| Storm 90 PWR Limited | Professional & scientific | 2007 |
| Storm Construction and Plant Limited | Administrative & support | 2023 |
| Stormflood Studios CYF. | Information & communication | 2019 |
| Stormhold Hospitality Ltd | Hospitality | 2025 |
| Storytold Creative Ltd | Professional & scientific | 2025 |
| Stotesburys Limited | Hospitality | 2024 |
| Stove-Tec IW Ltd | Construction | 2003 |
| Stow Park Limited | Real estate | 2013 |
| Strand Energy & Engineering Ltd | Construction | 2014 |
| Strategic Investment, Management and Business Advice Limited | Professional & scientific | 2015 |
| Strategic Operations Limited | Administrative & support | 2006 |
| Strawberry Field Property Limited | Extraterritorial | 2019 |
| Strawberry Hill Collective Ltd | Real estate | 2024 |
| Streamline Prep Solutions Ltd | Administrative & support | 2025 |
| Street Automotive Ltd | Wholesale & retail | 2023 |
| Streetwave Ltd | Information & communication | 2021 |
| Stretched OUT Limited | Transport & logistics | 1999 |
| Stripes Lawn Care Limited | Administrative & support | 2018 |
| Strive Media Limited | Information & communication | 2016 |
| Strive Property Solutions Limited | Real estate | 2024 |
| Strokestown Ltd | Professional & scientific | 2009 |
| Structabuild Ltd | Construction | 2025 |
| Structor X Ltd | Construction | 2024 |
| Strykers Developments Ltd | Construction | 2018 |
| STS Commercial Limited | Information & communication | 2013 |
| Stuart LEE Smith Limited | Extraterritorial | 2025 |
| Stuart Morley Transport Limited | Other services | 2015 |
| Stuart Smith Plant Hire Limited | Manufacturing | 2002 |
| Stuart Walker Property Ltd. | Construction | 2020 |
| Students Plus Services Limited | Real estate | 2025 |
| Studio Cemento Ltd | Manufacturing | 2025 |
| Studio Gallagher Ltd | Manufacturing | 2022 |
| Studio Hovey Limited | Information & communication | 2016 |
| Studio IV Ltd | Other services | 2026 |
| Stunning SA Ltd | Hospitality | 2017 |
| Styled-By-Vee Limited | Wholesale & retail | 2025 |
| SU7 Limited | Arts & recreation | 2017 |
| Sub-Terra Works (Plant) Limited | Construction | 2020 |
| Sub-Terra Works Limited | Construction | 2020 |
| Subh Properties Limited | Real estate | 2022 |
| Subh Ventures Limited | Real estate | 2020 |
| Submarine Music Ltd | Information & communication | 2014 |
| Subo&Sons Ltd | Wholesale & retail | 2022 |
| Sudanese Women of Peace (Swop) Ltd | Health & social care | 2025 |
| SUE Ensaff Limited | Real estate | 2010 |
| Sugar Beard Limited | Wholesale & retail | 2018 |
| Sugarjobs Limited | Administrative & support | 2009 |
| Suhayl Select Limited | Professional & scientific | 2025 |
| Suite Dreams Furnishing Centre (South Wales) Limited | Wholesale & retail | 1997 |
| Sully TM Ltd | Construction | 2025 |
| Sultan Solutions for YOU Ltd | Administrative & support | 2025 |
| Sultanpur Ltd | Hospitality | 2024 |
| Sumaia Gabir Limited | Health & social care | 2026 |
| Summer Gardens Design Ltd. | Administrative & support | 2018 |
| Summerhayes Garage Limited | Wholesale & retail | 2025 |
| Summerhill Close (IW) Management Limited | Households | 2007 |
| Summerlea Court (Isle of Wight) Management Company Limited | Households | 1991 |
| Summit Standards Limited | Education | 2012 |
| Sumrah Properties Limited | Real estate | 2019 |
| Sun Capture Systems Ltd | Construction | 2023 |
| Sunbim Foods Ltd | Wholesale & retail | 2019 |
| Sunbim Properties Ltd | Real estate | 2025 |
| Sunbrainch Ltd | Wholesale & retail | 2026 |
| Sunhealth Fitness & Performance Ltd | Arts & recreation | 2020 |
| Sunkissed Salon IOW Limited | Information & communication | 2023 |
| Sunkissed Solution Limited | Administrative & support | 2014 |
| Sunnah Gift Box Limited | Wholesale & retail | 2023 |
| Sunny Zdeny Limited | Information & communication | 2025 |
| Sunnybank Childrens Nursery (Chepstow) Limited | Education | 2003 |
| Sunnybank Farm & Holdings Ltd | Agriculture & fishing | 2022 |
| Sunnyway Partners Ltd | Professional & scientific | 2024 |
| Sunrise Dreams Ltd | Administrative & support | 2010 |
| Sunrise Residential Homes Limited | Real estate | 2024 |
| Sunrise Tech Consulting Limited | Professional & scientific | 2023 |
| Sunshade Interiors Limited | Manufacturing | 2013 |
| Supdog Ltd | Administrative & support | 2020 |
| Super Clean Valets Ltd | Wholesale & retail | 2025 |
| Super Direct Ltd | Hospitality | 2023 |
| Super Lucky Ltd | Health & social care | 2019 |
| Super Sparks Electrical Services Ltd | Construction | 2017 |
| Super Wash NPT Ltd | Wholesale & retail | 2024 |
| Supergrow Limited | Administrative & support | 2011 |
| Superior Vapour (Bath) Limited | Health & social care | 2015 |
| Superior Vapour (Bedminster) Limited | Wholesale & retail | 2013 |
| Superior Vapour (Blackwood) Limited | Administrative & support | 2013 |
| Superior Vapour (Broadmead) Limited | Wholesale & retail | 2014 |
| Superior Vapour (Cardiff) Limited | Administrative & support | 2013 |
| Superior Vapour (Pontypridd) Limited | Administrative & support | 2013 |
| Superior Vapour (Yate ) Limited | Wholesale & retail | 2020 |
| Superior Vapour Ltd | Wholesale & retail | 2016 |
| Superstar Music Limited | Arts & recreation | 1970 |
| Superstar Ventures Limited | Arts & recreation | 1970 |
| Superyacht Sales UK Ltd | Manufacturing | 2024 |
| Supply Core Limited | Wholesale & retail | 2025 |
| Support Nucleus Ltd | Transport & logistics | 2024 |
| Supreme Interiors Isle of Wight Limited | Construction | 2018 |
| Supun Roofing Limited | Construction | 2025 |
| Suraiya Limited | Hospitality | 2022 |
| Surefix Drywall Systems Ltd | Construction | 2018 |
| Surepass Newport Limited | Education | 2025 |