| Smith Ecommerce Limited | Wholesale & retail | 2023 |
| Smith Griffiths Group Limited | Construction | 2025 |
| Smith's Distribution Limited | Transport & logistics | 1993 |
| Smiths & Rose Ltd | Wholesale & retail | 2021 |
| Smiths ELS Limited | Construction | 2017 |
| Smiths of Walsall Ltd | Manufacturing | 2003 |
| SMK Group Ltd | Wholesale & retail | 2023 |
| Smoked&Smashedwalsall Ltd | Hospitality | 2026 |
| Smooth Car Sales Ltd | Wholesale & retail | 2019 |
| SMP Consultants Ltd | Other services | 2018 |
| SMR Homes Limited | Financial services | 2021 |
| SMS Walsall Investment Ltd | Real estate | 2026 |
| SMT Merchandise Limited | Manufacturing | 1985 |
| SN Developments Ltd | Professional & scientific | 2026 |
| Snap Digitized Ltd | Transport & logistics | 2024 |
| Snapper Fish Bar Limited | Hospitality | 2023 |
| Snappy Response Couriers Ltd | Transport & logistics | 2024 |
| Snappy Response Waste Ltd | Water & waste | 2024 |
| Snbd Limited | Professional & scientific | 2019 |
| SND Homes Ltd | Administrative & support | 2025 |
| Snehajai Consulting Ltd | Information & communication | 2024 |
| Sneyd Transport Ltd | Transport & logistics | 2019 |
| SNI Hospitality Ltd | Hospitality | 2021 |
| SNI Limited | Information & communication | 2024 |
| SNK Hospitality Ltd | Hospitality | 2022 |
| Snooze Limited | Wholesale & retail | 2019 |
| Snooze Properties Ltd | Hospitality | 2024 |
| Snoozopia Ltd | Wholesale & retail | 2020 |
| SNP House Ltd | Wholesale & retail | 2025 |
| SNS Works Limited | Other services | 2020 |
| Snsc Properties Limited | Real estate | 2021 |
| Snsc Solutions Limited | Wholesale & retail | 2025 |
| Snuggle Pets Dog Gear Ltd | Wholesale & retail | 2026 |
| SO Workwear and Apparel Limited | Manufacturing | 2024 |
| Soccerwarriors Academy Ltd | Education | 2025 |
| Social Chaos Ltd | Professional & scientific | 2025 |
| Social Impact Works Ltd | Other services | 2024 |
| Social Stamp Ltd | Extraterritorial | 2020 |
| Socialcareassessments Ltd | Health & social care | 2022 |
| Socket Fixer Ltd | Manufacturing | 2020 |
| Socketfast Ltd | Wholesale & retail | 2010 |
| Soconveyancing Ltd | Professional & scientific | 2019 |
| Sodecor Ltd | Construction | 2020 |
| Sodhi Transport Ltd | Transport & logistics | 2024 |
| SOFA1 Ltd | Wholesale & retail | 2019 |
| Sofbella Ltd | Construction | 2022 |
| Sofia Driver Limited | Transport & logistics | 2020 |
| Sofia Qayyum Ltd | Other services | 2019 |
| Sofique Ltd | Manufacturing | 2026 |
| Sofix Logistics Ltd | Construction | 2025 |
| Softcentric Limited | Professional & scientific | 2013 |
| Softhands Solutions Limited | Wholesale & retail | 2009 |
| Sohans Accountants Limited | Professional & scientific | 2019 |
| Sohans Holdings Limited | Financial services | 2023 |
| Sohans Properties Limited | Real estate | 2016 |
| Sohaya Visions Limited | Arts & recreation | 2015 |
| Soho Enterprises (UK) Limited | Wholesale & retail | 2014 |
| Sokhal Properties Ltd | Real estate | 2024 |
| Solar Aircon Limited | | 1978 |
| Solar Cleaning Facilities Limited | Other services | 2003 |
| Solar Eclipse Energy Solutions Ltd | Manufacturing | 2025 |
| Solihull Investments Ltd | Real estate | 2018 |
| Solink Educational Consultancy Ltd | Education | 2024 |
| Solo Heating Services Limited | Construction | 2018 |
| Solomons Legal Services Limited | Administrative & support | 2023 |
| Solona Properties Ltd | Hospitality | 2025 |
| Solution Jewellers Limited | Other services | 2024 |
| Solve Global Limited | Professional & scientific | 2020 |
| Solve Housing Limited | Other services | 2021 |
| Solve: the Centre for Youth Violence and Conflict CIC | Professional & scientific | 2020 |
| Solviture Ltd | Financial services | 2025 |
| Somal Construction (UK) Ltd | Construction | 2019 |
| Somborne Chalk Quarry Limited | Transport & logistics | 1968 |
| Somerford Forge Properties Ltd | Real estate | 2019 |
| Somersal Cottages Limited | Hospitality | 2021 |
| Somerset Hill Ltd | Information & communication | 2020 |
| Somerville Boulevard Limited | Administrative & support | 2014 |
| Sona Distributors Limited | Wholesale & retail | 2025 |
| Sona Parfums Ltd | Wholesale & retail | 2024 |
| Sonemat Limited | Manufacturing | 2005 |
| Sonotherapy Ltd | Health & social care | 2023 |
| Sophie Happy Hearts Ltd | Health & social care | 2024 |
| Sophie Mariette Consulting Ltd | Health & social care | 2017 |
| Sophie-Joy Ltd | Health & social care | 2025 |
| Sorian Consulting Limited | Information & communication | 2020 |
| Sorinteq (Commercial) Ltd | Other services | 2024 |
| SOS Commissioning Limited | Professional & scientific | 2006 |
| SOS Scaffolding Limited | Construction | 2008 |
| Soul Revival Foundation | Information & communication | 2020 |
| Soulie Pilates Ltd | Arts & recreation | 2025 |
| Soulmend Ltd | Wholesale & retail | 2025 |
| South Cannock Farm Secure Dog Walking Limited | Other services | 2024 |
| South Staffordshire Limited | Professional & scientific | 2001 |
| South Staffs Commercials Limited | Real estate | 1996 |
| South Staffs Investments Limited | Real estate | 2018 |
| South Staffs Properties Limited | Real estate | 1996 |
| South Walsall Community Services Limited | Health & social care | 2015 |
| Southbrighten Ltd | Professional & scientific | 2022 |
| Southland Holdings Ltd | Administrative & support | 2025 |
| Soverna Ltd | Information & communication | 2025 |