| Sapphire Property Development Limited | Real estate | 2024 |
| Sapphire Sales Consultancy Ltd | Manufacturing | 2015 |
| Saqlain & Sons Limited | Professional & scientific | 2025 |
| Saracen Fire Protection Limited | Administrative & support | 2016 |
| Saraf Corporation Limited | Financial services | 2026 |
| Sarah’S Feline Friends Ltd | Agriculture & fishing | 2025 |
| Sardon International Limited | Manufacturing | 1979 |
| Sarthalmaa Limited | Health & social care | 2019 |
| Saspro Enterprises Limited | Construction | 2003 |
| Satkhira Ltd | Professional & scientific | 2025 |
| Saturday School Success Ltd | Education | 2014 |
| Savani Properties LLP | | 2012 |
| Savannah’S Skin Care Ltd | Other services | 2022 |
| Savant Housing Group Ltd | Real estate | 2025 |
| Savant Jewellers Limited | Wholesale & retail | 2025 |
| Savcor Ltd | Professional & scientific | 2025 |
| Savery's of Broadway (Ludlow) Limited | Professional & scientific | 2024 |
| Savery's of Broadway Limited | Wholesale & retail | 2011 |
| Savi Homes Ltd | Real estate | 2020 |
| Saviuc Limited | Construction | 2020 |
| Savoir-Faire Bilingual Ltd | Professional & scientific | 2023 |
| Savs Midlands Ltd | Wholesale & retail | 2025 |
| Sawyers Retail Limited | Wholesale & retail | 2018 |
| Saxon Digital Marketing Limited | Professional & scientific | 2020 |
| Saxon Holmes Surveyors Limited | Administrative & support | 2012 |
| Saxonminster Limited | Information & communication | 1994 |
| Saxton Digital Ltd | Professional & scientific | 2025 |
| SB Solutions Limited | Professional & scientific | 2024 |
| SB Strategic Advisory Services Ltd | Professional & scientific | 2022 |
| SBA Consultancy Limited | Information & communication | 2013 |
| Sboc MGT Co Ltd | Professional & scientific | 2023 |
| SBR Property Investments Ltd | Real estate | 2021 |
| SBZ Topco Limited | Financial services | 2024 |
| SC Hart Property Ltd | Real estate | 2021 |
| Scac Investments Ltd | Real estate | 2025 |
| Scancan Technologies Limited | Administrative & support | 2014 |
| SCE Trading Co Ltd | Hospitality | 2004 |
| SCH Trade Logistics Limited | Transport & logistics | 2026 |
| SCH Trading Ltd | Wholesale & retail | 2024 |
| Schnell Logistics Ltd | Transport & logistics | 2024 |
| Scholars Guidepost Limited | Education | 2024 |
| School Advice and Support Services Limited | Education | 2023 |
| School Business Advisory Ltd | Education | 2026 |
| School Gym Floors Limited | Construction | 2022 |
| SCI PRE Arrangement Limited | Extraterritorial | 1996 |
| Science Capital | Other services | 2010 |
| Scientific Human Insights Ltd | Professional & scientific | 2023 |
| SCL Construction & Management Ltd | Construction | 2023 |
| Scooby's Grooming Salon Ltd | Other services | 2022 |
| Scorpio FRA Limited | Professional & scientific | 2025 |
| Scott Sport Limited | Wholesale & retail | 2018 |
| Scriven Electrical Contractors Limited | Wholesale & retail | 1989 |
| Scyim Limited | Real estate | 2016 |
| SD Liquid Screed Ltd | Administrative & support | 2021 |
| SDA Digital Ltd | Information & communication | 2024 |
| SDM Engineering Limited | Professional & scientific | 2025 |
| Sdphysiotherapy (UK) Ltd | Other services | 2024 |
| SE7EN Architecture + Design Ltd | Professional & scientific | 2018 |
| Seafish Properties Limited | Real estate | 2010 |
| Seafish Restaurant 2 Limited | Hospitality | 2015 |
| Seafish Restaurant Limited | Hospitality | 2014 |
| Seaford Funeral Service Limited | Extraterritorial | 1967 |
| Sean Reilly Developments Limited | Construction | 2003 |
| Sean Reilly Limited | Construction | 1993 |
| Search International Ltd | Administrative & support | 2005 |
| Search UK Limited | Administrative & support | 2000 |
| Searchlight Private Limited | Professional & scientific | 2020 |
| Seated Furniture Limited | Wholesale & retail | 2008 |
| Seco Trans Limited | Transport & logistics | 2019 |
| Second Chance Jewellery Limited | Wholesale & retail | 2016 |
| Second City Bulldogs Ltd | Agriculture & fishing | 2023 |
| Second City Finance Ltd | Wholesale & retail | 2025 |
| Secure Car Parks Limited | Real estate | 1995 |
| Secure IT Bollards Ltd | Administrative & support | 2022 |
| Secure Locums Limited | Health & social care | 2008 |
| Secure Mind Solutions Limited | Other services | 2014 |
| Secure Payment Gateway Limited | Information & communication | 2023 |
| Secure Property Developments Limited | Real estate | 2011 |
| Secure Storage & Distribution Ltd | Real estate | 1999 |
| Secure Subs Limited | Hospitality | 2013 |
| Secureflame Ltd | Administrative & support | 2026 |
| Security Solutions GW Ltd | Manufacturing | 2015 |
| Seddons of Southport Limited | Extraterritorial | 1982 |
| Seeds for Change Ltd | Health & social care | 2025 |
| Seesaws Day Nurseries Limited | Education | 1993 |
| Seesaws Limited | Education | 1993 |
| Seesaws Training Limited | Education | 2017 |
| Sehmbi Enterprise Ltd | Real estate | 2020 |
| Sekhon & Co Properties Ltd | Real estate | 2016 |
| Sekhon & Co Property Investments Ltd | Real estate | 2022 |
| Sekhon Medical Limited | Health & social care | 2016 |
| SEL Medicare Limited | Health & social care | 2020 |
| Selah Assembly Ltd | Wholesale & retail | 2026 |
| Select Garages Ltd | Wholesale & retail | 2023 |
| Select Profiles Limited | Administrative & support | 1994 |
| Select Property Limited | Real estate | 2017 |
| Select Right Accounting Limited | Professional & scientific | 2023 |
| Select System Solutions Limited | Information & communication | 2018 |
| Selecta Systeme Ltd | Real estate | 2018 |
| Selecta Systems Limited | Wholesale & retail | 1982 |