Disaffiliation from religion not limited to U.S. but is an international phenomenon
Christianity and Buddhism are hardest hit while defections from Islam are few
The phenomenon of people changing their religious beliefs is far from limited to the United States: An analysis of interviews of more than 40,000 people in 36 countries1 throughout the world found a median rate2 of 21 percent of adults have switched their religious affiliation since childhood — most often to “nothing in particular” or some other form of nonreligious belief.
And substantial lifetime religious changes were true not just for Christianity, as in the United States, but also for Buddhism. Changes in affiliations from the other major religions of Islam, Hinduism and Judaism were far less common.
The numbers come from the nonpartisan Pew Research Center as part of its Pew-Templeton Global Religious Futures project, which analyzes religious change and its impact on societies around the world.
The report was based on surveys of nearly 80,000 adults during the first half of last year outside the United States and mid-2023 to mid-2024 in the U.S. While the numbers can point to global trends, they cannot provide a worldwide average because most of Africa as well as China and Russia were not surveyed.
Although what Pew refers to as “religious switching” is common, the rate varies widely from country to country. The country studied with the highest rate of switching is South Korea, where half of adults have left the religion of their childhood. However, in four countries — Indonesia, Israel, Bangladesh and Tunisia — the rate of switching is 1 percent or less.
For the United States, the rate is 28 percent. Right in the middle are Brazil, Mexico and South Africa at 21 percent.
In nearly all the countries surveyed, a strong majority of those changing religious affiliation have switched to atheism, agnosticism or no religion in particular.
The study did not make an attempt to delve into the reasons for religious disaffiliation. But in general, the rate of religious change varied little by age, gender or education level.
After South Korea, the countries with the highest rates of religious change, more than a third, were, in order, Spain, Canada, Sweden, the Netherlands, the United Kingdom, Australia, Germany, France and Japan.
Highlights
Here are some of the highlights of the report according to religious grouping:
Christianity
Christian numbers have declined most sharply in Spain, where 87 percent of the adults were raised Christian. But the the proportion of Christians has plummeted to a bare majority at 54 percent. More than a third, 36 percent, of adults have left Christianity, while 3 percent have joined.
Other countries with large declines are Sweden and the Netherlands, in which about two-third of adults were raised Christian (70 and 64 percent, respectively), but 30 percent of the population in each country have left Christianity.
In the United States, 80 percent of adults were raised Christian, but now 62 percent are.
Singapore is the country where Christianity has had proportionally the largest growth. Although a small minority, 12 percent, were raised Christian, today 18 percent are.
The country with the highest Christian retention rate is the Philippines at 99 percent.
Overall, the majority of those who have left Christianity say they no longer identify with a religion.
Buddhism
In two Asian countries, Japan and South Korea, almost half of those raised Buddhist have left the religion. Those raised Buddhist were 58 and 30 percent, respectively; now, the numbers are 34 and 17 percent, respectively.
Buddhism is most stable in Sri Lanka, were 71 percent were raised in that religion. And while there has been a slight amount of churning, with 1 percent of the population leaving the faith and 1 percent joining, the number remains at 71 percent.
The retention rate was also high in Thailand, where 90 percent were raised in Buddhism and 88 percent remain that way.
Islam
In contrast with Christianity and Islam, the number of adherents of Islam has remained extremely stable. Of the 13 countries in the survey with a significant percentage of Muslims, eight showed a statistically insignificant number (in other words, rounded to 0 percent) of people leaving the faith.
The country with the biggest Muslim losses was Turkey, but even there the change was small: While 98 percent of Turks were raised Muslim, today the figure stands at 95 percent.
Although the sample size was small in the United States, with only 1 percent of residents being raised Muslim, the proportion leaving was larger than in the other countries surveyed. Of those raised Muslim, 10 percent have left for other religions and 13 percent have left religion.
Hinduism
Of the countries studied, only four — Bangladesh, India, Sri Lanka and the United States — have enough Hindus for reliable analysis. Retention rates are high in all four countries: approaching 100 percent in India and Bangladesh, around 90 percent in Sri Lanka, and 80 percent in the U.S.
In Sri Lanka, most who have left Hinduism have converted to Christianity. In the U.S., about a third of those leaving have become Christians with most of the remainder now having no religious affiliation.
Judaism
About 80 percent of the world’s Jews live in the United States or Israel, the only two countries with sample sizes large enough to measure reliably.
In Israel, nearly everyone raised Jewish as a religious identity has remained Jewish. (The survey was designed to measure religious affiliation rather than cultural or ethnic identification.) In the United States, however, about a fourth raised with Judaism as their religion have left the faith.
In both countries, most who have left Judaism as a religion have become unaffiliated with a religion.
Atheism / agnosticism / nothing in particular
In almost every country analyzed, more people have changed their status to unaffiliated (atheist, agnostic or nothing in particular) than have switched from that category to a religion.
In most of the countries, the percentage of those unaffiliated with a religion has more than doubled from the number that were raised that way. The trend is most pronounced in Italy, where only 3 percent were raised without a religion; now that number is 23 percent.
The country with the highest rate of lack of religious affiliation is Japan, at 55 percent. The number raised that way is 31 percent.
In the United States, 13 percent say they were raised without a religion; now that number is 29 percent.
Countries involved in the study were Argentina, Bangladesh, Brazil, Canada, Chile, Colombia, France, Germany, Ghana, Greece, Hungary, India, Indonesia, Israel, Italy, Japan, Kenya, Malaysia, Mexico, the Netherlands, Nigeria, Peru, the Philippines, Poland, Singapore, South Africa, South Korea, Spain, Sri Lanka, Sweden, Thailand, Tunisia, Turkey, the United Kingdom and the United States. Countries among the 10 most populous not included were China, Pakistan and Russia.
A median is a type of average. In this study, to say that the median rate religious switching is 21 percent means that half the countries had a rate above 21 percent while the other half had rates below 21 percent. The more familiar type of average, known as the mean, was not used in this report because of differing polling methods and margins for error in the different countries.