |
| Setanti Property and Investments Limited | Real estate | 2014 |
| Seven Seasons PVT Limited | Hospitality | 2025 |
| Sewells Car Accessories Limited | Wholesale & retail | 2008 |
| SF Guard Security Ltd | Administrative & support | 2024 |
| SF Training Solutions Ltd | Education | 2023 |
| SG Property Developments Limited | Construction | 2024 |
| SG Rentals Limited | Real estate | 2026 |
| SG Systems Solutions Ltd | Professional & scientific | 2017 |
| SGP Corpconsultancy Ltd | Professional & scientific | 2005 |
| SGP Corpmanagement Ltd | Professional & scientific | 2007 |
| SGZ Ltd | Wholesale & retail | 2021 |
| SH Digital Solutions Ltd | Information & communication | 2019 |
| SH Procurement Services Ltd | Wholesale & retail | 2025 |
| Shadow Limited | Professional & scientific | 2019 |
| Shafz Grill Ltd | Hospitality | 2025 |
| Shahyan Investments Ltd | Real estate | 2017 |
| Shanker Consultants Ltd | Health & social care | 2010 |
| Shared Waves CIC | Professional & scientific | 2026 |
| Sharedwords Ltd | Hospitality | 2025 |
| Sharif Pharm Ltd | Wholesale & retail | 2021 |
| Shark Corporation Ltd | Information & communication | 2024 |
| Sharp Razor (NE) Ltd | Other services | 2026 |
| Sharp Smiles Ltd | Health & social care | 2022 |
| Sharper Living Ltd | Households | 2026 |
| Shaun Enterprises Ltd | Financial services | 2025 |
| Shaun Hutchinson Ltd | Construction | 2025 |
| Shaw & Co Services Ltd | Real estate | 2021 |
| Shaw Investments Holdings Ltd | Extraterritorial | 2025 |
| Shaw Investments NE Ltd | Real estate | 2023 |
| Shaw Property Renovations Limited | Real estate | 2015 |
| Shaw Stays LLP | | 2023 |
| Sheard Services Ltd | Professional & scientific | 2026 |
| Shelbex Ltd | Wholesale & retail | 2021 |
| Shelmac Projects Ltd | Professional & scientific | 2017 |
| Shemul Dine Ltd | Hospitality | 2001 |
| Shepard Care and Support Services Ltd | Health & social care | 2022 |
| Shepherd M Limited | Wholesale & retail | 2022 |
| Sheraton Building Services Limited | | 1982 |
| Sheraton Choices Limited | Extraterritorial | 2013 |
| SHG Entertainment Limited | Education | 2015 |
| Shiakeex Limited | Hospitality | 2017 |
| Shimexex Limited | Hospitality | 2017 |
| Shine Four Limited | Other services | 2013 |
| Shine Three Limited | Other services | 2011 |
| Shinebright Development Limited | Health & social care | 2020 |
| Shiny Beauty Ltd | Other services | 2017 |
| Shiny Brow Bar Limited | Financial services | 2020 |
| Shinymind Limited | Information & communication | 2004 |
| Shkc Consult Ltd | Professional & scientific | 2023 |
| Shocktopus Limited | Information & communication | 2025 |
| Shoreline Fire Ltd | Administrative & support | 2021 |
| Shot Callers Ltd | Hospitality | 2025 |
| Shouri Homes Limited | Real estate | 2020 |