Catholic decline is sharpest, as Nones contribute to falling affiliation.
For the first time, membership in houses of worship has dropped below 50% in the United States, according to Gallup. The largest declines are in the Catholic Church.
The 47% of Americans who told the polling organization that they belong to a church, synagogue or mosque is a far cry from the 70% who said that just 22 years ago, in 1999.
Gallup has been keeping track of church membership since 1937, when it found a 73% membership rate. It remained near 70% for six decades, but began a steady decline around the turn of the 21st century.
“The decline in church membership is primarily a function of the increasing number of Americans who express no religious preference,” Gallup said. “Over the past two decades, the percentage of Americans who do not identify with any religion has grown from 8% in 1998-2000 to 13% in 2008-2010 and 21% over the past three years.” A summary from Gallup states:
Given the nearly perfect alignment between not having a religious preference and not belonging to a church, the 13-percentage-point increase in no religious affiliation since 1998-2000 appears to account for more than half of the 20-point decline in church membership over the same time. Most of the rest of the drop can be attributed to a decline in formal church membership among Americans who do have a religious preference.
Church membership is strongly correlated with age, Gallup said, as 66% of “traditionalists” — Gallup’s term for U.S. adults born before 1946 — belong to a church, compared with 58% of baby boomers, 50% of those in Generation X and 36% of millennials. “The limited data Gallup has on church membership among the portion of Generation Z that has reached adulthood are so far showing church membership rates similar to those for millennials,” the organization said.
Currently, 31% of millennials have no religious affiliation, which is up from 22% a decade ago, Gallup said. Similarly, 33% of the portion of Generation Z that has reached adulthood have no religious preference.
The survey does not herald good news for the Catholic Church:
Among religious groups, the decline in membership is steeper among Catholics (down 18 points, from 76% to 58%) than Protestants (down nine points, from 73% to 64%). This mirrors the historical changes in church attendance Gallup has documented among Catholics, with sharp declines among Catholics but not among Protestants.
In spite of all this, Gallup found the U.S. to still be a religious nation, with more than seven in 10 affiliating with some type of organized religion. “However, far fewer, now less than half, have a formal membership with a specific house of worship,” the organization said. “While it is possible that part of the decline seen in 2020 was temporary and related to the coronavirus pandemic, continued decline in future decades seems inevitable, given the much lower levels of religiosity and church membership among younger versus older generations of adults. … The challenge for church leaders is to encourage those who do affiliate with a specific faith to become formal, and active, church members.”