The U.S. government estimates the total population at 54.3 million (July 2016 estimate). According to a 2010 Pew Research Center report, 81 percent of the population is Christian. Approximately 15 percent of the population adheres to no particular religion or declined to indicate an affiliation; some of these individuals are likely adhere to indigenous beliefs. Muslims constitute 1.7 percent of the population, while Hindus, Jews, Buddhists, and adherents of traditional indigenous beliefs together constitute less than 4 percent of the population. Many indigenous persons adhere to a belief system combining Christian and indigenous religious practices. The Church of Scientology estimates it has approximately 100,000 members.

The Pew Research Center estimates 84 percent of the Christian population is Protestant, 11 percent Catholic, and 5 percent other denominations (2010 estimate). African independent churches constitute the largest group of Christian churches, including the Zion Christian Church (approximately 11 percent of the population), the Apostolic Church (approximately 10 percent), and a number of Pentecostal and charismatic groups. Other Christian groups include Methodists, Anglicans, Baptists, Lutherans, Presbyterians, Roman Catholics, Seventh-day Adventists, and members of the Greek Orthodox, Dutch Reformed, and Congregational churches.

Persons of Indian or other Asian heritage account for 2.5 percent of the total population. Roughly half of the ethnic Indian population is Hindu, and the majority resides in KwaZulu-Natal Province. The Muslim community includes Cape Malays of Malayan-Indonesian descent, individuals of Indian or Pakistani descent, and approximately 70,000 Somali nationals and refugees. The SAJBD estimates the Jewish community at 75,000 to 80,000 persons, the majority of whom live in Johannesburg and Cape Town.