| Runaway Training Ltd | Administrative & support | 2022 |
| Rural Property Developments Limited | Extraterritorial | 2016 |
| Russau Consulting Ltd | Information & communication | 2024 |
| Rustic Roots Bistro Ltd | Wholesale & retail | 2024 |
| RV3 Limited | Construction | 2022 |
| Ryan Gill Electrical Limited | Construction | 2025 |
| S & D Commercial Solutions Limited | Construction | 2026 |
| S & D Services (North) Limited | Construction | 2026 |
| S & S 20 Property Limited | Real estate | 2020 |
| S & S Lydon Holdings Limited | Financial services | 2026 |
| S O'Brien + Sons Plumbing and Heating Ltd | Construction | 2017 |
| S Thompson Groundwork’S Ltd | Construction | 2025 |
| S&C Play Cafe Ltd | Wholesale & retail | 2026 |
| S&V Healthcare Ltd | Health & social care | 2023 |
| S. Lightfoot Roofing Ltd | Construction | 2022 |
| S. Wilson Roofing Ltd | Construction | 2023 |
| S.A.Stoys Limited | Wholesale & retail | 2024 |
| S.F GAS Ltd | Other services | 2017 |
| Sacriston Auto Dismantlers Ltd | Water & waste | 2014 |
| Safe Home Rentals Limited | Real estate | 2020 |
| Safetynet Computing Limited | Information & communication | 2004 |
| Sager Summit Ltd | Real estate | 2026 |
| SAM Tyers Ltd | Construction | 2023 |
| Sambuca Consett Ltd | Hospitality | 2017 |
| Samej Ltd | Hospitality | 2023 |
| Sand and Sass Ltd | Wholesale & retail | 2021 |
| Sandford Bulk Services Limited | Water & waste | 2019 |
| Sandhu's Blackhill Golden Fish Inn Limited | Wholesale & retail | 2012 |
| Sandhu's Golden Fish Inn Limited | Wholesale & retail | 2012 |
| Sandhu's Investment Properties Limited | Real estate | 2014 |
| SAP Engineering Ltd | Professional & scientific | 2019 |
| Sarah Nails and Beauty (DH) Limited | Other services | 2019 |
| Sarnie Salon Consett Ltd | Hospitality | 2026 |
| Saru Properties Ltd | Real estate | 2024 |
| Savage Douglas Property Ltd | Real estate | 2022 |
| SB Electrical Contractors NE Ltd | Construction | 2026 |
| SB Indian Restaurant Limited | Hospitality | 2025 |
| Scott's Access Services (UK) Ltd | Administrative & support | 2017 |
| Scout Investments (NE) Limited | Financial services | 2025 |
| SD Electronic Integration & Control Ltd | Professional & scientific | 2022 |
| SDH Renewables Ltd | Construction | 2023 |
| Security Print Solutions Limited | Manufacturing | 1982 |
| Security Services International (Hereford) Limited | Administrative & support | 2001 |
| Security Services International (Holdings) Limited | Financial services | 2025 |
| Selden Roofing & Cladding Ltd | Construction | 2020 |
| Self Storage Consett & Removals Ltd | Administrative & support | 2015 |
| Sene Design Limited | Financial services | 2022 |
| Serene Mood Limited | Health & social care | 2021 |
| Setxrp Limited | Financial services | 2023 |
| SFW Management & Sporting Ltd | Real estate | 2024 |
| SG Autos Services Ltd | Wholesale & retail | 2020 |
| Shadows of Light CIC | Health & social care | 2025 |
| Sharpm Tradind Ltd | Information & communication | 2017 |
| Shorco Electrical Limited | Construction | 2008 |
| Shorco Mechanical Limited | Construction | 2021 |
| Shotley Bridge Old Town Hall Limited | Households | 2024 |
| Shotley Bridge Property Management Limited | Real estate | 2012 |
| Shotleyfoods Limited | Hospitality | 2026 |
| SHS Properties Limited | Extraterritorial | 2012 |
| Sidekick Executive Ltd | Administrative & support | 2020 |
| Sidequest WAS Taken CIC | Arts & recreation | 2025 |
| Sierra Alpha Risk Consulting Ltd | Other services | 2023 |
| SIG Management Consultancy Limited | Professional & scientific | 2014 |
| Sigma Engineering Analysis Consultants Limited | Professional & scientific | 1995 |
| SIGMA8 Ltd | Construction | 2016 |
| Silver Sunshine Consultancy Limited | Professional & scientific | 2026 |
| Silverbirch Landscapes Limited | Administrative & support | 2016 |
| Simba Promotions Limited | Arts & recreation | 2021 |
| Simon Griffiths Sculpture Limited | Wholesale & retail | 2010 |
| Simply Bows and Chairs Covers Franchising Limited | Administrative & support | 2009 |
| Simply Radiant Aesthetics Ltd | Other services | 2023 |
| Singers Bar Ltd | Hospitality | 2024 |
| Singers Enterprises Ltd | Hospitality | 2016 |
| Sirin Chef Limited | Wholesale & retail | 2023 |
| Siyam Tandoori Ltd | Administrative & support | 2019 |
| SJK Mechanical Services Limited | Manufacturing | 2010 |
| Skidmore Properties Ltd | Real estate | 2019 |
| Skin Academy NE Ltd | Health & social care | 2026 |
| Skirsgill Properties Ltd | Real estate | 2021 |
| SLD Capital Holdings Ltd | Financial services | 2024 |
| Sleep Unlimited Ltd. | Professional & scientific | 2011 |
| Slicedpear Ltd | Professional & scientific | 2022 |
| SM Bodyworx Ltd | Manufacturing | 2025 |
| Smart Match Energy Limited | Administrative & support | 2026 |
| Smartt Veterans CIC | Hospitality | 2024 |
| Smile Archery Coaching Ltd | Arts & recreation | 2012 |
| SNA Chimneys Ltd | Construction | 2018 |
| Snackfully Ltd | Wholesale & retail | 2020 |
| Snackisseur Ltd | Professional & scientific | 2020 |
| Snows Green Farm Limited | Agriculture & fishing | 2026 |
| Social 3BL Ltd | Information & communication | 2011 |
| Soffitto Limited | Other services | 2013 |
| Solar 1 Electrical Limited | Construction | 2010 |
| Solo Capital Invest Ltd | Other services | 2019 |
| Song&Media LLP | | 2014 |
| Sonic Communications Ltd | Construction | 2020 |
| Sophie Photography Events Ltd | Wholesale & retail | 2026 |
| Sorlini Holding Ltd | Financial services | 2019 |
| Southgarth Solutions Limited | Professional & scientific | 2025 |
| Southlands Garage Limited | Wholesale & retail | 2026 |