| Stealth Transport Logistics Ltd | Wholesale & retail | 2025 |
| Steamon Ironing Ltd | Other services | 2023 |
| Steeco Lifts Limited | Professional & scientific | 2012 |
| Steele & COE Ltd | Financial services | 2025 |
| Steer Development (Oxford) Ltd | Other services | 2011 |
| Stellar Build Group Ltd | Construction | 2024 |
| Stellar Designs Studio Ltd | Information & communication | 2024 |
| Stellar Property Holdings Ltd | Real estate | 2024 |
| Stem Group Ltd | Information & communication | 2015 |
| Stem Technologies Limited | Administrative & support | 2018 |
| Stenley Projects Ltd | Extraterritorial | 2020 |
| Steph Kiely Ltd | Professional & scientific | 2022 |
| Stephan Mouton Designs Ltd | Professional & scientific | 2016 |
| Stephanie Hicks Ltd | Health & social care | 2021 |
| Stephen Bailey-Kennedy Property Consultants Limited | Professional & scientific | 2015 |
| Stephen Good Limited | Other services | 2003 |
| Stephen Russell Construction Limited | Construction | 1976 |
| Stephen Russell Contracting Limited | Professional & scientific | 1987 |
| Stephens Scaffolding Ltd | Construction | 2025 |
| Steppenwolf Capital UK Ltd | Information & communication | 2016 |
| Stepping Stones Letting Ltd | Real estate | 2009 |
| Steve Ashman Consulting Ltd | Financial services | 2017 |
| Steve Warner SFX Limited | Information & communication | 2015 |
| STG 74 Ltd | Transport & logistics | 2026 |
| STH Enterprises Limited | Information & communication | 2026 |
| Stick on US Ltd | Professional & scientific | 2023 |
| Stillwell Rentals Limited | Real estate | 2020 |
| Stimulating Business Ltd | Professional & scientific | 1997 |
| Stiona Software Limited | Information & communication | 1997 |
| Stirling Corporation Limited | Wholesale & retail | 2009 |
| Stirling Lily Ltd | Other services | 2026 |
| Stirling Partners Finance Limited | Financial services | 2004 |
| Stock-Well Enterprises Ltd | Agriculture & fishing | 2022 |
| Stockwell Barns Limited | Administrative & support | 2000 |
| Stoke Farms Limited | Agriculture & fishing | 1960 |
| Stoke Mandeville Animal Products Limited | Real estate | 1936 |
| Stone and Fairford Leys Childcare Ltd | Health & social care | 2022 |
| Stone Reflections Ltd | Construction | 2012 |
| Stonecap Limited | Professional & scientific | 2019 |
| Stonechat Properties Ltd | Real estate | 2022 |
| Stonecroft Road Management Limited | Households | 1976 |
| Stonemill Park Management Company Limited | Households | 2021 |
| Stonewood Home Improvements Ltd | Construction | 2014 |
| Stoney Furlong Management Company Ltd | Real estate | 2015 |
| Stop 2 Shop Ltd | Wholesale & retail | 2024 |
| Stop Watch Pictures Ltd | Professional & scientific | 2019 |
| Storm Consultancy Services Limited | Information & communication | 1994 |
| Storm Jago Limited | Real estate | 2023 |
| Storm Warning Entertainment Limited | Other services | 2005 |
| Storsystem Limited | Wholesale & retail | 1992 |
| Story Shop Productions Limited | Information & communication | 1999 |
| STP Plumbing & Heating Ltd | Construction | 2023 |
| STR Restohaus Ltd | Wholesale & retail | 2025 |
| Stranks Holdings Limited | Real estate | 2019 |
| Stranks Investments Limited | Real estate | 2017 |
| Strat FX Ltd | Professional & scientific | 2024 |
| Strataguard Ltd | Manufacturing | 2026 |
| Stratasys UK Distribution Limited | Wholesale & retail | 2023 |
| Strategic Advisory Services Limited | Professional & scientific | 2005 |
| Strategic Digital Solutions Limited | Information & communication | 2017 |
| Strategic Petroleum Insights Ltd | Financial services | 2023 |
| Strategic Reporting Solutions Ltd | Information & communication | 2012 |
| Strategy Tribe Ltd | Information & communication | 2017 |
| Strathray Services Limited | Health & social care | 2015 |
| Stratos Lighting Ltd | Construction | 2022 |
| Strawberry Medical Limited | Health & social care | 2006 |
| Stream Comms Limited | Information & communication | 2009 |
| Streames Product Distribution (SPD UK) Ltd | Manufacturing | 2021 |
| Street 2 Pro Limited | Arts & recreation | 2024 |
| Streetplan Limited | Real estate | 1993 |
| Striped Equidae Properties Ltd | Real estate | 2020 |
| Strive IA Ltd | Education | 2024 |
| Strobima Ltd | Information & communication | 2026 |
| Stronger 1 Limited | Wholesale & retail | 2024 |
| Structured Solutions Limited | Agriculture & fishing | 2018 |
| Stuart Chapman Project Management Limited | Construction | 2014 |
| Stuart Fletcher Consulting Limited | Professional & scientific | 2025 |
| Stuart Leach Limited | Other services | 2010 |
| Stuart Paul Decorating Ltd | Construction | 2013 |
| Stuart Townsend Ltd | Professional & scientific | 2012 |
| Studio 105 Limited | Information & communication | 2025 |
| Studio Redrobin Ltd | Arts & recreation | 2017 |
| Studio Services UK Ltd | Manufacturing | 2024 |
| Stunintel Limited | Information & communication | 2025 |
| Styles Court Management Limited | Hospitality | 1996 |
| Stylish Beauty Clinic Limited | Other services | 2022 |
| Suadba Global Services Ltd | Manufacturing | 2021 |
| Suave Foods Ltd | Administrative & support | 2017 |
| Subadra Asset Management Limited | Administrative & support | 2019 |
| Subseat Ltd | Information & communication | 2026 |
| Success Cntrl Ltd | Information & communication | 2020 |
| Success Scaled Limited | Professional & scientific | 2025 |
| Successful Projects Limited | Professional & scientific | 2019 |
| SUE Balnaves Case Management Ltd | Health & social care | 2018 |
| Sugama Limited | Real estate | 2021 |
| Suitecloud ERP Consultants Ltd | Information & communication | 2019 |
| Sulecom Ltd | Wholesale & retail | 2024 |
| Sulis (International) Limited | Manufacturing | 2004 |
| Sulis Ltd | Manufacturing | 1994 |
| Sultania Aromas Ltd | Manufacturing | 2024 |