| S T L Roofing Services Limited | Construction | 2013 |
| S Wadey Roofing Limited | Construction | 2021 |
| S&A on the Move Ltd | Transport & logistics | 2017 |
| S&C Unique Wood Solutions Ltd | Construction | 2021 |
| S&P Cleaning Services Limited | Administrative & support | 2023 |
| S. Angus Limited | Professional & scientific | 2011 |
| S.A. Home Improvements (Southern) Limited | Construction | 2008 |
| S.A.D. PUB Ltd | Hospitality | 2014 |
| S.C.R Security Services Ltd | Administrative & support | 2024 |
| S.E.A Windows & Doors Limited | Construction | 2002 |
| S.E.A. (Manufacturing) Windows & Doors Limited | Construction | 2002 |
| S.K. & Popsy Limited | Professional & scientific | 2024 |
| S3 Advisory Ltd | Professional & scientific | 2024 |
| S5 Consulting Ltd | Professional & scientific | 2025 |
| Saasdesk Limited | Information & communication | 2010 |
| Sabre Plastic Mouldings Limited | Manufacturing | 2003 |
| Sabroe Limited | Professional & scientific | 1984 |
| Sacred Heart Chapel Ltd | Hospitality | 2021 |
| Safe and Solar Window Films Ltd | Construction | 2026 |
| Safe Chaos Limited | Administrative & support | 2025 |
| Safe Hands Consultancy (UK) Ltd | Professional & scientific | 2022 |
| Safe Hands Estates Ltd | Real estate | 2024 |
| Safe Hands Training & Development (UK) Ltd | Education | 2025 |
| Safe N Social Limited | Information & communication | 2022 |
| Safe Routes Solutions Ltd | Administrative & support | 2025 |
| Safeaid Limited | Manufacturing | 2013 |
| Safeaid Supplies LLP | | 2013 |
| Safechain Software Ltd | Information & communication | 2026 |
| Safeguard Fire Protection Ltd | Construction | 1999 |
| Saffron Mist Ltd | Hospitality | 2026 |
| Sage Analysis Limited | Information & communication | 2024 |
| Sage and Salt Studio Ltd | Wholesale & retail | 2023 |
| Sage Group Developments Limited | Construction | 2024 |
| Sage Group Holdings Limited | Financial services | 2024 |
| Sagesse International Ltd | Professional & scientific | 2015 |
| SAI KDA Limited | Extraterritorial | 2019 |
| SAI Veritas Limited | Professional & scientific | 2024 |
| Sail and Powerboats Ltd | Professional & scientific | 2024 |
| Sail Style Limited | Extraterritorial | 2016 |
| Sailrocket Ltd | Information & communication | 2004 |
| Saint Florent Ltd | Financial services | 2026 |
| Saka Pubs Limited | Hospitality | 2025 |
| Sakina Support Ltd | Health & social care | 2023 |
| Sakscentre Limited | Professional & scientific | 2019 |
| Sali Spice Ltd | Administrative & support | 2017 |
| Salisbury and Saville Limited | Construction | 2014 |
| Salisbury Estate Holdings Limited | Financial services | 2020 |
| Salisbury Investments Limited | Financial services | 2020 |
| Salisbury Stone Limited | Manufacturing | 2023 |
| Salix Motor Company Ltd | Wholesale & retail | 2021 |
| Sally Cat Limited | Information & communication | 2025 |
| Salmon Labs Ltd | Professional & scientific | 2023 |
| SALON21 - by Alexandra Ltd | Other services | 2022 |
| Salt & Clay Limited | Wholesale & retail | 2021 |
| Samaita PVT Limited | Extraterritorial | 2016 |
| Samcoh Development Ltd | Construction | 2024 |
| Same Day Dentistry Laboratories Limited | Health & social care | 2020 |
| Samford Projects Ltd | Professional & scientific | 2022 |
| Sammy's Cats , Nails & Teeth Ltd | Other services | 2025 |
| Sammy's Dog Grooming Limited | Other services | 2018 |
| Samsurk Systems Ltd | Wholesale & retail | 2025 |
| Samuel T Ltd | Wholesale & retail | 2026 |
| Samurai Skies Limited | Other services | 2015 |
| San-Nzo Ltd | Information & communication | 2020 |
| Sana Sortation Ltd | Transport & logistics | 2022 |
| Sanbar Group Ltd | Information & communication | 2022 |
| Sancus Tech Limited | Construction | 2023 |
| Sandridge House (Self Build) Ltd | Real estate | 2023 |
| Sandy Code Limited | Information & communication | 2019 |
| Sandyplace Limited | Wholesale & retail | 2005 |
| Sandys Medical Services Limited | Health & social care | 2019 |
| Saner Design Limited | Information & communication | 2012 |
| Sankey Limited | Real estate | 2019 |
| Santocha Supply Ltd | Professional & scientific | 2025 |
| Sapphire Blue Consulting Ltd | Professional & scientific | 2025 |
| Sapphire Financial Planning Ltd | Professional & scientific | 2016 |
| Sapphire Investment Properties Ltd | Real estate | 2019 |
| Sara Luxury Developments Ltd | Construction | 2024 |
| Sarah Kidd Limited | Health & social care | 2021 |
| Sarah Louise Interiors Limited | Manufacturing | 2011 |
| Sarah Muwanga Ltd | Arts & recreation | 2023 |
| SAS Property Investments Limited | Real estate | 2006 |
| Sass & Sass Sourcing Ltd | Professional & scientific | 2020 |
| Sass Sourcing Ltd | Professional & scientific | 2025 |
| Satellite Information Technology Ltd | Information & communication | 2024 |
| Saunders Consultancy Limited | Education | 2018 |
| Savage Pixel Studios Limited | Information & communication | 2019 |
| Sawyers Crescent Developments Ltd | Construction | 2020 |
| Saxon Consultants Limited | Information & communication | 2025 |
| SB Business Management Services Limited | Professional & scientific | 2018 |
| SB Dent Ltd | Health & social care | 2022 |
| SB Security Ltd | Administrative & support | 2010 |
| SB Security Services Ltd | Administrative & support | 2010 |
| SB Security Solutions Limited | Administrative & support | 2005 |
| SBA Solutions Limited | Administrative & support | 2003 |
| SBAB888 Ltd | Financial services | 2025 |
| Sbarcea Ltd | Construction | 2018 |
| SBF Properties Limited | Real estate | 2016 |
| SBO Enterprises Limited | Construction | 2013 |
| SBO Lettings Ltd | Real estate | 2025 |