| Salon Software Solutions Limited | Information & communication | 2014 |
| Saltdean Lido (Brighton) Limited | Arts & recreation | 1997 |
| Sanu VAL Tech Limited | Professional & scientific | 2014 |
| Sarah Chesser Limited | Administrative & support | 2007 |
| SBA Bureau Services Limited | Professional & scientific | 1994 |
| Scampion Investments Limited | Financial services | 2005 |
| Scarlet Computing Limited | Information & communication | 2000 |
| Scott and Young Associates Limited | Administrative & support | 1989 |
| Seal Consulting International Ltd | Administrative & support | 2003 |
| Second Grimsbury Green Amenity Company Limited | Real estate | 1993 |
| Sefa Barber Ltd | Other services | 2023 |
| Sevans Services Ltd | Other services | 2025 |
| Seventeen Victoria Square Clifton Management Company Limited | Extraterritorial | 1999 |
| Severn Trent Green Power (Ardley) Limited | Water & waste | 2006 |
| SFP Automation Limited | Water & waste | 1989 |
| Shiplake Court Enterprises Limited | Hospitality | 1976 |
| Shun Chang Limited | Manufacturing | 2006 |
| Siege Ltd | Hospitality | 2024 |
| Silver Bullet Airstreams Limited | Hospitality | 2014 |
| Silver Stream Recruitment Limited | Professional & scientific | 2002 |
| Simon Ross Associates Limited | Professional & scientific | 2007 |
| Simplicity Payroll Services Limited | Professional & scientific | 2005 |
| Simpson Associates Consulting Ltd | Construction | 2011 |
| Sinead Williamson Limited | Wholesale & retail | 2025 |
| Sinnels Field Management Company Limited | Households | 1977 |
| Sitting Pretty by Pride Mobility Limited | Manufacturing | 2021 |
| SJA UK Limited | Professional & scientific | 2005 |
| Skirmett Supplies Limited | Professional & scientific | 2006 |
| Skirrid Toys Limited | Extraterritorial | 2003 |
| Slowly Sideways | Arts & recreation | 2007 |
| Smart Photography Limited | Professional & scientific | 2005 |
| Smarter Quality Ltd | Professional & scientific | 2025 |
| Smith's Construction (Bletchington) Limited | Construction | 1979 |
| Snouting About Limited | Other services | 2005 |
| Sobo Holdings Limited | Financial services | 2016 |
| Sofie Enterprises | Administrative & support | 2015 |
| Solutions in Accounting Ltd | Professional & scientific | 2004 |
| Sonoco Metal Packaging Aerosols UK Limited | Manufacturing | 1935 |
| Sonoco Metal Packaging Group UK Limited | Professional & scientific | 2020 |
| Sonoco Metal Packaging Holdings UK Limited | Professional & scientific | 2020 |
| Sonoco Metal Packaging UK Limited | Manufacturing | 2021 |
| Sonoco Promotional Metal Packaging UK Limited | Manufacturing | 1989 |
| Sophos Nominees Limited | Administrative & support | 2003 |
| Sosmyworld Limited | Wholesale & retail | 2007 |
| South Moreton Boxing Club Ltd | Arts & recreation | 2006 |
| Span Network Solutions Limited | Information & communication | 1998 |
| Sparkling Skills Academy Limited | Education | 2025 |
| Spartacus Associates Limited | Extraterritorial | 1999 |
| Spatial Alignment Limited | Professional & scientific | 2008 |
| Spicecrest Limited | Hospitality | 1998 |
| Spirit Bar Limited | Hospitality | 1999 |
| Sportyminis Limited | Education | 2017 |
| Springfield Road Residents Company Limited | Households | 1998 |
| Springwood Electrical Limited | Construction | 2022 |
| ST. Andrew's Residential Care Home Limited | Health & social care | 1988 |
| ST. Ethelwold Trading Ltd | Hospitality | 2006 |
| ST. Mary's (PCC) Limited | Wholesale & retail | 1996 |
| Stamp Travel Limited | Other services | 2022 |
| Stanford Property Holdings Limited | Administrative & support | 1994 |
| Star Capital Holdings Limited | Financial services | 2026 |
| Starensier UK Limited | Wholesale & retail | 2021 |
| Starline Central (UK) Limited | Construction | 2024 |
| Stationfields Limited | Real estate | 1999 |
| Staverton Grange Management Company Limited | Households | 1995 |
| Steelshade Trade Limited | Wholesale & retail | 2026 |
| Steventon Flat Roofing Limited | Construction | 2025 |
| Stewart Wells Interim Management Limited | Professional & scientific | 2020 |
| Stocks Plumbing & Heating LLP | | 2002 |
| Stonelane Properties Limited | Real estate | 1999 |
| Stonor Enterprises Partner Limited | Financial services | 2025 |
| Stow Opticians Limited | Wholesale & retail | 2016 |
| Strategy MAX Limited | Professional & scientific | 2023 |
| Strawberry Hills Studios Limited | Arts & recreation | 2003 |
| Stuart Turner Limited | Manufacturing | 1906 |
| Studio 7A Limited | Information & communication | 2001 |
| Studio BEN Allen Limited | Professional & scientific | 2013 |
| Studio Kloof Ltd | Construction | 2022 |
| Success Gurus Limited | Professional & scientific | 2003 |
| Summers, Davis & SON Limited | Extraterritorial | 1950 |
| Sunningwell Command Control Limited | Wholesale & retail | 1998 |
| Sunview Developments Limited | Construction | 2011 |
| Superior Construction (UK) Limited | Construction | 1993 |
| Supportcomm.Co.Uk Limited | Manufacturing | 2005 |
| Sure Line Leisure Services | | 1999 |
| Swift Engraving Services Limited | Manufacturing | 2009 |
| Swift Labels Limited | Extraterritorial | 2009 |
| Swift Safety Ltd | Extraterritorial | 2013 |
| Swindell Painting Limited | Manufacturing | 1983 |
| Sybus Consultancy Limited | Professional & scientific | 1999 |
| Synaptikos Consulting Limited | Professional & scientific | 2025 |
| Systems and Solutions (Sales) Limited | Information & communication | 1995 |
| T H J Limited | Hospitality | 2003 |
| T M R Automotive Limited | Wholesale & retail | 2004 |
| T. J. Prew Cars Limited | Wholesale & retail | 2005 |
| Tabcom Limited | Manufacturing | 1999 |
| Tackle Marketing Limited | Other services | 1993 |
| Tactical Training and Consultancy to Inspire Change Actions Limited | Professional & scientific | 2003 |
| Tariq Khuja Limited | Hospitality | 2006 |
| Taylor Whalley & Spyra Limited | Construction | 1996 |
| Tdeltas Limited | Professional & scientific | 2005 |