Protestantism is the largest grouping of Christians in the United States, with its combined denominations comprising about 43% of the country's population (or 141 million people) in 2019. Other estimates suggest that 48.5% of the U.S. population (or 157 million people) is Protestant. This is the largest Protestant population of any country, around 20% of the world's total Protestant population. Baptists comprise about one-third of American Protestants. The Southern Baptist Convention is the largest single Protestant denomination in the U.S., comprising one-tenth of American Protestants. Twelve of the original Thirteen Colonies were Protestant, with only Maryland having a sizable Catholic population due to Lord Baltimore's religious tolerance.

The country's history is often traced back to the Pilgrim Fathers whose Brownist beliefs motivated their move from England to the New World. These English Dissenters, who also happened to be Puritans—and therefore Calvinists—were first to settle in what was to become the Plymouth Colony. America's Calvinist heritage is often underlined by various experts, researchers and authors, prompting some to declare that the United States was "founded on Calvinism", while also underlining its exceptional foundation as a Protestant majority nation.The Calvinist Roots of the Modern Era by Aliki Barnstone, Michael Tomasek Manson, Carol J. SingleyDavid L. Holmes. The Faiths of the Founding Fathers. American Protestantism has been diverse from the very beginning with large numbers of early immigrants being Anglican, various Reformed, Lutheran, and Anabaptist. In the next centuries, it diversified even more with the Great Awakenings throughout the country.

Protestants are divided into many different denominations, which are generally classified as either "mainline" or "evangelical", although some may not fit easily into either category. Some historically African-American denominations are also classified as Black churches. Protestantism had undergone an unprecedented development on American soil, diversifying into multiple branches, denominations, several interdenominational and related movements, as well as many other developments. All have since expanded on a worldwide scale mainly through missionary work.

Statistics

By tradition: Protestantism in the United States according to the Pew Research Center (2014) Affiliation% of U.S. population Protestant Evangelical Protestant Mainline Protestant Black church By identification as born-again or evangelical: Protestantism in the United States according to the Pew Research Center (2014) Affiliation% of U.S. population Protestant Born-again or evangelical Not born-again or evangelical By branch: Protestantism in the United States according to the Pew Research Center (2014) Affiliation% of U.S. population Protestant Baptist Nondenominational Protestant Methodist Pentecostal Unspecified Protestant Lutheran Presbyterian Restorationist Episcopalian/Anglican Holiness Congregationalist Adventist Anabaptist Other evangelical/fundamentalist other Reformed Pietist Quaker By denomination: Protestantism in the United States according to the Pew Research Center (2014) Affiliation% of U.S. population Protestant Other denomination Southern Baptist Convention United Methodist Church American Baptist Churches USA Churches of Christ Evangelical Lutheran Church in America National Baptist Convention, USA, Inc. Assemblies of God USA Lutheran Church-Missouri Synod Presbyterian Church (USA) Episcopal Church Church of God in Christ Seventh-day Adventist Church United Church of Christ Presbyterian Church in America Church of God (Cleveland, Tennessee)

Branches Baptists

Baptists are the largest Protestant grouping in the United States accounting for one-third of all American Protestants.

Baptist churches were organized, starting in 1814, as the Triennial Convention. In 1845, most southern congregations split, founding the Southern Baptist Convention, which is now the largest Protestant denomination in the U.S., with 12.3 million members as of 2025.Aaron Earls, Southern Baptists See Attendance and Baptism Gains Amid Membership Declines, research.lifeway.com, May 5, 2026 The Triennial Convention was reorganized into what is now American Baptist Churches USA and includes 1.1 million members and 5,057 congregations.SBC Summary of denominational statistics American Baptist Churches U.S.A.

African American Baptists, excluded from full participation in white Baptist organizations, have formed several denominations, of which the largest are the National Baptist Convention, and the more liberal Progressive National Baptist Convention.

There are numerous smaller bodies, some recently organized and others with long histories, such as the two original strands: the Particular Baptists and General Baptists, and the Free Will Baptists, Primitive Baptists, Strict Baptists, Old Regular Baptists, Two-Seed-in-the-Spirit Predestinarian Baptists, Independent Baptists, Seventh Day Baptists and others.

Baptists have been present in the part of North America that is now the United States since the early 17th century. Both Roger Williams and John Clarke, his compatriot in working for religious freedom, are credited with founding the Baptist faith in North America.Newport Notables In 1639, Williams established a Baptist church in Providence, Rhode Island (First Baptist Church in America) and Clarke began a Baptist church in Newport, Rhode Island (First Baptist Church in Newport). According to a Baptist historian who has researched the matter, "There is much debate over the centuries as to whether the Providence or Newport church deserved the place of 'first' Baptist congregation in America. Exact records for both congregations are lacking."Brackney, William H. (Baylor University, Texas). Baptists in North America: an historical perspective. Blackwell Publishing, 2006, p. 23.

