| Smart Options Ltd | Administrative & support | 2012 |
| Smart PIG Ltd | Information & communication | 2025 |
| Smart Pro (Mobile Vehicle Cosmetic Repairs) Limited | Wholesale & retail | 2013 |
| Smartbuild Innovations Ltd | Manufacturing | 2018 |
| Smartcreate Ltd | Manufacturing | 2026 |
| Smartec Solutions Ltd | Construction | 2018 |
| Smarter Sites Ltd | Information & communication | 2023 |
| Smartflow Finance Limited | Professional & scientific | 2025 |
| Smartgas Heating & Plumbing LTN Ltd | Construction | 2023 |
| Smartrent Properties Ltd | Real estate | 2023 |
| Smarttasker Limited | Information & communication | 2015 |
| Smartwage Ltd | Information & communication | 2020 |
| Smash-It Games Ltd | Arts & recreation | 2024 |
| SMB (Suffolk) Ltd | Wholesale & retail | 2024 |
| SMD Accounts LLP | | 2020 |
| SME Loan Hub Ltd | Extraterritorial | 2023 |
| SME Web Designs Ltd | Information & communication | 2025 |
| Smile Whitening Ltd | Other services | 2024 |
| Smiledove Travels and Tours UK Ltd | Administrative & support | 2026 |
| Smilegene Ltd | Wholesale & retail | 2024 |
| Smiley Towers Ltd | Real estate | 2022 |
| Smit Lettings Limited | Administrative & support | 2016 |
| Smith&Co Watches Ltd | Wholesale & retail | 2019 |
| Smith-Potts Properties Ltd | Real estate | 2024 |
| Smithson's Bakery Co Ltd | Wholesale & retail | 2026 |
| SML Services Ltd | Professional & scientific | 2025 |
| Smnr Property Limited | Real estate | 2017 |
| Smoke House Inns Limited | Hospitality | 1974 |
| Smoking Barrel Store Ltd | Wholesale & retail | 2020 |
| SMS Enterprises (Suffolk) Limited | Hospitality | 2024 |
| Smtj Interim Ltd. | Professional & scientific | 2013 |
| Smyleco Limited | Wholesale & retail | 2019 |
| Snap Heaven Ltd | Arts & recreation | 2026 |
| Snap ME Pretty Ltd | Professional & scientific | 2024 |
| Snap the Day Ltd | Professional & scientific | 2024 |
| Snapswing Limited | Wholesale & retail | 2025 |
| Sneasoft Ltd | Information & communication | 2024 |
| Sneddon Logistics Ltd | Transport & logistics | 2018 |
| Sniffables Ltd | Wholesale & retail | 2025 |
| Snob Monkey Limited | Information & communication | 2012 |
| Snoozem Ltd | Wholesale & retail | 2024 |
| Snowfunk Ltd | Manufacturing | 2023 |
| Snug Peas Limited | Wholesale & retail | 2023 |
| Snugly Auto Limited | Wholesale & retail | 2025 |
| Snugly Logistics Limited | Transport & logistics | 2024 |
| Snugvolt Ltd | Wholesale & retail | 2025 |
| Snuspouch.Uk Limited | Wholesale & retail | 2025 |
| Snuzzleberry Ltd | Wholesale & retail | 2025 |
| SO Bar Leisure Limited | Hospitality | 2024 |
| SO Labels Ltd | Other services | 2017 |
| Soaden Limited | Wholesale & retail | 2022 |
| Soar Valley Properties Limited | Real estate | 2019 |
| Soaring Hillman Ltd | Construction | 2025 |
| Soaring Seagull Ltd | Financial services | 2025 |
| Sobenan Property Limited | Real estate | 2007 |
| Sober Points Ltd | Information & communication | 2025 |
| Social 27 Ltd | Information & communication | 2026 |
| Social Freak Ltd | Wholesale & retail | 2023 |
| Social HAN Ltd | Professional & scientific | 2023 |
| Social Reach Marketing Ltd | Professional & scientific | 2017 |
| Social Selling With SAM Limited | Other services | 2018 |
| Socialiser App Ltd | Information & communication | 2026 |
| Socially Leon Limited | Information & communication | 2024 |
| Society for Urban Studies Limited | Information & communication | 2026 |
| Socium Investments Ltd | Professional & scientific | 2022 |
| Socius TF Ltd | Health & social care | 2023 |
| Socrates Olympio Ministries | Information & communication | 2014 |
| Soda Ltd | Construction | 2025 |
| Sofadog Ltd | Wholesale & retail | 2024 |
| Sofantastic Limited | Wholesale & retail | 2019 |
| Sofistick Ltd | Wholesale & retail | 2026 |
| Sofmanagements Holdings Limited | Professional & scientific | 2025 |
| Sofmanagements Limited | Professional & scientific | 2025 |
| Soft Intention Ltd | Wholesale & retail | 2025 |
| Soft Object Studio Ltd | Wholesale & retail | 2025 |
| Softenergeeks Limited | Wholesale & retail | 2017 |
| Softfrance Ltd | Information & communication | 2025 |
| Software Kent Ltd | Other services | 2024 |
| Soil Carbon Solutions Limited | Agriculture & fishing | 2020 |
| Soko Property Ltd | Real estate | 2023 |
| Soko Sourcing Ltd | Administrative & support | 2023 |
| SOL & Ebano Limited | Information & communication | 2017 |
| Sola Wellness Ltd | Wholesale & retail | 2026 |
| Solair Skin Limited | Manufacturing | 2025 |
| Solana Studios Ltd | Professional & scientific | 2026 |
| Solar Connect Ltd | Construction | 2022 |
| Solar KOI UK Ltd | Administrative & support | 2025 |
| Solar Services Ltd | Construction | 2026 |
| Solarcityafrica Ltd | Professional & scientific | 2022 |
| Solarian Ventures Limited | Wholesale & retail | 2025 |
| Solarplus (East Anglia) Limited | Construction | 2023 |
| Solarsat Limited | Information & communication | 2013 |
| Solasis Limited | Information & communication | 2023 |
| Soldoutmotorcycles Ltd | Manufacturing | 2021 |
| Soleygrail Ltd | Wholesale & retail | 2017 |
| Solid Black Ltd | Wholesale & retail | 2022 |
| Solihull Derm Doctors Ltd | Health & social care | 2023 |
| Solo Wave 2 Ltd | Real estate | 2019 |
| Solubridge Ltd | Health & social care | 2025 |
| Solumangroup Ltd | Professional & scientific | 2021 |