SSN
- SIM Serial Number
- SN (disambiguation)
- SS (disambiguation)
- SSN (hull classification symbol)
- SSN (novel)
- SSN College of Engineering
- Scholars Strategy Network
- Scoil an Spioraid Naoimh
- Secure Service Network
- Semantic Sensor Web
- Seoul Air Base
- Servicio Sismológico Nacional
- Servizio Sanitario Nazionale
- Setanta Sports News
- Sky Sports News
- Social Security number
- Socialist Solidarity Network
- Società Storica Novarese
- Soul of the South Network
- South Sudan
- Space Surveillance Network
- Species Survival Network
- Stoom Stichting Nederland
- Subsystem number
- Suncorp Super Netball
- Superintendency of Insurance (Argentina)
- Superior salivatory nucleus
- Surgical segment navigator
- The Seed Savers' Network
- Tom Clancy's SSN