| Skybridge Ventures Ltd | Wholesale & retail | 2025 |
| Skyfield Partners Ltd | Real estate | 2025 |
| Skylight Trader Ltd | Transport & logistics | 2025 |
| Skylines Properties Ltd | Real estate | 2020 |
| Skypluse Ltd | Energy | 2025 |
| SL Data Cabling Limited | Manufacturing | 2014 |
| Slash&Co Ltd | Wholesale & retail | 2025 |
| Sleda Ltd | Construction | 2025 |
| Sliding Windows Sliding Doors + More Ltd | Construction | 2012 |
| SM Lofts & Extensions Ltd | Construction | 2023 |
| SM Sons Transport Ltd | Wholesale & retail | 2025 |
| SMA Networks Ltd | Information & communication | 2018 |
| Smaart Trading Ltd | Transport & logistics | 2021 |
| Small Boxes Limited | Manufacturing | 2011 |
| Smart Business Pro Ltd | Administrative & support | 2018 |
| Smart Investment Life Ltd | Real estate | 2025 |
| Smart IT Consultants Ltd | Information & communication | 2025 |
| Smart Route Systems Ltd | Administrative & support | 2025 |
| Smart School of Driving Ltd | Education | 2023 |
| Smart Universe Limited | Wholesale & retail | 2026 |
| Smart Wash Trading Ltd | Other services | 2019 |
| Smartec (UK) Limited | Wholesale & retail | 2010 |
| Smarterwork.Com Limited | Extraterritorial | 1999 |
| Smartinger Ltd | Wholesale & retail | 2022 |
| Smartkit Communications Ltd | Information & communication | 2024 |
| Smartkookie Ltd | Information & communication | 2026 |
| Smashah Medical Limited | Health & social care | 2016 |
| Smashb Limited | Hospitality | 2026 |
| SMC Incentives Limited | Manufacturing | 2010 |
| SMD2016 Trading Ltd | Transport & logistics | 2016 |
| SME Cloud Solutions Ltd | Information & communication | 2015 |
| Smhs Group Ltd | Hospitality | 2025 |
| Smile Excellence Care Ltd | Health & social care | 2022 |
| Smilovski Drylining Ltd | Construction | 2019 |
| SMK Solutions Ltd | Professional & scientific | 2025 |
| Smoke Mart Ltd | Wholesale & retail | 2012 |
| SMR Foods Ltd | Hospitality | 2015 |
| Smurf Services Ltd | Construction | 2024 |
| SNA Community Transport CIC | Transport & logistics | 2024 |
| SNA Transport Limited | Transport & logistics | 2005 |
| Snack WIZ Vending Ltd | Wholesale & retail | 2025 |
| Snackss Ltd | Hospitality | 2025 |
| Snan Trading Ltd | Financial services | 2020 |
| Snapmarket Ltd | Wholesale & retail | 2025 |
| Snapz Tees Ltd | Wholesale & retail | 2025 |
| Snowik Holding Ltd | Financial services | 2025 |
| Snowik Online Ltd | Construction | 2025 |
| Soapbox Events Ltd | Professional & scientific | 2026 |
| Soapstone Alchemy Limited | Manufacturing | 2021 |
| Soccer Equipment Limited | Manufacturing | 2025 |
| Social Injustice Limited | Arts & recreation | 2023 |
| Social Ltd | Extraterritorial | 2025 |
| Sofie Faris Ltd | Wholesale & retail | 2021 |
| Sofineti Ltd | Transport & logistics | 2018 |
| Soft Accounting Solutions Limited | Professional & scientific | 2007 |
| Soft Life Enterprises Ltd | Administrative & support | 2023 |
| Soft Ltd | Information & communication | 2024 |
| Softora Ltd | Wholesale & retail | 2025 |
| Sokids Ltd | Extraterritorial | 2016 |
| Solace East Ltd | Real estate | 2021 |
| Solar Accountancy Services Limited | Professional & scientific | 1997 |
| Solar Accounts Services Limited | Professional & scientific | 2014 |
| Solid Clean Ltd | Administrative & support | 2024 |
| Solidsocial Ltd | Information & communication | 2022 |
| Solion Estates Ltd | Real estate | 2025 |
| SOLO1 Ltd | Construction | 2022 |
| Soloar Transport Ltd | Transport & logistics | 2022 |
| Solos Consulting Ltd | Information & communication | 2020 |
| Solutioremote Ltd | Professional & scientific | 2023 |
| Somshexuriel Ltd | Health & social care | 2020 |
| Sonim Ltd | Construction | 2024 |
| Sonus Properties Ltd | Administrative & support | 2017 |
| Sony Traders Ltd | Other services | 2020 |
| Sonya Plants and Flowers Ltd | Professional & scientific | 2025 |
| Sophisticated Innovations Ltd | Information & communication | 2018 |
| Sophisticated Languages Ltd | Professional & scientific | 2023 |
| Soul Pine Ltd | Information & communication | 2023 |
| Soundcrest Audio Productions Ltd | Information & communication | 2025 |
| Sourcedbytizz Ltd | Wholesale & retail | 2026 |
| South London Community Sport&Wellbeing CIC | Education | 2026 |
| South Play Limited | Administrative & support | 2007 |
| South Street Retro Limited | Wholesale & retail | 2024 |
| South-M Construction Ltd | Construction | 2017 |
| Southend (UK) Ltd | Construction | 2008 |
| Southerland Developments Ltd | Real estate | 2021 |
| Southsea Fish Bar Surrey Limited | Hospitality | 2018 |
| Southside Union Limited | Hospitality | 2018 |
| Sovereign Hire Service UK Ltd | Transport & logistics | 2015 |
| SP Constructions (Surrey) Ltd | Construction | 2022 |
| Space for Change Design Ltd | Professional & scientific | 2019 |
| Spah Holdings Ltd | Financial services | 2025 |
| Spark Holds Ltd | Financial services | 2024 |
| Spark UK Property Investment Ltd | Real estate | 2023 |
| Speech and Language Launchpad Limited | Health & social care | 2025 |
| Speed FIX Tyres Ltd | Wholesale & retail | 2022 |
| Speedway E-Store Limited | Administrative & support | 2022 |
| Speedx Crafts Ltd | Manufacturing | 2024 |
| Spepro Limited | Real estate | 2016 |
| SPF Surfacing and Maintenance Ltd | Construction | 2022 |
| Spice Palace UK Ltd | Hospitality | 2018 |