Christianity is the largest religion in the United States, practiced by roughly 65% of adults, followed by a large religiously unaffiliated group at about 26% and smaller communities of Jews, Muslims, Buddhists, and Hindus. The country has no official state religion; instead, the First Amendment guarantees both freedom of religion and the separation of church and state, producing one of the most religiously varied societies on Earth.
Religious Demographics at a Glance
The American religious landscape is broad but Christian-majority. Estimates from major surveys break down roughly as follows:
- Christianity: ~65% of the population, split mainly between Protestants (~43%) and Catholics (~20%), plus other Christian traditions such as the Latter-day Saints and Orthodox churches.
- Unaffiliated ("Nones"): ~26%, including atheists, agnostics, and those who say their religion is "nothing in particular."
- Judaism: ~2%, the second-largest Jewish population of any country after Israel.
- Islam: ~1%, a young and fast-growing community concentrated in metro areas.
- Buddhism and Hinduism: roughly 1% each, largely tied to immigration from Asia.
Protestantism itself is not monolithic. It spans evangelical denominations, historically Black churches, and mainline bodies like Methodists, Lutherans, Presbyterians, and Episcopalians, each with distinct theology and culture.
How Religion Shaped American History
Religion has been woven into the United States since the colonial era. Puritans and Pilgrims arrived in 17th-century New England seeking freedom to worship on their own terms, while Quakers, Catholics, and others found refuge in colonies such as Pennsylvania and Maryland. After independence, the First Amendment (ratified in 1791) barred Congress from establishing a religion or restricting its free exercise.
A series of religious revivals known as the Great Awakenings, in the 18th and 19th centuries, energized evangelical Protestantism and helped shape American democratic and reform movements, including abolitionism. The 19th and early 20th centuries brought waves of Catholic immigrants from Ireland, Italy, and Poland, along with large Jewish communities from Central and Eastern Europe. Later immigration from Asia and the Middle East added thriving Muslim, Hindu, Buddhist, and Sikh populations, transforming the religious map yet again.
The Rise of the "Nones"
The most striking trend of recent decades is the rapid growth of the religiously unaffiliated. Once a small minority, the "Nones" now make up roughly a quarter of all adults and are even more numerous among younger generations. This shift reflects declining membership in many mainline Protestant and Catholic congregations, even as evangelical and nondenominational churches remain strong.
Despite secularizing trends, the United States remains noticeably more religious than most other wealthy democracies. About 40% of Americans say they attend religious services at least monthly, and faith continues to influence politics, education, charity, and daily life in ways that set the country apart from Western Europe.
Worship, Culture, and Geography
Religious practice in America is regional and varied. The Southern "Bible Belt" is heavily evangelical Protestant, Utah is overwhelmingly Latter-day Saint, the Northeast has deep Catholic roots, and coastal cities tend to be the most religiously diverse and secular. Megachurches, congregations of 2,000 or more worshippers, are a distinctly American phenomenon, with more than a thousand spread across the country.
Major holidays such as Christmas and Easter blend religious meaning with secular celebration, and religious broadcasting, televangelism, and faith-based charities form sizable industries. Landmarks reflect this diversity, from Washington National Cathedral and New York's St. Patrick's Cathedral to Salt Lake City's Temple Square and Rhode Island's Touro Synagogue, the oldest surviving synagogue in the country, dating to 1763. For more on the nation's geography, culture, and people, see our united-states country guide.
Religion and Public Life
Although there is no national church, religious language remains visible in civic life. The phrase "In God We Trust" became the official national motto in 1956, and "under God" was added to the Pledge of Allegiance in 1954, both Cold War-era affirmations. Religious organizations are also the single largest category of charitable giving in the United States, receiving roughly a third of all donations. At the same time, courts continually interpret the balance between free exercise of religion and the constitutional ban on establishing one, making church-state questions a recurring feature of American legal debate.
Frequently Asked Questions
What is the most common religion in the United States?
Christianity is by far the most common, practiced by about 65% of the population. Protestants form the largest Christian group, followed by Roman Catholics.
Does the United States have an official religion?
No. The First Amendment to the Constitution prohibits the government from establishing an official religion and protects the free exercise of all faiths, creating a clear separation of church and state.
Are Americans becoming less religious?
In some ways, yes. The share of religiously unaffiliated adults has grown to about a quarter of the population, especially among younger generations. Even so, the United States remains more religious than most other developed nations.
Which religions are growing fastest in the United States?
The religiously unaffiliated are the fastest-growing group overall, while Islam, Hinduism, and Buddhism have expanded steadily through immigration and have relatively young populations.