| Skhb Property Limited | Real estate | 2022 |
| Skin & Soul Academy Ltd | Other services | 2024 |
| Skin Fade Barber Ltd | Other services | 2022 |
| Skin Rehab Clinic Ltd | Health & social care | 2020 |
| Skin Self-Care Ltd | Other services | 2025 |
| Skkido Technology Ltd | Information & communication | 2025 |
| SKS Construction (NE) Limited | Construction | 2025 |
| Skyflo Digital Ltd | Information & communication | 2022 |
| Skyknight Ltd | Information & communication | 2016 |
| Skyline Electrical Services Ltd | Manufacturing | 2022 |
| Skyline Problast Services Ltd | Manufacturing | 2025 |
| SL Lambert Ltd | Health & social care | 2023 |
| Sl&G Properties Limited | Real estate | 2024 |
| SLA Ductwork Ltd | Construction | 2021 |
| Slabs Direct UK Limited | Wholesale & retail | 2023 |
| Slaley Retreat Limited | Hospitality | 2025 |
| Slate Scaffolding Ltd | Construction | 2026 |
| Slaters Motor Group Ltd | Wholesale & retail | 2021 |
| Slayco Limited | Construction | 2005 |
| SLC Properties NE Ltd | Real estate | 2026 |
| Sleep Success Ltd | Health & social care | 2022 |
| Slimmetry Ltd | Health & social care | 2025 |
| Slimzy Stitches Limited | Manufacturing | 2026 |
| SLM Roofing Limited | Construction | 2015 |
| SLOG2 Software Limited | Information & communication | 2025 |
| Sloogs Services Ltd | Transport & logistics | 2020 |
| Sltl Designs Ltd | Wholesale & retail | 2025 |
| SLW (Holdings) Limited | Hospitality | 2014 |
| SLW (Thornbury) Limited | Health & social care | 2016 |
| SLW Limited | Health & social care | 1995 |
| Slwindows Ltd | Construction | 2026 |
| SM1 Group Ltd | Information & communication | 2021 |
| Small Business Bookkeeping Limited | Professional & scientific | 2021 |
| Small Feet Energy Limited | Construction | 2011 |
| Smart Approaches Limited | Information & communication | 2023 |
| Smart Consultancy NE Ltd | Real estate | 2025 |
| Smart Development NE Ltd | Construction | 2025 |
| Smart Flow - NE Limited | Water & waste | 2021 |
| Smart Media Group Ltd | Financial services | 2021 |
| Smart Origin Ltd | Professional & scientific | 2021 |
| Smart Payment Solutions Ltd | Wholesale & retail | 2025 |
| Smart Recruit Group Limited | Administrative & support | 2022 |
| Smart Tax & Accountancy Services Ltd | Professional & scientific | 2018 |
| Smart Tote Ltd | Administrative & support | 2023 |
| Smart Vision & Communications Ltd | Professional & scientific | 2021 |
| Smartcoat Access Ltd | Construction | 2026 |
| Smartyzbeautylounge Ltd | Wholesale & retail | 2025 |
| Smash Padel North East Ltd | Arts & recreation | 2025 |
| Smith and Churchill Limited | Real estate | 2013 |
| Smith Construction NE Ltd | Construction | 2025 |
| Smugglers Coffee Co Ltd | Wholesale & retail | 2022 |
| SN Legal Limited | Professional & scientific | 2018 |
| Snagging Expert Services Ltd | Construction | 2025 |
| Snop UK Limited | Manufacturing | 2009 |
| Snow Goose Limited | Hospitality | 1994 |
| Snowleopard Media Limited | Wholesale & retail | 2025 |
| Snowwane Limited | Information & communication | 2021 |
| SNW Home Improvements Ltd | Construction | 2025 |
| SO Smooth Co Ltd | Wholesale & retail | 2021 |
| SO WOK Noodle Bar Takeaway Ltd | Hospitality | 2024 |
| Social by Oceander CIC | Health & social care | 2024 |
| Social Chef Ltd | Hospitality | 2012 |
| Social Housing Partnership Limited | Real estate | 2021 |
| Sockbridge Limited | Real estate | 2021 |
| Sofa Centre Ltd | Wholesale & retail | 2024 |
| Software Dark Factory Ltd | Information & communication | 2026 |
| SOL Saman Ltd | Information & communication | 2025 |
| Solar Spares Limited | Other services | 2026 |
| Solariswisp Technologies Limited | Professional & scientific | 2024 |
| Solas Physiotherapy Ltd | Health & social care | 2025 |
| Solis NE Ltd | Other services | 2026 |
| Solo Pizza (North East) Ltd | Hospitality | 2025 |
| Solo Pizza (Tyne & Wear) Ltd | Hospitality | 2015 |
| Solo SP Retail Limited | Wholesale & retail | 2021 |
| Something Different Interiors Limited | Wholesale & retail | 2018 |
| Something Else Music Limited | Arts & recreation | 2005 |
| Sonishspace Limited | Health & social care | 2025 |
| Sonnet 43 Brewery Ltd | Manufacturing | 2016 |
| Sophus Consulting Limited | Professional & scientific | 2013 |
| Sopranos Durham Ltd | Hospitality | 2015 |
| Sorotzkin Properties Ltd | Real estate | 2017 |
| Sorrento North East Ltd | Hospitality | 2017 |
| Sosi Electrical Ltd | Construction | 2022 |
| Soul Bride Ltd | Wholesale & retail | 2025 |
| Source Point Distribution Ltd | Wholesale & retail | 2025 |
| Sourena Pizza Ltd | Hospitality | 2025 |
| South Hylton and Pennywell Enterprise CIC | Water & waste | 2024 |
| South Hylton Properties Ltd | Real estate | 2009 |
| South Tyne Healthcare Limited | Wholesale & retail | 2018 |
| South Tyneside Orthodontic Centre Ltd | Health & social care | 2018 |
| Southwick Carpet & Bedding Centre Limited | Wholesale & retail | 2014 |
| Southwick Consultants Ltd | Other services | 2023 |
| Southwick House Limited | Hospitality | 2024 |
| Space North East CIC | Other services | 2022 |
| Spacebar Arcade Ltd | Hospitality | 2024 |
| Sparkling Touch Cleaning Limited | Administrative & support | 2025 |
| Sparks and Water Limited | Professional & scientific | 2025 |
| Sparks NE Ltd | Manufacturing | 2018 |
| Spartan Martial Arts Academy CIC | Education | 2024 |
| Speakeasy North East Ltd | Hospitality | 2022 |