86% of immigrants express a religious affiliation. This is much higher than for the United States as a whole, where 77% say they are affiliated. In other words, immigrants increase the number of persons who practice a religion.
According to Pew Research, while Christians continue to make up a majority of legal immigrants to the U.S., the estimated share of new legal permanent residents who are Christian declined from 68% in 1992 to 61% in 2012. Over the same period, the estimated share of green card recipients who belong to religious minorities rose from approximately one-in-five (19%) to one-in-four (25%). This includes growing shares of Muslims (5% in 1992, 10% in 2012) and Hindus (3% in 1992, 7% in 2012). The share of Buddhists, however, is slightly smaller (7% in 1992, 6% in 2012), while the portion of legal immigrants who are religiously unaffiliated (atheist, agnostic or nothing in particular) has remained relatively stable, at about 14% per year.
Unauthorized immigrants, by contrast, come primarily from Latin America and the Caribbean, and the overwhelming majority of them – an estimated 83% – are Christian. That share is slightly higher than the percentage of Christians in the U.S. population as a whole (estimated at just under 80% of U.S. residents of all ages, as of 2010).