Christianity by country

As of the early 21st century, Christianity has approximately 2.4 billion adherents, out of about 7.2 billion people. The faith represents approximately one-third of the world's population and is the largest religion in the world, with the three largest groups of Christians being the Catholic Church, Protestantism, and the Eastern Orthodox Church. The largest Christian denomination is the Catholic Church, with 1.09 billion adherents. The second largest Christian branch is either Protestantism (if it is considered a single group), or the Eastern Orthodox Church (if Protestants are considered to be divided into multiple denominations).

Christianity is the predominant religion in Europe, Russia, the Americas, the Philippines, East Timor, Southern Africa, Central Africa, East Africa and Oceania. There are also large Christian communities in other parts of the world, such as Indonesia, Central Asia and the Middle East, where Christianity is the second-largest religion after Islam. The United States of America has the largest Christian population in the world, followed by Brazil and Mexico.

Christianity, in one form or another, is the state religion of the following 15 nations: Argentina (Roman Catholic Church),Armenia (Armenian Apostolic Church) Tuvalu (Church of Tuvalu), Tonga (Free Wesleyan Church of Tonga), Costa Rica (Roman Catholic Church),Kingdom of Denmark (Danish National Church),England (Church of England), Greece (Eastern Orthodox Church), Georgia (Eastern Orthodox Church),Iceland (Church of Iceland),Liechtenstein (Catholic Church),Malta (Catholic Church),Monaco (Catholic Church),Vatican City (Catholic Church), and Zambia.

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