| 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 |
| Strut Direct LtdWednesbury, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2000 |
| Suez Advanced Solutions UK LimitedMaidenhead, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2006 |
| Summerhall Distillery LimitedEdinburgh, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2013 |
| Sunbeam Photographic LtdLondon, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2010 |
| Sunland Caribbean LtdLondon, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2008 |
| Suravii UK LimitedUnited Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2020 |
| Suretech Adhesive Tapes LtdDaventry, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 1998 |
| Suscom Industries LtdPemberton Wigan, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2004 |
| Swallow LimitedBirmingham, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 1995 |
| Swan London LimitedLondon, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2015 |
| Swara Trading International LimitedUnited Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2007 |
| Swift-Cut Automation LtdBurton-on-Trent, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2011 |
| Swissport Group UK LimitedRuncorn, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 1967 |
| Symington's LimitedLeeds, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 1990 |
| Synergy Wines LimitedDoncaster, United Kingdom · UKsynergywines.co.uk · checked 28 Oct 2026 | UK | 1 | – | – | – | – | 2020 |
| Sysco Gb LimitedAshford, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 1986 |
| T Warriors Brewery UK LtdThames Ditton, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2017 |
| Tabure LimitedBirkenhead, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2014 |
| Tamsel LtdLondon, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2008 |
| Tdr Capital LLPLondon, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2002 |
| Teddington Stores LimitedTeddington, United Kingdom · UKchecked 28 Oct 2026 | UK | 1 | – | – | – | – | 2014 |
| Tenuta Il Finale LtdWells, United Kingdom · UKtenutailfinale.com · checked 28 Oct 2026 | UK | 1 | – | – | – | – | 2019 |