The U.S. government estimates the population at 85.0 million (midyear 2020 estimate). According to Iranian government estimates, Muslims constitute 99.4 percent of the population, of whom 90-95 percent are Shia, and 5-10 percent are Sunni, mostly Turkmen, Arabs, Baluchis, and Kurds, living in the northeast, southwest, southeast, and northwest provinces, respectively. Afghan refugees, economic migrants, and displaced persons also make up a significant Sunni population, but accurate statistics on the breakdown of the Afghan refugee population between Sunni and Shia are unavailable. There are no official statistics available on the number of Muslims who practice Sufism, although unofficial reports estimate several million.

According to U.S. government estimates, groups constituting the remaining less than 1 percent of the population include Baha’is, Christians, Yarsanis, Jews, Sabean-Mandaeans, and Zoroastrians. The three largest non-Muslim minorities are Baha’is, Christians, and Yarsanis.

According to Human Rights Watch data, Baha’is number at least 300,000.

The government Statistical Center of Iran reports there are 117,700 Christians in the country. Some estimates, however, suggest there may be many more than actually reported. According to World Christian Database statistics, there are approximately 547,000 Christians. Elam Ministries, a Christian organization, estimates there could be between 300,000 and one million.

Estimates by the Assyrian Church of the total Assyrian and Chaldean Christian population put their combined number at 7,000. There are also Protestant denominations, including evangelical groups, but there is no authoritative data on their numbers. Christian groups outside the country disagree on the size of the Protestant community, with some estimates citing figures lower than 10,000, and others, such as Open Doors USA, citing numbers greater than 800,000. Many Protestants and converts to Christianity from Islam reportedly practice in secret.

There is no official count of Yarsanis, but HRANA and the Center for Human Rights in Iran (CHRI) estimate there are up to two million. Yarsanis are mainly located in Loristan and the Kurdish regions.

According to recent estimates from Armenian Christians who maintain contact with the Iranian Christian community in the country, their current numbers are approximately 40,000 to 50,000, significantly lower than the peak of 300,000 estimated prior to 1979. The number of Roman Catholics in the country is estimated to be 21,000.

According to Zoroastrian groups and the government-run Statistical Center of Iran, the population includes approximately 25,000 Zoroastrians.

According to the Tehran Jewish Committee, the population includes approximately 9,000 Jews, while representatives from the Jewish community in the country estimated their number at 15,000 during a 2018 PBS News Hour interview.

The population, according to government media, includes 14,000 Sabean-Mandaeans.

According to the 2011 census, the number of individuals who are nonreligious rose by 20 percent between 2006 and 2011, which supports observations by academics and others that the number of atheists, agnostics, nonbelievers, and religiously unaffiliated living in the country is growing. Often these groups, however, do not publicly identify, as documented by Amnesty International’s report on the country, because those who profess atheism are at risk of arbitrary detention, torture, and the death penalty for “apostasy.”

According to IranWire, during Friday prayers in early November in Kermanshah, Sunni cleric Mullahamid Faraji called Yarsanis infidels, Satanists, and enemies of Muslims. “Yarsanis are not our brothers,” he told the congregation, adding, “Brotherhood is only possible in Islam.” According to IranWire, protests by members of the Yarsan community followed, gaining momentum over the days that followed, prompting Faraji to issue a retraction on social media in which he said enemies of the Islamic Republic had distorted and misrepresented his statements in an attempt to sow division between Muslims and Yarsanis in the area. He defined these “enemies” as Jews, Christians, and Zionists.

According to Radio Farda, Molavi Abdolhamid Ismaeelzahi, the most senior Sunni cleric in the country, circulated a video on social media charging that Chinese Shia students studying at al-Mustafa International University had infected Iran with the novel coronavirus. The university said in a statement that the Sunni leader had no evidence to back up his accusation and that top religious clerics should be more cautious in public remarks. According to Iran News, the university also “deplored Abdolhamid for accusing al-Mustafa International University of brainwashing its non-Iranian students.”

A member of the Sabean-Mandaean community in Ahvaz said that he had witnessed the destruction of a temple and 12 other buildings belonging to the community in recent years. Another Sabean-Mandaean said, “Since 2015, the destruction of the Mandaean tombs has occurred many times in different parts of the country. But have our protests ever been heeded?”

According to a Radio Farda report, Yarsani graves were neither safe from attacks nor from disrespect, and Yarsani cemeteries and mausoleums were repeatedly damaged and destroyed in the city of Kermanshah and elsewhere in the country.

According to press and NGO reports, on May 14, following threats on Twitter, a man broke into the shrine of Esther and Mordechai, a Jewish holy site in Hamadan, in an attempt to set fire to the tomb. IRNA, the country’s official press agency, which first confirmed the attack but later removed the report from its website, said there was no major damage to the shrine. The attack followed reports in February that the government was considering razing the shrine as an act of revenge aimed at the United States and Israel. Hamedan’s prosecutor, Hassan Khanjani, told the semiofficial ISNA news agency that police had not reached a conclusion on the cause of the fire and that no arrests had been made.

Baha’is and those who advocated for their rights reported that Baha’is continued to be major targets of social stigma and violence and that perpetrators reportedly continued to act with impunity.

There continued to be reports of non-Baha’is dismissing or refusing employment to Baha’is, sometimes in response to government pressure, according to BIC and other organizations monitoring the situation of Baha’is. BIC continued to report instances of physical violence committed against Baha’is based on their faith. Baha’is reported there were continued incidents of destruction or vandalism of their cemeteries.

Yarsanis outside the country reported that widespread discrimination against Yarsanis continued. They stated Yarsani children were socially ostracized in school and in shared community facilities. Yarsani men, recognizable by their particular mustaches, continued to face employment discrimination. According to reports, Shia preachers continued to encourage social discrimination against Yarsanis.

According to human rights NGOs, including CSW, Open Doors USA, and others, converts from Islam to Christianity faced ongoing societal pressure and rejection by family or community members.

Shia clerics and prayer leaders reportedly continued to denounce Sufism and the activities of Sufis in both sermons and public statements.

Sunni students reported professors continued to routinely insult Sunni religious figures in class.

In June, the Netherlands-based NGO Group for Analyzing and Measuring Attitudes in Iran conducted an online survey with the collaboration of the ABC that showed Iranian society’s unprecedented secularization. According to its authors, the result of the poll of 40,000 individuals revealed dramatic changes in the country’s religiosity, with an increase in secularization and a diversity of faiths and beliefs. The survey found that only 40 percent of respondents identified as Muslim, contrasting with government data that states 99.5 percent of the country is Muslim. The survey found 32 percent of respondents explicitly identified as Shia, while 5 percent said they were Sunni Muslim and 3 percent Sufi Muslim. Another 9 percent said they were atheists, along with 7 percent who preferred the label of “spirituality” as describing their religion. Among the other selected religions, 8 percent said they were Zoroastrians, which the pollsters interpreted as a reflection of Persian nationalism and a desire for an alternative to Islam, rather than strict adherence to the Zoroastrian faith, while 1.5 percent said they were Christian (which Christian groups state translates into between 750,000 and one million Christians in the country). Of those polled, 78 percent said they believed in God, while only 37 percent believed in life after death and only 30 percent believed in heaven and hell. Approximately 25 percent said they believed in jinns (demons).