SNS
- Amazon Simple Notification Service
- SNS Bank
- Salinas Municipal Airport
- Salomon Nordic System
- Scuola Normale Superiore
- Serb People's Party (Montenegro)
- Serbian Progressive Party
- Serviço Nacional de Saúde
- Sistema Nacional de Salud
- Slovak National Party
- Slovak National Party (historical)
- Slovenian National Party
- Social networking service
- Société de natation de Strasbourg
- Somatic nervous system
- Spallation Neutron Source
- Special Night Squads
- Staines railway station
- Stoke Newington School
- Strategic National Stockpile
- Street News Service
- Super NES
- Supplemental nursing system
- Sympathetic nervous system
- Synthetic nervous system
- Tin(II) sulfide