Eastern Orthodoxy by country
Based on the numbers of adherents, the Eastern Orthodox Church (also known as Eastern Orthodoxy) is the second largest Christian communion in the world after the Roman Catholic Church. The most common estimates of the number of Eastern Orthodox Christians worldwide is approximately 200–260 million. The numerous Protestant groups in the world, if taken all together, outnumber the Eastern Orthodox, but they differ theologically and do not form a single communion.
Eastern Orthodoxy in North America
There may be as many as seven million people in the United States who self-identify as Orthodox due to ethnicity or being baptized as children. They may also be married in the church and baptize their children in the church, but they remain unknown to parishes and do not participate in church life. Many recent immigrants who have come to America also self-identify as Orthodox, but never participate in church life. The table below does not include either of these categories, limiting itself to those Orthodox believers who attend parish churches at least often enough to be counted in the official parish statistics. They are listed as "adherents." The "regular attendees" are the number of people who attend church on a typical Sunday.