The U.S. government estimates the total population at 10.3 million (midyear 2021).  According to 2011 SCWRA data (the most recent available), 96 percent of the population is Muslim, of which approximately 65 percent is Shia and 35 percent Sunni.  Groups that together constitute the remaining 4 percent of the population include the Russian Orthodox Church; Georgian Orthodox Church; Armenian Apostolic Church; Seventh-day Adventists; Molokan Church; Roman Catholic Church; other Christians, including evangelical churches, Baptists, and Jehovah’s Witnesses; Jews; and Baha’is.  Ethnic Azerbaijanis are mainly Muslims, and non-Muslims are mainly Russians, Georgians, Armenians, and other national minorities.  Others include the International Society of Krishna Consciousness and those professing no religion.

Christians live mainly in Baku and other urban areas.  Approximately 15,000 to 20,000 Jews live in Baku, with smaller communities throughout the country.