| Students International Travel Association | Academic & Science |
| Spirit Industry Trade Association | Business |
| Scuba Industries Trade Association | Business |
| Société Internationale de Télécommunications Aéronautiques (in French) International Aeronautical Telecommunications Society | Business |
| South African State Information Technology Agency | Business |
| Société International de Télécommunications Aeronautiques | Community |
| Southtowns Invitational Track Association | Community |
| Student Instructional Technology Assistants | Computing |
| Societe Internationale Telecommunications Aeronautiques | Computing |
| Société Internationale de Télécommunications Aéronautiques | Computing |
| Stop Islamisation and Terrorist Actions | General |
| Sleeping In The Aviary | General |
| Sensitivity In True Action | General |
| Something In The Air | General |
| Societa Italiana Trasporti Automobilistici | General |
| Societe Industrielle des Transports Automobiles | General |
| South India Term Abroad | General |
| Società Italiana Trasporti Automobilistici | General |
| Self Insertion Theatrics Automaton | General |
| Supporting Indian Trade and | General |
| Sacred India Tarot Arcana | General |
| Screen In The Air | General |
| Suppression of Immoral Traffic Act | Governmental |
| Student International Travel Association | International |
| Sindicato Independiente del Transporte Aéreo | International |
| Society for International Telecommunications for Aeronautics | International |
| Swedish Interactive Thresholding Algorithm | Medical |
| Safe Impeccable Timely Action | Military and Defence |
| Service Information and Technology Architecture | Softwares |
| Sahaja Internet Team Administration | Softwares |
| Societe Internationale De Telecommunications Aeronautiques | Space Science |
| State Information Technology Agency | Technology |
