The U.S. government estimates the total population at 82.0 million (midyear 2020 estimate). According to the Turkish government, 99 percent of the population is Muslim, approximately 77.5 percent of which is Hanafi Sunni. Representatives of other religious groups estimate their members are 0.2 percent of the population, while the most recent public opinion surveys published in January 2019 by Turkish research firm KONDA suggest approximately 3 percent of the population self-identifies as atheist and 2 percent as nonbelievers.

Leaders of Alevi foundations estimate Alevis comprise 25 to 31 percent of the population; Pew Research Center reporting indicates 5 percent of Muslims state they are Alevis. The Shia Jafari community estimates its members make up 4 percent of the population.

Non-Muslim religious groups are mostly concentrated in Istanbul and other large cities, as well as in the southeast. Exact figures are not available; however, these groups self-report approximately 90,000 Armenian Apostolic Orthodox Christians (including migrants from Armenia), 25,000 Roman Catholics (including migrants from Africa and the Philippines), and 16,000 Jews. There are also approximately 25,000 Syrian Orthodox Christians (also known as Syriacs), 15,000 Russian Orthodox Christians (mostly immigrants from Russia who hold residence permits), and 10,000 Baha’is.

Estimates of other groups include 7,000-10,000 members of Protestant denominations, 5,000 Jehovah’s Witnesses, fewer than 3,000 Chaldean Christians, up to 2,500 Greek Orthodox Christians, and fewer than 1,000 Yezidis. There also are small, undetermined numbers of Bulgarian Orthodox, Nestorian, Georgian Orthodox, Ukrainian Orthodox, Syriac Catholic, Armenian Catholic, Chaldean Catholic, and Maronite Christians. The Church of Jesus Christ of Latter-day Saints (Church of Jesus Christ) estimates its membership at 300 individuals.