The U.S. government estimates the total population at 41.7 million (July 2018 estimate), more than 99 percent of whom are Muslims following the Maliki school of Sunni Islam.  Religious groups together constituting less than 1 percent of the population include Christians, Jews, Ahmadi Muslims, Shia Muslims, and a community of Ibadi Muslims residing principally in the province of Ghardaia.  Some religious leaders estimate there are fewer than 200 Jews.

The Christian community includes Roman Catholics, Seventh-day Adventists, Methodists, members of the EPA, Lutherans, the Reformed Church, Anglicans, and an estimated 1,000 to 1,500 Egyptian Coptic Christians.  Religious leaders’ unofficial estimates of the number of Christians range from 20,000 to 200,000.  According to government officials, foreign residents make up the majority of the Christian population.  The proportion of students and immigrants without legal status from sub-Saharan Africa among the Christian population has also increased in recent years.  Christian leaders say citizens who are Christians predominantly belong to Protestant groups.

Christians reside mostly in the cities of Algiers, Bejaia, Tizi Ouzou, Annaba, and Oran, and the Kabylie region east of the capital.

The U.S. government estimates the total population at 9.5 million (July 2018 estimate).  According to a January 2016 survey by the state Information and Analytical Center of the Presidential Administration, approximately 53 percent of the adult population belongs to the BOC and 6 percent to the Roman Catholic Church.  According to the state survey, 8 percent of the adult population is atheist, and 22 percent is “uncertain.”  Smaller religious groups together constituting approximately 2 percent of the population include:  Jews; Muslims; Greek Catholics (“Uniates”); Old Believers (priestist and priestless); members of the Belarusian Autocephalous Orthodox Church, and other Orthodox Christian groups, Lutherans, Jehovah’s Witnesses, Apostolic Christians, Presbyterians and other Protestant groups, Armenian Apostolics, Latin Catholics, members of the International Society of Krishna Consciousness, Baha’is, members of The Church of Jesus Christ of Latter-day Saints, and Buddhists.  Jewish groups state there are between 30,000 and 40,000 Jews.  Ethnic Poles, who constitute approximately 3 percent of the population, tend to be Roman Catholic.