| Smiledrip Whitening Ltd | Other services | 2025 |
| Smiles Better Entertainment Limited | Administrative & support | 2016 |
| Smiles Healthcare Professionals (UK) Limited | Health & social care | 2013 |
| SMN Construction Ltd | Construction | 2019 |
| Smoke & Saga Ltd | Hospitality | 2025 |
| Smooth Skincare Ltd | Wholesale & retail | 2026 |
| Smoothies Limited | Hospitality | 2016 |
| Smrk Cars Ltd | Transport & logistics | 2024 |
| SMS UK Services Limited | Transport & logistics | 2017 |
| Smsbya Skin Made Smooth by Antho Ltd | Other services | 2025 |
| Smsk Ltd | Construction | 2022 |
| SMU Trading Ltd | Wholesale & retail | 2020 |
| SMV Stanca Ltd | Construction | 2016 |
| SN Renovation Ltd | Construction | 2014 |
| SN Services Ltd | Real estate | 2018 |
| Snack Point Ltd | Wholesale & retail | 2024 |
| Snack Star Limited | Hospitality | 2025 |
| Sneham Enterprises UK Limited | Wholesale & retail | 2025 |
| SNH Integration Services Ltd. | Information & communication | 2016 |
| Snhes Ltd | Health & social care | 2015 |
| SNK Building Solutions Ltd | Construction | 2022 |
| Snowmedia Consulting Limited | Information & communication | 2016 |
| SNS Interiors Ltd | Construction | 2013 |
| Snva Ltd | Construction | 2026 |
| SO Sweet Events Ltd | Hospitality | 2018 |
| Soarites & Co Limited | Real estate | 2023 |
| Sobo Clading Ltd | Construction | 2015 |
| Socialwe Solutions Ltd | Information & communication | 2021 |
| Society of African Caribbean Midwives CIC | Health & social care | 2024 |
| Sociomedia Ltd | Water & waste | 2024 |
| Socolidi Construction Ltd | Construction | 2025 |
| Sodan Limited | Health & social care | 2020 |
| Sofat Engineering Limited | Other services | 2015 |
| Sofip BL Ltd | Construction | 2020 |
| Soflana Logistics Ltd | Transport & logistics | 2025 |
| Soft Skill Studio Limited | Information & communication | 2023 |
| Softtlogistics Global Services Ltd | Transport & logistics | 2020 |
| Sohi Links Ltd | Administrative & support | 2025 |
| Sohu International Ltd | Wholesale & retail | 2024 |
| Sojogep Ltd | Health & social care | 2022 |
| Solar Accountancy Limited | Professional & scientific | 2019 |
| Solatium Supported Services Ltd | Health & social care | 2025 |
| Solbra Limited | Construction | 2019 |
| Soleinterest Ltd | Wholesale & retail | 2023 |
| Solex Solutions Ltd | Wholesale & retail | 2018 |
| Solid Source Contracting Limited | Construction | 2016 |
| Solid Trading Ltd | Wholesale & retail | 2019 |
| Solidarity Group of Friends UK Ltd | Other services | 2026 |
| Solo Initiative C.I.C. | Hospitality | 2025 |
| Sololina Ltd | Health & social care | 2015 |
| Solomonar Construction Ltd | Construction | 2024 |
| Solomun 2017 Ltd | Construction | 2021 |
| Solt Collective CIC | Education | 2026 |
| Solution Inn Ltd | Information & communication | 2013 |
| Solutions 21 Limited | Construction | 2017 |
| Solutions Media Limited | Information & communication | 2025 |
| Solve Management Ltd | Professional & scientific | 2013 |
| Solventra Limited | Administrative & support | 2025 |
| Solvix Media Ltd | Information & communication | 2026 |
| SOM Contractors Ltd | Construction | 2021 |
| SOM Engineers Ltd | Construction | 2011 |
| Somchibi Limited | Health & social care | 2015 |
| Sonia Beauty Clinic Ltd | Other services | 2026 |
| Sonic Estates&Assets Management Ltd | Real estate | 2021 |
| Sonic Group Ltd | Real estate | 2023 |
| Sonu Construction Ltd | Construction | 2018 |
| Sony Shopfronts Limited | Construction | 2022 |
| Sooda Ltd | Wholesale & retail | 2025 |
| Soothing Scents Wholesale Ltd | Wholesale & retail | 2025 |
| Sophisticated Design Ltd | Professional & scientific | 2018 |
| Sophos Medos Limited | Professional & scientific | 2022 |
| Sorna F F Ltd | Administrative & support | 2019 |
| Sorsel Limited | Construction | 2014 |
| Sosa Limited | Wholesale & retail | 2018 |
| Sosasldn Ltd | Information & communication | 2022 |
| Sosoliso Transport Ltd | Transport & logistics | 2018 |
| Sought After Services Ltd | Information & communication | 2024 |
| Soulace App Ltd | Financial services | 2025 |
| Soulecare and Help Ltd | Administrative & support | 2021 |
| Soulhousemusic Ltd | Information & communication | 2016 |
| Source Code Solutions Ltd | Information & communication | 2015 |
| Source Workers Limited | Administrative & support | 2025 |
| Sourcedbyat Ltd | Wholesale & retail | 2025 |
| Sourceking Ltd | Wholesale & retail | 2019 |
| South East Automotive (Service) Limited | Wholesale & retail | 2007 |
| South Eastern Tanker Services Group Limited | Financial services | 2021 |
| South Eastern Tanker Services Limited | Other services | 1987 |
| SOV Homes Ltd | Real estate | 2023 |
| Sovereign & Bale Ltd | Other services | 2013 |
| Soyan Decorating Limited | Other services | 2015 |
| SP Landscapes & Services Limited | Construction | 2017 |
| SP UK Property Ltd | Real estate | 2025 |
| SPACECREA8 Ltd | Construction | 2026 |
| Spade Integrated Systems UK Ltd | Information & communication | 2026 |
| Spaoptions Ltd | Other services | 2016 |
| Spark-Exl Ltd | Wholesale & retail | 2024 |
| Sparkle OMS Cleaning Limited | Administrative & support | 2024 |
| Sparkle Squad FM Ltd | Administrative & support | 2022 |
| Sparklean Cleaning Services Ltd | Administrative & support | 2015 |
| Sparkles & Glitz Ltd | Administrative & support | 2026 |