Largest Baptist denominations The Handbook of Denominations in the United States identifies and describes 31 Baptist groups or conventions in the United States.Atwood, Craig D., Frank S. Mead, and Samuel S. Hill. Handbook of Denominations in the United States, 12th ed. Nashville, Tennessee: Abingdon Press, 2005. A partial list follows. (Unless otherwise noted, statistics are taken from the Baptist World Alliance website, and reflect 2006 data.)

Southern Baptist Convention: 46,608 congregations, 12.3 million members (2025) National Baptist Convention, USA, Inc.: 31,000 congregations, 7.5 million members (African-American) (2013) National Baptist Convention of America, Inc.: 12,000 congregations, 3.1 million members (African-American) Progressive National Baptist Convention: 1,200 congregations, 2.5 million members (African-American) Baptist General Convention of Texas: 4,200 congregations, 1.7 million members2019 Texas baptists annual meeting Baptist Bible Fellowship International: 3,400 congregations, 1.4 million members American Baptist Churches USA: 5,100 congregations, 1.1 million members

Presbyterian

Presbyterians largely came from Scotland or Ulster (Northern Ireland today) to the Middle Colonies, most commonly Pennsylvania. Princeton University was established in 1746 by Presbyterians (Particularly Jonathan Dickinson and Aaron Burr Sr.) to rigorously educate clergymen in alignment to the theology pioneered by William Tennent, and later went on to produce the "Princeton Theologians" such as Charles Hodge.

Under the influence of Scottish theologians like Samuel Rutherford and John Knox, Presbyterians largely believed in the idea that "Resistance to tyranny is obedience to God." Vastly in fervent support of the American Revolution, the Revolutionary War was dubbed the "Presbyterian Rebellion" by King George III and other loyalists.

The first ministers were recruited from Northern Ireland. While several Presbyterian churches had been established by the late 1600s, they were not yet organized into presbyteries and synods until the early 1700s.

Presbyterian Church (U.S.A.) mainline church has approximately 1,019,000 members and 8,304 congregations. It adopted the Book of Confessions which include the Westminster Confession. Headquarters is in Louisville, Kentucky. Presbyterian Church in America Evangelical, Calvinist church, adheres to the Westminster Confession of Faith. The denomination has 374,000 members and 1912 congregations and several congregation outside the United States, in Germany, Japan, Cayman Islands, etc. Headquarters is located in Lawrenceville, Georgia. Evangelical Presbyterian Church (United States) has more than 600 congregations and 145,000 members. Adhere to the Westminster Confession. Evangelical Reformed Church in America Orthodox Presbyterian Church was formed in 1936 under the influence of John Gresham Machen, has 31,000 members. Evangelical Covenant Order, 60,000 members in 357 congregations. Bible Presbyterian Church Associate Reformed Presbyterian Church Free Presbyterian Church in North America Reformed Presbyterian Church in North America Cumberland Presbyterian Church Cumberland Presbyterian Church in America Free Reformed Church in North America Reformed Church in America Christian Reformed Church in North America Netherlands Reformed Congregations Hungarian Reformed Church in America

Lutheranism

With 2.6 million members, the Evangelical Lutheran Church in America (ELCA) is the largest American Lutheran denomination, followed by the Lutheran Church–Missouri Synod (LCMS) with 1.7 million members, and the Wisconsin Evangelical Lutheran Synod (WELS) with 344,000 members. The differences between the Evangelical Lutheran Church in America (ELCA) and the Lutheran Church–Missouri Synod (LCMS) largely arise from historical and cultural factors, although some are theological in character. The ELCA tends to be more involved in ecumenical endeavors than the LCMS.

When Lutherans came to North America, they started church bodies that reflected, to some degree, the churches left behind. Many maintained their immigrant languages until the early 20th century. They sought pastors from the "old country" until patterns for the education of clergy could be developed in America. Eventually, seminaries and church colleges were established in many places to serve the Lutheran churches in North America and, initially, especially to prepare pastors to serve congregations.

The LCMS sprang from German immigrants fleeing the forced Prussian Union, who settled in the St. Louis area and has a continuous history since it was established in 1847. The LCMS is the second largest Lutheran church body in North America (1.7 million). It identifies itself as a church with an emphasis on biblical doctrine and faithful adherence to the historic Lutheran confessions. Insistence by some LCMS leaders on a strict reading of all passages of Scripture led to a rupture in the mid-1970s, which in turn resulted in the formation of the Association of Evangelical Lutheran Churches, now part of the ELCA.

Although its strongly conservative views on theology and ethics might seem to make the LCMS politically compatible with other Evangelicals in the U.S., the LCMS as an organization largely eschews political activity, partly out of its strict understanding of the Lutheran distinction between the Two Kingdoms. It does, however, encourage its members to be politically active, and LCMS members are often involved in political organizations such as Lutherans for Life.