| SCT Therapies Ltd | Health & social care | 2026 |
| Sean Armstrong Fitness Ltd | Other services | 2018 |
| Seaview Fisheries NE Ltd | Wholesale & retail | 2025 |
| Seaweed & Co. Limited | Manufacturing | 2014 |
| Securiclad Holdings Limited | Financial services | 2022 |
| Securiclad Limited | Manufacturing | 2010 |
| Securiclad Properties Limited | Real estate | 2022 |
| Select NRG Limited | Administrative & support | 2017 |
| Select NRG North East Limited | Administrative & support | 2016 |
| Select Psychology Ltd | Health & social care | 2015 |
| Select Works Limited | Construction | 2021 |
| Self Line Ltd | Wholesale & retail | 2024 |
| Semper Paratus Solutions Ltd | Administrative & support | 2026 |
| Sentinel Safety Limited | Public administration | 2025 |
| Separation One Limited | Financial services | 2024 |
| Separation Two Limited | Financial services | 2024 |
| Serenity BJJ CIC | Arts & recreation | 2026 |
| Serenity Fitness Limited | Other services | 2020 |
| Serenity JIU Jitsu Limited | Other services | 2020 |
| SET Electrical Limited | Construction | 2020 |
| Seven Stars Free House Ltd | Hospitality | 2020 |
| Seventeen Twenty Three Limited | Wholesale & retail | 2026 |
| SF Legal Consultancy Ltd | Professional & scientific | 2021 |
| SGS Landscaping North East Limited | Construction | 2023 |
| Shabi's Kitchen Limited | Hospitality | 2025 |
| Shakti Engineering Limited | Professional & scientific | 2025 |
| Sharpe Recruitment Limited | Administrative & support | 2011 |
| Sharpness Point Limited | Hospitality | 2014 |
| Sharps Power Sport Ltd | Administrative & support | 2023 |
| Shining Stars Preschool Community Interest Company | Education | 2013 |
| Shirbon Ltd | Health & social care | 2020 |
| Shoestring Leisure Ltd | Hospitality | 2014 |
| Shore Creative Studio Ltd | Professional & scientific | 2025 |
| Shore Yoga Ltd | Health & social care | 2022 |
| Shoutclub Limited | Information & communication | 2018 |
| Shove Music Ltd | Information & communication | 2025 |
| Show Racism the Red Card | Education | 2006 |
| Shukoor Limited | Hospitality | 2018 |
| Shull Subsea Services Limited | Professional & scientific | 2020 |
| SHW Windows Limited | Construction | 2012 |
| Sifu and Co Ltd | Manufacturing | 2020 |
| Sigma Electrical Contracts (N.E) Limited | Construction | 2016 |
| Sigma Mechanical Contracts Limited | Construction | 2023 |
| Simon Smith Goalkeeping LLP | | 2023 |
| Simplified Operations Ltd | Administrative & support | 2023 |
| Simply Surveys Ltd | Professional & scientific | 2025 |
| Simpson Regeneration Services Limited | Construction | 2019 |
| Sinox Star FX Limited | Information & communication | 2022 |
| SIX Nine Design Studio Limited | Construction | 2010 |
| SJ Catering Consultancy Ltd | Professional & scientific | 2026 |
| SJ Flat Roofing Ltd | Construction | 2022 |
| SJ Plumbing and Heating NE Limited | Construction | 2025 |
| SJB Trucks Ltd | Wholesale & retail | 2015 |
| SJC Leisure Limited | Extraterritorial | 2018 |
| SJM Access and Inspection Ltd | Construction | 2017 |
| SKI Promotions Limited | Other services | 2004 |
| SKN IQ Skin Clinic Ltd | Other services | 2023 |
| Skullduggeri Hair & Beauty Ltd | Extraterritorial | 2016 |
| Skullduggeri Limited | Other services | 2007 |
| Skytube Solutions Ltd | Construction | 2026 |
| Slae Hair Ltd | Other services | 2025 |
| Slay Studios NE Ltd | Other services | 2025 |
| Sleep Well NE Ltd | Hospitality | 2025 |
| Slendershots International Limited | Wholesale & retail | 2019 |
| Slice One Bristol Ltd | Hospitality | 2026 |
| Slice One Collective Ltd | Financial services | 2026 |
| SM Installations Ltd | Construction | 2025 |
| SM the Pioneer Ltd | Hospitality | 2024 |
| Smallburn Properties Ltd | Real estate | 2014 |
| Smart Mart North East Ltd | Wholesale & retail | 2026 |
| Smile Wide Ltd | Manufacturing | 2021 |
| Smith Consultancy Ltd | Information & communication | 2025 |
| Smiths Dock 1922 Ltd | Other services | 2026 |
| Smithson Wealth Management Limited | Professional & scientific | 2018 |
| SMM15 Ltd | Arts & recreation | 2022 |
| SNA Shopfitting Limited | Construction | 2020 |
| Sneo Ltd | Wholesale & retail | 2022 |
| Snow Films Ltd | Information & communication | 2016 |
| Solvetech Support Ltd | Other services | 2022 |
| Somos Italianos Ltd | Professional & scientific | 2020 |
| Sonder Pictures Ltd | Information & communication | 2024 |
| Soul Mates Pet Funeral Services Ltd | Other services | 2026 |
| Soul to Soil Ltd | Manufacturing | 2026 |
| Southern Electronics (UK) Ltd | Manufacturing | 2012 |
| Southshieldsspice Limited | Hospitality | 2024 |
| Space Builders North East Limited | Construction | 2025 |
| Spaceprime Property Management Limited | Households | 1989 |
| Sparkling Beautique Ltd | Other services | 2022 |
| Spartan Healthcare Ltd | Health & social care | 2019 |
| Spearpoint Business Solutions Ltd | Administrative & support | 2024 |
| Spectrum Audio Visual Limited | Arts & recreation | 2025 |
| Spectrum Fireworks and Special Effects Limited | Administrative & support | 2017 |
| Speedy Parcel Solutions Limited | Transport & logistics | 2022 |
| Sphere Byte Solutions Ltd | Information & communication | 2018 |
| Spiffing Prints Ltd | Manufacturing | 2017 |
| Spina Colada Ltd | Information & communication | 2021 |
| SPINER247 Consulting Limited | Professional & scientific | 2024 |
| Spirit Hair Design Ltd | Other services | 2008 |
| Spirited People and Change Consultancy Ltd | Professional & scientific | 2024 |
| Spran Pitsea Commercial Limited | Real estate | 2024 |