More people have left Catholicism than joined in most countries: report

(LifeSiteNews) — Many more people have left the Catholic faith since childhood than converted to it, Pew Research Center has found.

Over the past several decades, Catholicism has lost more adherents than it has gained in “nearly all countries” around the world surveyed by Pew Research in 2024, according to its report published on Thursday.

“In Italy, for instance, 22% of all adults say they were raised Catholic and no longer identify as such, while 1% were not raised Catholic but have since joined the religion. This results in a net loss of 21 percentage points in the Catholic population in Italy due to religious switching,” explained Pew Research.

The numbers show that in many places around the world, but especially in traditionally Catholic Western Europe and Latin America, the Church has been hemorrhaging its faithful. Spain has suffered especially great losses, with 34 percent of adults saying they were raised Catholic and have left the faith. In Chile and France, that percentage of adults is 26; in Brazil it is 25; in Argentina and Mexico it is 21.

By contrast, the percentage of adults who say they have converted to Catholicism in these countries for the most part hovers at about 2 percent. Hungary is the only country surveyed in which more people have converted to the Catholic faith (5 percent) than left it (2 percent).

In the U.S., where a large share of adults identify as Protestant Christian, 13 percent of adults surveyed said they were raised Catholic and left the faith. 

It should be noted that among those who still identify as Catholic, actual religious practice is not accounted for, meaning self-identified Catholics may not be practicing Catholics, and in many cases they do not attend Mass weekly.

Those who leave Catholicism “tend to join Protestantism or disaffiliate from religion altogether,” according to Pew Research.

While the surveys found that Protestantism has seen a net loss overall around the world, it has had a net gain from converts in “nearly as many places as it has seen a net loss,” reported Pew Research. Most of the countries where Protestantism has seen a net gain are in Latin America. Those with especially high numbers of converts to Protestantism are Brazil (15 percent of adults surveyed) and Peru (11 percent).

READ: Why are young men more religious than young women?

“Adults who leave Protestantism tend to become religiously unaffiliated,” noted Pew. Especially high numbers of such adults are found in Sweden, the United Kingdom, and Germany.

Discerning the causes of decline in Catholic affiliation is not entirely straightforward, in part because Catholic self-identification and religious practice are distinct in Pew surveys. However, the clearest pattern that has emerged worldwide over the past century is a decline in Catholic practice after the Second Vatican Council, which was held from 1962 to 1965.

A secular study published last year found that Vatican II “triggered a decline” in worldwide Catholic Mass attendance relative to religious service attendance of other religions, including Protestant Christianity.

By examining the religious service attendance rates for 66 countries as far back as 1920, the National Bureau of Economic Research (NBER) found that “compared to other countries, Catholic countries experienced a steady decline in the monthly adult religious service attendance rate starting immediately after Vatican II” in 1965, the final year of the council.

Catholic countries were defined as those with a Catholic population of 50 percent or greater and included nations such as Ireland, Italy, Austria, France, Brazil, the Philippines, and Mexico. 

A graph representing the researchers’ data shows that monthly religious service attendance in Catholic countries decreased by at least 20 percentage points relative to that of all other countries as well as relative to “Christian” countries, with a significant decline seen first in the period from 1965 to 1974. Mass attendance in Catholic countries fell on average by four percentage points per decade from 1965 to 2015.

These findings accord with those of French historian Guillaume Cuchet, who in 2022 published an analysis that found 1965, the year the Second Vatican Council ended, marked the beginning of the “collapse” of the practice of Catholicism in France.

It was in 1965 that significant changes to the Mass began with the implementation of Inter oecumenici, such as the offering of the Mass facing the people and the reading of the lessons by laypeople. As Cuchet noted in reference to declining Mass attendance, while these changes in ritual may seem “secondary to intellectuals,” they “are actually psychological and anthropological determinants.”

While the Catholic Church has a long way to go if it is to make up for its losses, a recent worldwide surge in Catholic converts recorded as of 2025 and 2026 is cause for hope. Adult converts to the Catholic Church in the U.S. have risen by about 38 percent this year, with the U.K., Ireland, France, Spain, Sweden, and Norway having recorded a similar uptick in adult Catholic converts. 

Last year, the Conference of Bishops in France (CEF) recorded the largest number of catechumens to be received or baptized into the Church since records began about 20 years ago.