| Stone PEG Limited | Wholesale & retail | 2004 |
| Stone Zone & Landscaping Centre Ltd | Extraterritorial | 2020 |
| Stonebarrow Limited | Construction | 2017 |
| Stonebarrow Property Limited | Real estate | 2023 |
| Stoneleigh Two Limited | Financial services | 2022 |
| Stoneriver (Milford) Ltd | Construction | 2025 |
| Stoneriver Homes Ltd | Construction | 2017 |
| Stoneriver Projects Ltd | Construction | 2015 |
| Stones UK Ltd. | Extraterritorial | 2008 |
| Stonesetuk Ltd | Construction | 2019 |
| Stonespiral Limited | Information & communication | 2006 |
| Storofile Limited | Administrative & support | 1991 |
| Stour & Avon Properties Ltd | Real estate | 2022 |
| Stour View Electrical Limited | Construction | 2016 |
| Stourbridge Limited | Administrative & support | 2005 |
| Stourview Joinery Ltd | Manufacturing | 2023 |
| Strada Development Management Limited | Professional & scientific | 2025 |
| Straight Eight Engineering Limited | Manufacturing | 2016 |
| Strakt Limited | Professional & scientific | 2024 |
| Strategic Solutions Regulatory Services Limited | Professional & scientific | 2025 |
| Strato Technology Ltd | Information & communication | 2023 |
| Stratton House (Dorset) Management Company Limited | Households | 2016 |
| Strawberry Books Ltd | Wholesale & retail | 2022 |
| Streak Free Window Cleaning Dorset Ltd | Administrative & support | 2024 |
| Streamline Consultancy Group Ltd | Information & communication | 2023 |
| Streamline Innovations Limited | Professional & scientific | 2023 |
| Streamsure Solutions Limited | Information & communication | 2010 |
| Strebor Fire Protection (International) Limited | Manufacturing | 2009 |
| Streetscene Addiction Recovery | Health & social care | 2006 |
| Striped Logic Limited | Professional & scientific | 2026 |
| Striq Ltd | Education | 2026 |
| Strivetechai Limited | Information & communication | 2014 |
| Strong Agile PPM Ltd | Professional & scientific | 2023 |
| Strongevity Ltd | Education | 2025 |
| Stronghold Ventures Ltd | Hospitality | 2025 |
| Strongtype Limited | Information & communication | 2018 |
| Stuart Lodge Management Limited | Households | 2004 |
| Stuart Randall Construction Limited | Construction | 2019 |
| Stuart W Brown Ltd | Information & communication | 2018 |
| Stuccigus Ltd | Arts & recreation | 2024 |
| Studio 145 Ltd | Professional & scientific | 2022 |
| Studio 3 Hair Limited | Other services | 2015 |
| Studio 5 Games Limited | Information & communication | 2022 |
| Studio Bank Limited | Professional & scientific | 2019 |
| Studio Benzaquen Ltd | Hospitality | 2025 |
| Studio Kick Ltd | Professional & scientific | 2021 |
| Studio One (Dorsets Centre for Performing Arts) Limited | Arts & recreation | 2015 |
| Studiofortythree Limited | Professional & scientific | 2024 |
| STUDIOX7 Ltd | Extraterritorial | 2010 |
| Sturgess Financial Solutions Ltd | Financial services | 2025 |
| Sturminster GC Holdings Limited | Arts & recreation | 2021 |
| Sturminster Marshall Golf Club Limited | Arts & recreation | 2006 |
| Sturminster Marshall Golf Shop Ltd | Wholesale & retail | 2024 |
| Style Servicing Ltd | Construction | 2017 |
| Subsea Industries Limited | Professional & scientific | 2026 |
| Subsurface Journal Limited | Wholesale & retail | 2020 |
| Subsurface Magazine Ltd | Information & communication | 2026 |
| Succeed and Grow Ltd | Professional & scientific | 2023 |
| Sudoblark Limited | Information & communication | 2023 |
| SUGAR4BONGO Ltd | Information & communication | 2023 |
| Suite Living Limited | Real estate | 2017 |
| SUK Events Limited | Hospitality | 2023 |
| Sullivan Artifice and Technical Solutions Limited | Professional & scientific | 2021 |
| Sullivan Business Services Ltd | Professional & scientific | 2017 |
| Summerbrook Consulting Ltd | Professional & scientific | 2011 |
| Summerland Engineering Limited | Professional & scientific | 2014 |
| Summit Alternative Education Ltd | Education | 2026 |
| Summit Cleaning Limited | Administrative & support | 2023 |
| Summit Commercial Consulting Ltd | Professional & scientific | 2023 |
| Summit Infrastructure Consultants Ltd | Professional & scientific | 2024 |
| Sumner & Sumner Holdings Ltd | Information & communication | 2022 |
| Sun Golf SKI Limited | Real estate | 2017 |
| Sunflower Virtual Assistant Limited | Administrative & support | 2024 |
| Sunridge Shades Limited | Households | 1995 |
| Sunset Advisory Limited | Professional & scientific | 2025 |
| Sunshine 13 Limited | Financial services | 2019 |
| Sunshine Windows & Conservatories (Dorset) Ltd | Construction | 2014 |
| Sunstone Commercial Properties Ltd | Real estate | 2005 |
| Sunstone Energy Ltd | Construction | 2009 |
| Supana Limited | Professional & scientific | 2001 |
| Super Engineer Limited | Mining & quarrying | 2011 |
| Superbee Consulting Ltd | Professional & scientific | 2022 |
| Superfast Productions Ltd | Information & communication | 2017 |
| Superior Aerospace Limited | Extraterritorial | 2005 |
| Superior Automotive Limited | Extraterritorial | 2005 |
| Superior Direct Limited | Extraterritorial | 2009 |
| Superior Group Limited | Financial services | 2005 |
| Superior Limited | Extraterritorial | 2007 |
| Superior Link Limited | Extraterritorial | 1998 |
| Superior Medical Limited | Extraterritorial | 2005 |
| Superior Project Design Ltd | Construction | 2026 |
| Superior Sciences Limited | Extraterritorial | 2011 |
| Superior Sealing Solutions Limited | Extraterritorial | 2020 |
| Superior Sealing Technology Limited | Extraterritorial | 2011 |
| Superior Seals Limited | Manufacturing | 1966 |
| Superior Specials Limited | Manufacturing | 1989 |
| Superior Store Limited | Extraterritorial | 2009 |
| Superlast Limited | Extraterritorial | 2012 |
| Superyacht Connections Limited | Arts & recreation | 2021 |
| Supported Computing Limited | Information & communication | 2005 |