S-300

The S-300 is a family of long-range surface-to-air missile systems developed by the Soviet Union and manufactured by Almaz-Antey in Russia. Iran's variant — the S-300PMU-2 — was delivered in 2016 after Russia lifted a self-imposed arms embargo following the 2015 JCPOA nuclear deal. Iran operates the system to protect strategic sites including nuclear facilities at Fordow and Natanz and the Isfahan enrichment complex.

In the context of the 2026 conflict, the S-300's limitations became tactically significant: the system is designed to intercept high-altitude aircraft and Ballistic Missiles but is less effective against low-observable Cruise Missiles, saturation attacks, and electronic warfare. Israeli and US strikes early in the conflict degraded several S-300 batteries using a combination of AARGM-ER anti-radiation missiles and decoy drones. Russia has not offered replacement systems or spare parts under wartime conditions, citing its own consumption in Ukraine.

The S-300 family also equips several NATO and EU member states, creating interoperability and intelligence-sharing sensitivities that shaped Western decisions about which munitions to share with Israel. Russian exports of the system to Syria, Belarus, and Algeria have made the S-300's operational record closely studied by NATO planners.