| Samuel Advisory Ltd | Financial services | 2019 |
| Samuel Jade Limited | Administrative & support | 2001 |
| SAN Assets Ltd | Real estate | 2021 |
| SAN Sutton Ltd | Real estate | 2023 |
| Sand My Floors Ltd | Construction | 2018 |
| Sandgrain Ltd | Administrative & support | 2010 |
| SANDHU626 Ltd | Transport & logistics | 2025 |
| Sandosoft Tech Limited | Information & communication | 2015 |
| Sandown Court Limited | Households | 2004 |
| Sandy Lane Projects Limited | Professional & scientific | 2015 |
| Sanini Ltd | Other services | 2017 |
| Sanitary Appliances Limited | Wholesale & retail | 1990 |
| Sanoor Limited | Manufacturing | 2019 |
| Sanspeed Solutions Limited | Information & communication | 2004 |
| Sanvee Technologies UK Ltd | Information & communication | 2015 |
| Sap-Icon Software Consultancy Services Ltd | Information & communication | 2016 |
| Sapien Medical Limited | Manufacturing | 2023 |
| Sapienta Healthcare Strategies Ltd | Professional & scientific | 2007 |
| Sapphire DCO One Limited | Professional & scientific | 1992 |
| Sapphire DCO Twelve Limited | Professional & scientific | 1923 |
| Sapphire Stone Ltd | Real estate | 2025 |
| SAR GD Ltd | Information & communication | 2026 |
| Sara Tasty Limited | Hospitality | 2019 |
| Sarah's Spice Ltd | Hospitality | 2023 |
| Sarandipity Limited | Real estate | 2025 |
| Saraswathy Retail Ltd | Wholesale & retail | 2026 |
| Saraswati BP Limited | Information & communication | 2016 |
| Saravanan Property Ltd | Real estate | 2025 |
| Sard Ltd | Real estate | 2024 |
| Sarfliek Capital Limited | Professional & scientific | 2022 |
| Saris-Uk Ltd | Wholesale & retail | 2019 |
| Sarish Invest Ltd | Households | 2024 |
| Sarish Ltd | Real estate | 2003 |
| SAS Build Surrey Ltd | Other services | 2026 |
| SAS Stumps Ltd | Administrative & support | 2023 |
| SAS Waste Limited | Water & waste | 1999 |
| Sashdecorators Ltd | Construction | 2014 |
| Sathaga Limited | Information & communication | 2016 |
| Sathees Civil Engineering Ltd | Construction | 2018 |
| Satin IVY Laundry Service Limited | Wholesale & retail | 2002 |
| Saturn Structures Ltd | Construction | 2026 |
| Sausage Ltd | Information & communication | 2001 |
| Saxon and Norman House Management Company Limited | Real estate | 1993 |
| Saxon Electrical Ltd | Construction | 2018 |
| Sayi Sanaa Ltd | Information & communication | 2016 |
| Sayitframed Ltd | Wholesale & retail | 2025 |
| Sazan Health Consulting Ltd | Health & social care | 2026 |
| Sazz 786 Ltd | Real estate | 2023 |
| SB Accountax Ltd | Professional & scientific | 2014 |
| SB Property Enterprises Ltd | Real estate | 2023 |
| SBB Catering Ltd | Hospitality | 2019 |
| Sbba Ltd | Health & social care | 2025 |
| Sbee Ltd | Real estate | 2016 |
| SBK Contractors Ltd | Construction | 2010 |
| SBL Surrey Ltd | Administrative & support | 2014 |
| SBT Infotech Limited | Information & communication | 2014 |
| SC Skills Limited | Administrative & support | 2008 |
| Scaffoldesign Ltd | Professional & scientific | 2020 |
| Scaffolding Access Inspections Limited | Construction | 2022 |
| Scafform-Design Ltd | Professional & scientific | 2020 |
| Scale Brick Ltd | Real estate | 2025 |
| Scan Sell Ltd | Wholesale & retail | 2025 |
| Scankapp Ltd | Information & communication | 2018 |
| SCG Engineers PTE Ltd | Construction | 2021 |
| Schnaider Limited | Wholesale & retail | 2022 |
| Schua Ltd | Health & social care | 2016 |
| Schwetz Limited | Construction | 2017 |
| Scinstalls Ltd | Construction | 2022 |
| Scko Ltd | Real estate | 2024 |
| Sconrail UK Limited | Professional & scientific | 2009 |
| Scoobie Dogs Ltd | Other services | 2024 |
| Scripted Rituals Limited | Hospitality | 2026 |
| Scroll Works Media Limited | Administrative & support | 2003 |
| SCS Healthcare Consulting Ltd | Health & social care | 2026 |
| Scs-Co Ltd | Extraterritorial | 2021 |
| Scsm Limited | Construction | 2001 |
| SD Fire Solutions Ltd | Public administration | 2017 |
| SD Mansfield Consultancy Limited | Financial services | 2024 |
| SDC Heating Services Limited | Construction | 2011 |
| SDG Property Investments Ltd | Real estate | 2026 |
| SDH (Social Determinants of Health)-Insights Limited | Education | 2012 |
| Sdmr FM Services Limited | Administrative & support | 2024 |
| SDP Services Retail Ltd | Wholesale & retail | 2022 |
| SDS Construction Ltd | Construction | 2008 |
| SDS Furniture Ltd | Manufacturing | 2023 |
| Sea Racing Teamco 1 Ltd | Arts & recreation | 2024 |
| Seabird Technologies Limited | Manufacturing | 2020 |
| Seaford Connect Limited | Wholesale & retail | 2021 |
| Seager Art Limited | Wholesale & retail | 2020 |
| Seale Property Holdings Limited | Real estate | 2020 |
| Seamless Co Limited | Households | 2023 |
| Sean Child Garden Landscape Design Limited | Other services | 2021 |
| Sean Mcinnes Sports Coaching Limited | Arts & recreation | 2012 |
| Sean Walter Scaffolding (Surrey) Ltd | Construction | 2017 |
| Seaway 7 Treasury Limited | Professional & scientific | 2022 |
| Seaway 7 UK Limited | Transport & logistics | 2011 |
| Sebnat Global Properties Ltd | Real estate | 2018 |
| Secure Access Scaffolding (London) Ltd | Construction | 2020 |
| Secure Cloudnet Ltd | Information & communication | 2014 |
| Securities Finance Tech Limited | Information & communication | 2025 |