Recent independent studies highlight a significant shift in Iranian religious identity, often contradicting official government data.A landmark 2020 survey by theGroup for Analyzing and Measuring Attitudes in Iran (GAMAAN)found that only40% of Iranians identified as Muslim.
While your specific 37% figure appears in several contexts within these studies, it is often tied to specific beliefs rather than the total Muslim identification:
Belief vs. Identity:In the 2020 GAMAAN study, while 40% identified as Muslim, only37% believed in life after death.
Shia Identity Fluctuations:Subsequent GAMAAN surveys between 2022 and 2023 reported that those identifying specifically asShia Muslimfluctuated between32% and 37.9%.
Recent 2026 Estimates:Some unofficial reports as recent as February 2026 continue to cite a figure of roughly37% Muslimfor the population inside Iran, alongside a 62% irreligious majority.
Contrasting Data Sources
These independent findings represent a secular shift that contrasts sharply with other established datasets:
Official Census International Orgs:The Iranian governments 2011/2016 censuses and theCIA World Factbooktypically report over99% Muslim.
World Values Survey:A 2020 Wave 7World Values Surveyreported that96.6%of Iranians still identify as Muslim.
Pew Research Center:Pew Research Centerdata from 2025 continues to list Iran as overwhelmingly Muslim, though it notes that government restrictions on religion remain at peak levels.
Note on Methodology:GAMAAN uses anonymous online surveys to bypass state monitoring, which proponents argue captures more honest private beliefs in a country where apostasy can be a capital crime. Critics, however, suggest online-only surveys may overrepresent younger, more secular, or urban populations.
Would you like to see how thesereligious shiftscorrelate with recentpolitical attitudestoward the Iranian government?