| Solano Limited | Wholesale & retail | 2025 |
| Solar Allover Ltd | Construction | 2023 |
| Solar Distribution Solutions Limited | Energy | 2025 |
| Solar Plus Yorkshire Limited | Construction | 2010 |
| Solar Transport Systems Ltd | Professional & scientific | 2012 |
| Soldiers on SET Ltd | Information & communication | 2025 |
| Solem Construction Limited | Construction | 2014 |
| Solenco Limited | Wholesale & retail | 1998 |
| Solentherapy Ltd | Wholesale & retail | 2026 |
| Solids Handling and Processing Association Limited | Other services | 1982 |
| Solinear Holdings Limited | Professional & scientific | 2017 |
| Solis Property Management Limited | Real estate | 2021 |
| Solo Fencing Systems UK Ltd | Construction | 2006 |
| Solocad Limited | Information & communication | 1997 |
| Solutioncraft Limited | Information & communication | 2016 |
| SOLUTIONS2SUCCESS Ltd | Professional & scientific | 2007 |
| Solve & Evolve Limited | Information & communication | 2022 |
| Solway View (Workington) Management Company Limited | Households | 2017 |
| Soma Health and Wellness (UK) Limited | Health & social care | 2026 |
| Soma Solutions Ltd | Construction | 2026 |
| Somerley VAT Ltd | Professional & scientific | 2019 |
| Somerton Whitfield Limited | Professional & scientific | 2018 |
| Somewhere in a Small World Limited | Arts & recreation | 2019 |
| Sonas Consulting Ltd | Professional & scientific | 2020 |
| Sonder Women's Theatre Ltd | Arts & recreation | 2023 |
| Sonny's of York Ltd | Wholesale & retail | 2019 |
| Sooty the Sweeps (York) Ltd | Administrative & support | 2025 |
| Sophie Charles Limited | Wholesale & retail | 2014 |
| Sophie Nicholls Ltd | Information & communication | 2020 |
| Sophie Watkins Limited | Professional & scientific | 2021 |
| Soquietus Limited | Information & communication | 2021 |
| Sora Workshop Ltd | Wholesale & retail | 2025 |
| Sorbus Properties Ltd | Real estate | 2017 |
| Sorcery Limited | Information & communication | 2004 |
| Sorrell (York) Limited | Construction | 1957 |
| Sorrell Plant & Transport Limited | Real estate | 1955 |
| Sotec UK Limited | Professional & scientific | 2010 |
| Soul Forge Studios Ltd | Information & communication | 2024 |
| Soul Holdings Ltd | Hospitality | 2018 |
| Soul Hydrate Ltd | Wholesale & retail | 2024 |
| Soul Organic Limited | Wholesale & retail | 2018 |
| Sound Equine Limited | Professional & scientific | 2008 |
| Sound Practice Business Services Limited | Professional & scientific | 2024 |
| Soundproofbox International Ltd | Education | 2026 |
| Soundscape Radio Productions Limited | Information & communication | 2006 |
| Soundsgoodapp Limited | Information & communication | 2026 |
| Soundstagenorth Limited | Manufacturing | 2017 |
| Source a Salon Specialist Limited | Other services | 2023 |
| Source Certain Operations UK Limited | Professional & scientific | 2015 |
| Sourcemechanic Ltd | Information & communication | 2022 |
| South Acre Farming Limited | Agriculture & fishing | 2011 |
| South Bank Avenue Management Company Limited | Households | 2007 |
| South Bank Property Group (Investments) Limited | Real estate | 2024 |
| South Bucks Medical Services Ltd | Health & social care | 2019 |
| South Carolina Enterprises Ltd | Real estate | 2018 |
| South Coast Bathrooms Ltd | Wholesale & retail | 2012 |
| South Garth Ltd | Professional & scientific | 2024 |
| South Hambleton and Ryedale Primary Care Network Limited | Health & social care | 2024 |
| South Heslington Management Limited | Households | 1987 |
| South Hetton Development Limited | Real estate | 2017 |
| South Spice Ltd | Hospitality | 2024 |
| Southbank Homes (Yorkshire) Ltd | Construction | 2017 |
| Southbank Pest Control Ltd | Water & waste | 2019 |
| Southbank Racing Ltd | Arts & recreation | 2014 |
| Southcoates Dental Limited | Health & social care | 2025 |
| Southfield Consulting Limited | Real estate | 2004 |
| Southfield Holiday Park Limited | Construction | 2024 |
| Southfield Systems Limited | Information & communication | 2000 |
| Southfield Taxation Services Limited | Professional & scientific | 2018 |
| Southfields (Cheshire) Limited | Extraterritorial | 2006 |
| Southlands Grange (Bedale) Management Company Ltd | Households | 2023 |
| Southlands Limited | Construction | 2001 |
| Southlands Service Centre Limited | Wholesale & retail | 2001 |
| Southwell Wind Farm Limited | Energy | 2011 |
| Sovereign Build Limited | Construction | 2014 |
| Sovereign House (YO26) RTM Company Limited | Households | 2025 |
| Sovereign Kilnwick Limited | Construction | 2025 |
| Sovereign Property (Yorkshire) Limited | Extraterritorial | 2015 |
| Sowray Livestock Limited | Agriculture & fishing | 1995 |
| SP1 Cctv and Electrical Solutions Ltd | Construction | 2021 |
| Spa Contract Cleaners (Yorkshire) Limited | Administrative & support | 2015 |
| Spa Properties (GB) Limited | Real estate | 2008 |
| Spa Unique Ltd | Manufacturing | 2019 |
| Spaace Group Ltd | Professional & scientific | 2021 |
| Space Chimp Ltd | Real estate | 2017 |
| Space for Mothers CIC | Health & social care | 2026 |
| Space LAB Ventures Ltd | Education | 2024 |
| Space York CIC | Administrative & support | 2022 |
| Space&Cohair Ltd | Other services | 2025 |
| SPACE4 Limited | Construction | 1999 |
| Spaces + Places Ltd | Administrative & support | 2020 |
| Spanish Farm Limited | Real estate | 2018 |
| Spare Handle Ltd | Professional & scientific | 2020 |
| Spark Arts Ltd | Real estate | 2024 |
| Spark Community Ltd | Financial services | 2024 |
| Spark of Madness Limited | Professional & scientific | 2003 |
| Spark York C.I.C. | Real estate | 2016 |
| Sparkle in the Sun Ltd | Wholesale & retail | 2023 |
| Sparkle Recruitment Ltd | Administrative & support | 2014 |
| Sparklife Electrical Installations Limited | Construction | 2022 |