Religion in Iran: Communities, History and What the Numbers Mean

Which religious communities live in Iran?

The U.S. Department of State’s report for 2023 describes Shi‘a and Sunni Muslims alongside Bahá’ís, Christians, Jews, Zoroastrians, Yarsanis and Sabean-Mandaeans, as well as Sufi adherents. Its Christian inventory includes Armenian and Assyrian communities, Catholics, Protestants and converts. These categories should not be treated as a precise population table: the report itself notes gaps and competing estimates. [2]

Sunni communities are also geographically and culturally varied. The same report identifies Sunni populations among several groups, including Kurds, Baluch, Turkmen and Arabs in different regions. This does not mean that every member of any of those ethnic groups has the same religion. Ethnicity, language, citizenship and religious affiliation answer different questions about a person or community. [2]

Why religious population figures need context

Pew Research Center’s global composition table, published in June 2025, estimates that Muslims represented 99.8% of Iran’s population in 2020. The estimate’s year matters: it is not a new 2026 measurement. Nor does a broad affiliation category tell us how often people pray, how they interpret their tradition or whether they agree with government policy. [3]

Pew’s methodology explains that Iran’s national census supplies its figures. It also discusses anonymous online surveys by GAMAAN that produce substantially different results. Those surveys use nonprobability sampling and demographic weighting. Pew did not use them for its 2010–2020 comparison, citing the lack of a 2010 baseline and, at publication, the absence of replication by other organizations. [4]

This disagreement is a reason to read the methods alongside the headline number. A census category and an anonymous online response are different forms of evidence, gathered under different conditions. Pew explicitly considers how people may express identity differently. Combining incompatible estimates into a single confident percentage would hide those differences rather than resolve them. [4]

Religious diversity in the built landscape

Yazd makes several strands of religious heritage visible within one city. UNESCO’s account of its historic urban landscape includes mosques, synagogues and Zoroastrian temples alongside earthen homes, markets and water systems. These buildings provide concrete evidence of different community histories. A heritage description, however, is not a nationwide assessment of present-day equality or freedom of worship. [5]

Northwestern Iran’s UNESCO-listed Armenian Monastic Ensembles comprise St Thaddeus, St Stepanos and the Chapel of Dzordzor. Their buildings and continuing religious significance connect Iran with Armenian Christian history. St Thaddeus is a pilgrimage site. These monuments belong in an account of religion in Iran even when the country is introduced through its official Islamic identity. [6]

Recognition and lived conditions are separate questions

A March 2026 report by the UN Special Rapporteur on Iran, covering January 2025 through February 2026, describes persecution of Bahá’ís, including arrests, property confiscation and exclusion from higher education and employment. It also reports targeting of Christians, particularly converts, while distinguishing Christianity’s constitutional recognition from the position of Bahá’ís. These are attributed findings from a dated report, not a description of every individual experience. They show why legal recognition and actual conditions need separate examination. [7]