| Sheldon Clayton Holdings LtdWest Bromwich, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2009 |
| Shenton Global LimitedAndover, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2016 |
| Shops For All LimitedLondon, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2017 |
| Shota LimitedLondon, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2018 |
| Shwen Shwen LimitedFaversham, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2020 |
| Sibbald LimitedBlackridge, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 1997 |
| Sicor International LimitedPlynouth, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 1993 |
| Signatory Vintage Scotch Whisky Co LtdPerth & Kinross, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 1988 |
| Signature Flatbreads LtdDunstable, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2014 |
| Signature Flight Support London Luton LimitedLuton, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 1988 |
| Sikelaia Wine LimitedLondon, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2021 |
| Silverlands Consulting LimitedRamsden Bellhouse, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2020 |
| Silverstone Circuits LimitedNorthamptonshire, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 1966 |
| Silvertrees 2024 LtdLondon, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2005 |
| Simarco International LtdWitham, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 1997 |
| Simply Conference & Corporate Eventsupport LimitedLondon, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2002 |
| Simpson Thacher & Bartlett LLPNew York, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2023 |
| Sippa Club LimitedLondon, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2023 |
| Skylogistix GMBHNeu-Isenburg, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2010 |
| Slater MenswearUnited Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 1973 |
| Slc Turnberry LtdUnited Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 1997 |
| Smart Directions LimitedLuton, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2003 |
| Sme London LtdLondon, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2010 |
| Smooth Red LtdThames Ditton, United Kingdom · UKsmoothred.com · checked 28 Oct 2026 | UK | 1 | – | – | – | – | 2004 |
| Snack Food Restaurant LimitedUnited Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 1989 |
| Snowdonia Cheese Company LimitedRhyl, United Kingdom · UKsnowdoniacheese.co.uk · checked 28 Oct 2026 | UK | 1 | – | – | – | – | 2001 |
| Soco System LimitedStoke on Trent, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 1990 |
| Soho House UK LtdLondon, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 1993 |
| Soil and Vine LimitedLondon, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2023 |
| Sopers House LLPCuffley, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2023 |
| Source Developments LtdEdinburgh, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2010 |
| Sourcing International LimitedWigston, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2020 |
| South Heat & Electrical LtdWimborne, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2009 |
| Specialised Polymer Engineering LtdSouthampton, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2001 |
| Splendid Import and Export LtdLondon, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2018 |
| Squire Patton Boggs LLPLondon, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2008 |
| St Giles Hotel LtdFeltham, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 1999 |
| Standon Hall Events LimitedStafford, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2019 |
| Stanley Dock Hotel LimitedBorehamwood, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2012 |
| Star Divine Investments LtdLondon, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2017 |
| Stardom LimitedBrierley Hill, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 1993 |
| Starling Contracting LtdLondon, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2006 |
| Station 57 LtdNorthwood Hills, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2015 |
| Staycold Export LtdFlintshire, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 1996 |
| Stellar Lighting Ltd.London, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2014 |
| Stephens and George Magazines LimitedMerthyr Tydfil, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 1994 |
| Stepper LtdTonbridge, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 1990 |
| Stonex Financial LtdLondon, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2005 |
| Stornoway Shipping Services LtdIsle of Lewis, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 1994 |
| Strictly Theatre Co LimitedNorfolk, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2017 |