| Schrack Technik GmbH | Vienna |
| SchwarzerKater.at | Carinthia |
| Science Park Graz GmbH | |
| Sclable Business Solutions GmbH | |
| SCOTTY Group Austria GmbH | |
| Screenmaker.at | Lower Austria |
| Seasonax GmbH | |
| SecureGUARD GmbH | Upper Austria |
| seekda GmbH | Vienna |
| Seeyou | Vienna |
| Selsys GmbH | |
| Semantic Web Company | Vienna |
| Semanticlabs GmbH | Vienna |
| Semify GmbH | |
| Sensonic | |
| seoCon | |
| servus.at | |
| Seso Media Group GmbH | |
| Seza.me | |
| SG Connect Electronics Handelsgesellschaft mbH | Vienna |
| Sharobella | |
| Sheepblue GmbH | |
| Shopstory GmbH | |
| SIB Visions GmbH | |
| Sibelius | Carinthia |
| Siconnex Customized Solutions GmbH | |
| Sidebar | |
| Sigmatek GmbH & Co. KG | Salzburg |
| Sigmund Freud Privat Universität Wien | Vienna |
| Signa Holding GmbH | |
| SignPath GmbH | |
| Silberleithen GmbH | Tyrol |
| Silicon Austria Labs GmbH | |
| SiMAX | |
| SimpleWay Technologies GmbH | |
| Single Use Support | |
| SIS Informatik GmbH | |
| SIS Informationstechnologie GmbH | Vienna |
| SiTec GmbH | Vienna |
| SIWA Online GmbH | Upper Austria |
| Smaply GmbH | |
| Smart Education | |
| Smart Engine GmbH | |
| Smart Solutions e.U. | |
| Smart-Capital | |
| Smarter Ecommerce GmbH | Upper Austria |
| SMBS-University of Salzburg Business School GmbH | |
| SMF Produktions-, Handels- u. BeteiligungsgmbH | |
| smn Investment Services GmbH | |
| Snap Consulting - Systemnahe Anwendungsprogrammierung und Beratung GmbH | Vienna |