| SMA Transport Consultants Limited | Transport & logistics | 2021 |
| Smalls Contractors Limited | Agriculture & fishing | 2008 |
| Smarketing Ltd | Professional & scientific | 2024 |
| Smart 3PL Ltd | Transport & logistics | 2025 |
| Smart Auto Keys Ltd | Wholesale & retail | 2025 |
| Smart Auto Repairs SY Ltd | Wholesale & retail | 2025 |
| Smart Barber Doncaster Limited | Other services | 2025 |
| Smart Electrical Services 4 U Ltd | Construction | 2014 |
| Smart Hoist UK Ltd | Information & communication | 2023 |
| Smart Pick Deals Limited | Wholesale & retail | 2025 |
| Smart Planet Solutions Ltd | Administrative & support | 2025 |
| Smart Repair Wizard Ltd | Construction | 2024 |
| Smart Roofing & Property Maintenance Ltd | Construction | 2024 |
| Smart Support for Business Limited | Professional & scientific | 2013 |
| Smart Trans Ltd | Transport & logistics | 2025 |
| Smart Waste Limited | Water & waste | 2025 |
| Smarta Safe Solutions Limited | Professional & scientific | 2018 |
| Smartay Ltd | Wholesale & retail | 2025 |
| Smarte-Hr Consulting Services Ltd | Administrative & support | 2022 |
| Smartest Construction Ltd | Construction | 2019 |
| Smarties Parties Ltd | Extraterritorial | 2021 |
| Smartins Ltd | Information & communication | 2004 |
| Smartmove Interactive Learning Limited | Education | 2002 |
| Smarttec Systems Limited | Administrative & support | 2019 |
| Smartwork (Doncaster) Ltd | Construction | 2017 |
| Smash Audio Ltd | Administrative & support | 2026 |
| SMB Consultancy Group Limited | Administrative & support | 2016 |
| SMB Vinyl Ltd | Wholesale & retail | 2024 |
| SME Investment Capital Ltd | Professional & scientific | 2020 |
| Smellacloud Ltd | Wholesale & retail | 2019 |
| Smidell Holdings Limited | Financial services | 2021 |
| Smigo Services Ltd | Information & communication | 2022 |
| Smile Dental Palace Ltd | Health & social care | 2025 |
| Smile in a CUP Ltd | Hospitality | 2020 |
| Smile Thai Group Ltd | Financial services | 2026 |
| Smile Thai Lion Limited | Hospitality | 2026 |
| Smiley Faces Nursery Ltd | Health & social care | 2017 |
| Smith & Sons Property Ltd | Construction | 2025 |
| Smith and Smith United Limited | Professional & scientific | 2001 |
| Smith Benedict & Co Limited | Professional & scientific | 2013 |
| Smith Bros. (Caer Conan) Wholesale Limited | Wholesale & retail | 1932 |
| Smith Brothers,Rotherham Limited | Wholesale & retail | 1947 |
| Smith Craven (Yorkshire) Limited | Professional & scientific | 2022 |
| Smiths Estates Ltd | Construction | 2016 |
| Smithson Electrical Services Limited | Construction | 2014 |
| SMJ Construction Doncaster Ltd | Construction | 2016 |
| SMJ Trans Ltd | Transport & logistics | 2025 |
| SMK Construction Services (Doncaster) Ltd | Real estate | 2020 |
| SMK Realty Ltd | Real estate | 2025 |
| Smoke & Grill Ltd | Hospitality | 2024 |
| Smoke and Matches Ltd | Manufacturing | 2024 |
| Smokey's Kitchen Two Limited | Hospitality | 2025 |
| Smokey's Slices N Shakes Ltd | Hospitality | 2022 |
| Smoothstone Consultancy Ltd. | Professional & scientific | 2012 |
| SMP Plumbing & Heating Ltd | Construction | 2024 |
| SMP Property Rentals Ltd | Real estate | 2026 |
| SMR Medics Ltd | Health & social care | 2013 |
| SMT BUS and Coach Ltd | Wholesale & retail | 2024 |
| SMT57 Ltd | Real estate | 2025 |
| Smtp Ltd | Hospitality | 2025 |
| Smtxtra Ltd | Wholesale & retail | 2007 |
| Smvp Ltd | Real estate | 2021 |
| SMW Aesthetic Ltd | Other services | 2026 |
| Smyth & Sheehan Property Investments Ltd | Real estate | 2014 |
| Smyth & Stevens Property Partnership Ltd | Real estate | 2014 |
| Smyth & White Property Partnership Ltd | Real estate | 2014 |
| SN Accounting Services Limited | Professional & scientific | 2012 |
| SN Brothers Ltd | Wholesale & retail | 2024 |
| SN Collective Ltd | Hospitality | 2026 |
| Snap Transport Ltd | Transport & logistics | 2019 |
| Snapfix Auto Centre Ltd | Wholesale & retail | 2025 |
| Snapscape Photography Limited | Professional & scientific | 2025 |
| Snave Media Ltd | Professional & scientific | 2025 |
| SNAX4LIFE Ltd | Wholesale & retail | 2026 |
| SNB Installations Limited | Manufacturing | 2012 |
| SNG Wealth Management Ltd | Financial services | 2021 |
| Snivt International Ltd | Transport & logistics | 2020 |
| Snowdrop Cleaning and Co Limited | Administrative & support | 2026 |
| Snowlife Limited | Information & communication | 2014 |
| SNS QS Ltd | Construction | 2018 |
| Snug Property Services Limited | Construction | 2021 |
| SO Eco Build Limited | Construction | 2023 |
| So-Noonan Limited | Arts & recreation | 2012 |
| Soap Vintage Ltd | Wholesale & retail | 2022 |
| Soar Care & Services Limited | Administrative & support | 2024 |
| Soare Transport Limited | Transport & logistics | 2026 |
| SOB Autofix Limited | Wholesale & retail | 2025 |
| Soccer 4 Success Ltd | Education | 2012 |
| Soccer Star Connect Limited | Arts & recreation | 2024 |
| Social Accelerator Ltd | Wholesale & retail | 2025 |
| Social Beats Ltd | Hospitality | 2022 |
| Social Dreamers Ltd | Professional & scientific | 2026 |
| Social Paradigm Group Ltd | Professional & scientific | 2026 |
| Society of Ploughmen Limited (the) | Other services | 1972 |
| Sock & Co Property Solutions Limited | Real estate | 2025 |
| Soda Investments Limited | Real estate | 2023 |
| Soesystems Ltd | Construction | 2024 |
| SOF Haulage Ltd | Transport & logistics | 2023 |
| Sofa Hub Yorkshire Limited | Wholesale & retail | 2024 |
| Sofaworks Limited | Wholesale & retail | 2015 |