| Southern Dream Living Ltd | Real estate | 2026 |
| Southern Edge Contractors Ltd | Construction | 2025 |
| Southern Energy Awareness Limited | Construction | 2006 |
| Southern Entertainment Services Ltd | Arts & recreation | 2020 |
| Southern Fire Solutions Ltd | Public administration | 2017 |
| Southern GAS Services Limited | Construction | 2008 |
| Southern Glazing Contractors Ltd | Construction | 2026 |
| Southern Group Holdings Limited | Financial services | 2020 |
| Southern Industrial Solutions Limited | Construction | 2018 |
| Southern Landscaping Ltd | Administrative & support | 2019 |
| Southern Mechanical and Electrical Limited | Construction | 2015 |
| Southern Properties Lymington Ltd | Construction | 2017 |
| Southern Relocation Services Limited | Transport & logistics | 2019 |
| Southern Rendering Ltd | Construction | 2020 |
| Southern Resin Ltd | Construction | 2018 |
| Southern Services Highways Ltd | Construction | 2020 |
| Southern Smart Homes Limited | Construction | 2021 |
| Southern Specialised Services Ltd | Arts & recreation | 2018 |
| Southern Star Trading Limited | Hospitality | 2021 |
| Southern Transport Compliance Ltd | Transport & logistics | 2023 |
| Southern Tree Specialists Limited | Agriculture & fishing | 2013 |
| Southern Triumph Ltd | Wholesale & retail | 2016 |
| Southern Triumph Services Ltd | Wholesale & retail | 2016 |
| Southern Ukulele Store Ltd | Wholesale & retail | 2023 |
| Southern Ventilation Limited | Administrative & support | 2024 |
| Southface Consultancy Limited | Real estate | 2019 |
| Southface Holdings Limited | Health & social care | 2019 |
| Southface Skin Clinic Limited | Health & social care | 2010 |
| Southline Maintenance Ltd | Construction | 2026 |
| Southshore Property Holdings Ltd | Real estate | 2022 |
| Southside Developments Ltd | Construction | 2019 |
| Southside Engineering Services Limited | Financial services | 2024 |
| Southside Services Limited | Transport & logistics | 2015 |
| Southwest Retail Groups Ltd | Wholesale & retail | 2025 |
| Southwick Road Freehold Limited | Households | 2011 |
| Southwood Court Owners Limited | Households | 2018 |
| Sovereign Boat Services Limited | Manufacturing | 2003 |
| Sovereign Directors Limited | Extraterritorial | 2001 |
| Sovereign Management Group Limited | Information & communication | 2020 |
| Sovereign Secretarial Limited | Extraterritorial | 2002 |
| Sovereign Technologies Limited | Information & communication | 2017 |
| Soverin Technologies Ltd | Professional & scientific | 2019 |
| Sovrix Limited | Wholesale & retail | 2025 |
| Sowemates Ventures Limited | Real estate | 2026 |
| SP Global Care Ltd | Health & social care | 2024 |
| SP Global Motors Ltd | Wholesale & retail | 2023 |
| SP Trading Ltd | Professional & scientific | 2026 |
| SP0RTSNEST Limited | Information & communication | 2023 |
| Spa Treatments at Hengistbury Ltd | Other services | 2022 |
| Space & Time Corporate Trustee Limited | Financial services | 2018 |
| Space & Time Group Holdings Limited | Financial services | 2021 |
| Space & Time Group Limited | Financial services | 2018 |
| Space & Time Media Limited | Professional & scientific | 1991 |
| Space and Time Holdings Limited | Financial services | 2016 |
| Space Industries Ltd | Construction | 1991 |
| Spacegrade Composite Engineering Limited | Manufacturing | 2017 |
| Spanish Homes Limited | Real estate | 2001 |
| Spanishlegalhomes.Com Limited | Extraterritorial | 2013 |
| Sparked Electrical Contractors Limited | Construction | 2015 |
| Sparkeze Ltd | Wholesale & retail | 2020 |
| Sparkford Hill Limited | Construction | 2020 |
| Sparkle and Clean Services Limited | Administrative & support | 2023 |
| Sparkly Space Cleaning Services Ltd | Administrative & support | 2026 |
| Sparkone Electrical Ltd | Extraterritorial | 2024 |
| Sparks Joy Electrical Ltd | Construction | 2025 |
| Sparkwell Limited | Real estate | 2005 |
| Sparkys Electrical Limited | Wholesale & retail | 2005 |
| SPC Education Services Limited | Education | 2022 |
| SPC IT Limited | Information & communication | 2012 |
| Spec OPS Airsoft Limited | Arts & recreation | 2013 |
| Specialised Products (Western) Limited | Wholesale & retail | 1951 |
| Specialised Site Services Limited | Construction | 2020 |
| Specialist Cosmetic Care Limited | Health & social care | 2021 |
| Specialist Motorsport Ltd | Education | 2023 |
| Specialists in Local Councils (Silc) Ltd | Professional & scientific | 2025 |
| Species Ecological Consultancy Ltd | Professional & scientific | 2011 |
| Species Limited | Professional & scientific | 2011 |
| Spectacular Pizza Ltd | Hospitality | 2026 |
| Spectrum Payroll Solutions Ltd | Other services | 2021 |
| Spectrumlife Support Services Limited | Health & social care | 2026 |
| Speed 9570 Limited | Hospitality | 2003 |
| Speedbird Property and Rentals Limited | Real estate | 2020 |
| Speedy FLY Ltd | Transport & logistics | 2019 |
| Speedzen Limited | Transport & logistics | 2024 |
| Spencer Road (Bournemouth) Freehold Limited | Households | 2020 |
| Spetisbury Construction Limited | Construction | 1984 |
| Spetisbury Group Limited | Financial services | 2026 |
| Spetisbury Holdings Limited | Professional & scientific | 2009 |
| Spetisbury View Limited | Construction | 2020 |
| Spherative Limited | Manufacturing | 2024 |
| Spice Tadka and Beyond Ltd | Manufacturing | 2025 |
| Spice UP Your Marketing Ltd | Professional & scientific | 2025 |
| Spick Span Shine and Sparkle Ltd | Other services | 2015 |
| Spike Global Limited | Information & communication | 2011 |
| Spiller Door Controls Holdings Limited | Wholesale & retail | 2022 |
| Spiller’S Property Solutions Ltd | Construction | 2024 |
| Spindle Close Management Company Limited | Real estate | 2002 |
| Spinnakers Property Company Limited | Households | 1993 |
| Spinning Wheel Music Ltd | Information & communication | 2020 |
| Spiritual-Sky Limited | Wholesale & retail | 2012 |