| S Ferguson Engineering Ltd | Professional & scientific | 2025 |
| SA Barber Ltd | Other services | 2025 |
| Saltire Systems Ltd | Information & communication | 2026 |
| Sams Applied Marine Science Enterprise Limited | Professional & scientific | 2001 |
| Sams Limited | Professional & scientific | 2006 |
| Samudra Scotland Limited | Agriculture & fishing | 2025 |
| Sarah Nicholson Ltd | Health & social care | 2026 |
| SAS Auto Services (Scotland) Ltd | Wholesale & retail | 2026 |
| Satchel Scotland Ltd | Wholesale & retail | 2021 |
| Savary Timber Ltd | Manufacturing | 2026 |
| School's OUT Oban | Other services | 2005 |
| SCL Evolution Limited | Professional & scientific | 2025 |
| Scotnest Limited | Professional & scientific | 2017 |
| Scottish Marine Institute | Professional & scientific | 2011 |
| Scotwood Macdonald Holdings Limited | Financial services | 2024 |
| Scotwood Macdonald Limited | Agriculture & fishing | 2014 |
| SD Equity Group Limited | Real estate | 2024 |
| Sea Change Innovations Ltd | Agriculture & fishing | 2023 |
| Seafare Ltd | Wholesale & retail | 2021 |
| Seafari Adventures (Oban) Ltd | Administrative & support | 2012 |
| Seagrass Marine Limited | Transport & logistics | 2019 |
| Seagrass Solutions Limited | Professional & scientific | 2019 |
| Seator Groundworks Limited | Construction | 2025 |
| Seaview Ltd Co Limited | Real estate | 2024 |
| Seaweed Scotland | Other services | 2014 |
| Seaweed Services Ltd | Agriculture & fishing | 2023 |
| Seawork (Scotland) Limited | Construction | 1988 |
| Seeview Property Limited | Real estate | 2026 |
| Seil Biodiversity CIC | Agriculture & fishing | 2020 |
| Serenity Stays Oban Limited | Hospitality | 2026 |
| Sezanne Marine Limited | Professional & scientific | 2015 |
| Sharp Edge Projects (Scotland) Limited | Construction | 2021 |
| Shaw's Law Holding Ltd | Professional & scientific | 2024 |
| Shaw's Law Ltd | Real estate | 2013 |
| Shaw’S Law Trustees Limited | Professional & scientific | 2021 |
| Shiaba Ltd | Professional & scientific | 2010 |
| Shian Group Limited | Wholesale & retail | 2015 |
| Shian Property Limited | Real estate | 2016 |
| Shielbridge Energy Ltd | Administrative & support | 2012 |
| Shieling Holidays (Mull) Limited | Hospitality | 2017 |
| Shimah Limited | Hospitality | 2019 |
| Silver Sea Fish Limited | Agriculture & fishing | 2010 |
| Silver Sea Mussels Limited | Agriculture & fishing | 2010 |
| Silver Star Fishing Ltd | Agriculture & fishing | 2023 |
| Silver Stoat Productions Limited | Information & communication | 2024 |
| Simmonds Equipment Limited | Wholesale & retail | 2020 |
| Sinclair Plant Limited | Construction | 2021 |
| Sirs UK Holdings Limited | Financial services | 2026 |
| Skyoban Stores Limited | Wholesale & retail | 2023 |
| Sloan Wells Holdings Limited | Hospitality | 2019 |
| Slochd Limited | Hospitality | 2013 |
| Socair Centre Limited | Real estate | 2024 |
| Solar Property Group Ltd | Real estate | 2022 |
| Sonas Limited | Hospitality | 2003 |
| Sorcha Scotland Ltd | Manufacturing | 2015 |
| Soroba Community Enterprise Limited | Education | 2006 |
| Space (Oban) Ltd | Other services | 2023 |
| Special Publications Company Limited | Professional & scientific | 1997 |
| Spirit & Nature Ltd | Information & communication | 2019 |
| Spud Stop 26 Limited | Hospitality | 2026 |
| SSS Properties Oban Limited | Financial services | 2014 |
| ST Columba's Drimnin Trust Limited | Education | 2005 |
| ST Medical Aesthetics Limited | Health & social care | 2020 |
| Staffa Trips Iona Limited | Transport & logistics | 2019 |
| Steeman Engineering Ltd | Manufacturing | 2013 |
| Stepped Piston Engines Limited | Professional & scientific | 1982 |
| Strategic Technical Solutions Ltd | Public administration | 2024 |
| Strathdene Projects Limited | Construction | 2021 |
| Stravaigin Sailing Ltd | Administrative & support | 2024 |
| Stuart Ross (Scotland) Limited | Administrative & support | 2003 |
| Sunart Networks Limited | Information & communication | 2019 |
| T Barbour Limited | Wholesale & retail | 2007 |
| T.E.A. Time Krakow Ltd | Manufacturing | 2025 |
| Taic Comann Eachdraidh Lios MOR Limited | Arts & recreation | 2002 |
| Taranaki Ltd | Professional & scientific | 2026 |
| Tartan GIN Ltd | Extraterritorial | 2025 |
| Taste of Argyll Kitchen Ltd | Hospitality | 2020 |
| Taste of Argyll Ltd | Hospitality | 2019 |
| Taynuilt Inn Freehold Limited | Hospitality | 2019 |
| Tayvallich Community Company | Other services | 2008 |
| Technical Services and Agencies (International) Limited | Professional & scientific | 1957 |
| Tenement Productions Ltd | Information & communication | 2025 |
| THE Appin Centre Limited | Real estate | 2003 |
| THE Ardmore Farming Partnership | | 1997 |
| THE Argyllshire Advertiser, Limited | Professional & scientific | 1956 |
| THE Argyllshire Gathering Nominees | Other services | 2012 |
| THE Argyllshire Gathering Trust | Education | 2020 |
| THE Bakery Tobermory Limited | Wholesale & retail | 2018 |
| THE Bivvy Ltd | Hospitality | 2025 |
| THE Clan Macintyre Trust | Education | 2008 |
| THE Croft Collective Ltd | Hospitality | 2023 |
| THE Dalmally Community Company | Arts & recreation | 2002 |
| THE Dewcross Research Company Ltd. | Real estate | 1999 |
| THE Estates Office Limited | Real estate | 2018 |
| THE Falls of Lora Hotel Ltd | Hospitality | 2021 |
| THE Felt Company Scotland Ltd | Manufacturing | 2023 |
| THE Fishouse (Oban) Limited | Hospitality | 2015 |
| THE Happy WEE Gym Limited | Arts & recreation | 2022 |
| THE Harris Felt Company Ltd | Manufacturing | 2023 |
| THE Highland Bookkeeper Ltd | Professional & scientific | 2025 |