| Seiha Consulting Limited | Professional & scientific | 2014 |
| Seisay Construction Management Limited | Construction | 2015 |
| Selectasine Serigraphics Limited | Wholesale & retail | 2010 |
| Self Operated Storage (Oxford) Limited | Other services | 1987 |
| Sellen Property Services Ltd | Construction | 2020 |
| Sellin Consulting LLP | | 2021 |
| Selling Savvy Limited | Other services | 2020 |
| Selmar Maritime Consultants Limited | Administrative & support | 2001 |
| Semaphore Freehold Property Ltd | Real estate | 2026 |
| Sempero Flowers Limited | Wholesale & retail | 2026 |
| SEN Viet Quan Guildford Ltd | Hospitality | 2025 |
| Send Estates Limited | Real estate | 2024 |
| Send Hill Studios Ltd | Arts & recreation | 2015 |
| Sendbeacon Ltd | Education | 2026 |
| Sens-Tech Limited | Manufacturing | 1960 |
| Senturion Fitness Coaching C.I.C. | Other services | 2023 |
| Sequoia Spring Ltd | Real estate | 2018 |
| Sequoia Yoga Ltd | Arts & recreation | 2023 |
| Seraphos Limited | Professional & scientific | 2020 |
| Serengeti Property Limited | Real estate | 2022 |
| Serenity Trade Ltd | Transport & logistics | 2025 |
| Sermo Telecom Limited | Information & communication | 2009 |
| Servalan Ltd | Extraterritorial | 2013 |
| Serveo Industria UK Ltd | Manufacturing | 2022 |
| Serverscom UK Ltd | Information & communication | 2019 |
| Service 4 Service Limited | Wholesale & retail | 1996 |
| Servicetecnic U.K. Limited | Wholesale & retail | 1998 |
| SET Piece Soccer Academy Limited | Education | 2024 |
| Setfords Group Limited | Financial services | 2020 |
| Setfords Interco Limited | Financial services | 2020 |
| Setfords Law Ltd | Information & communication | 2015 |
| Setfords Management Services Limited | Professional & scientific | 2020 |
| Setfords Midco Limited | Financial services | 2020 |
| Setfords Technology Solutions Ltd | Information & communication | 2025 |
| Setlist 1547 Limited | Hospitality | 2024 |
| Setpoint Networks Limited | Other services | 2006 |
| Seven Corners Press Limited | Professional & scientific | 1956 |
| Seven Farm Animal Feeds Limited | Wholesale & retail | 2018 |
| Seven Forty SIX Ltd | Information & communication | 2018 |
| Seven Seas Motors Limited | Wholesale & retail | 2016 |
| Sevengrams UK Limited | Wholesale & retail | 2017 |
| Seveni 7 Limited | Hospitality | 2018 |
| Sevilla Management Ltd | Professional & scientific | 2026 |
| Seymour & Partners Limited | Manufacturing | 1994 |
| Seymours Estate Agents (Leatherhead) Limited | Real estate | 2017 |
| Seymours Estate Agents (Ripley) Limited | Real estate | 2017 |
| SFR Studios Ltd | Arts & recreation | 2023 |
| SFU Ltd | Real estate | 2024 |
| SG Surrey Ltd | Real estate | 2026 |
| SGB Prestige Ltd | Wholesale & retail | 2010 |
| Shackleford Financial Consulting Ltd | Professional & scientific | 2020 |
| Shaco 97 Ltd | Transport & logistics | 2024 |
| Shadowbriar Solutions Limited | Information & communication | 2015 |
| Shaf Control Ltd | Real estate | 2019 |
| Shalford Auto Centre Ltd | Wholesale & retail | 2024 |
| Shalford Barbers Limited | Other services | 2023 |
| Shalford Lawn Tennis Club Limited | Arts & recreation | 2021 |
| Shalford MC Ltd | Households | 2020 |
| Shamley Green Property Limited | Construction | 2014 |
| Shammah Healthcare Limited | Health & social care | 2021 |
| Shamrock Logistical Services Limited | Information & communication | 2019 |
| Shanson Limited | Professional & scientific | 2005 |
| Sharkcoal Limited | Other services | 2025 |
| Sharp Line LZ Limited | Other services | 2022 |
| Sharp Shots Photo Club Ltd | Professional & scientific | 2016 |
| Sharp Shots Photo Club Online Ltd | Education | 2018 |
| Shaw Solutions Ltd | Professional & scientific | 2018 |
| Shawfields Limited | Households | 2007 |
| Shedfest Limited | Extraterritorial | 2020 |
| Sheermagic Capital LLP | | 2013 |
| Sheermagic Properties Limited | Real estate | 2013 |
| Sheerwater Solar Ltd | Administrative & support | 2022 |
| Shell Shots Limited | Professional & scientific | 2008 |
| Shepperton Pubs Limited | Hospitality | 2014 |
| Shere H R Consulting Limited | Administrative & support | 2005 |
| Shere Kitchens Ltd | Manufacturing | 2017 |
| Shere Madness Ltd | Professional & scientific | 2019 |
| Shere Properties Ltd | Real estate | 2023 |
| Sherwood Investment Holdings Ltd | Wholesale & retail | 2020 |
| Shiftingedge International Limited | Information & communication | 2016 |
| Shiftx Limited | Real estate | 2025 |
| Shilton Barlow Limited | Professional & scientific | 2009 |
| Shimmings Investment Company Limited | Households | 1971 |
| Shin Kick Limited | Arts & recreation | 2012 |
| Shin Kick Promotions Ltd | Arts & recreation | 2021 |
| Shinyok Sunpor Furniture Ltd | Wholesale & retail | 2024 |
| Shlomo Shmuley and Co Limited | Information & communication | 2020 |
| Shoreline Care Group Ltd | Health & social care | 2021 |
| Shot Goblin Studio Ltd | Information & communication | 2026 |
| Shrike Technologies Limited | Information & communication | 2009 |
| Shrimplin Planning & Development Ltd | Professional & scientific | 2019 |
| Shubh Tranport Ltd | Transport & logistics | 2025 |
| Shum Courier Ltd | Transport & logistics | 2025 |
| SIA Investments Ltd | Real estate | 2016 |
| Siba (Guildford) Ltd | Extraterritorial | 2019 |
| Sibmis Ltd | Real estate | 2021 |
| Sico Supply Ltd | Wholesale & retail | 2019 |
| Sidan Property Limited | Construction | 2023 |
| Sidecar Ventures Ltd | Professional & scientific | 2017 |
| Sidekick Productions Ltd | Information & communication | 2025 |