The growth of the “nones” may have decelerated but has not stopped, according to a new study by Public Religion Research Institute.
While the share of religiously unaffiliated in the U.S. has been widely reported to have plateaued, the PRRI Census of American Religion found their share actually grew from 27.4% in 2023 to a new peak of 28.1% last year.
“What we can say with more certainty is that the growth of the religiously unaffiliated is slowing down,” PRRI CEO Melissa Deckman explained about the newly released study.
But she acknowledged the rise was much slighter than the nearly 10% increase in “nones” from 2006 through the early stages of the COVID-19 pandemic.
“Whether we see continued slow, yet steady, growth in American nones, or whether their numbers plateau, will be something we monitor closely in the future,” she said.
Young people continue to dominate the ranks of the religiously unaffiliated. PRRI found 38% of Americans ages 18 to 29 identify as “nones,” compared to 34% of those 30 to 49, 22% of those 50 to 64 and 18% of those 65 and older.
“Notably, the decline in religious affiliation among the youngest Americans is largely a function of young women leaving religion,” Deckman said.
Although the proportion of religiously unaffiliated men ages 18 to 29 has remained roughly steady since 2013 at 35%, the share among women in that age group has increased from 29% in 2013 to 40% in 2024.
Overall, the survey of 40,000 Americans reported incremental changes occurring not only among “nones,” but also with those who continue to claim religious affiliation, PRRI reported.
In 2024, about 65% of U.S. adults identified themselves as Christian, including 40% identifying as white Christians and 25% as Christians of color. It was a close match to 2023 when the 66% of Americans claiming Christian faith included 41% who identified as white Christians and 25% as Christians of color.
“In 2008, when Barack Obama was elected president, about 54% of Americans identified as white and Christian,” Deckman explained. “Much like the story with the religiously unaffiliated, the declines in the three major groups of white Christians — evangelical Protestants, Mainline or non-evangelical Protestants, and Catholics — have slowed over the past few years.”
According to the survey, 13% of respondents last year identified as white evangelicals or as white Mainline Protestants/nonevangelicals. By comparison, close to 21% self-reported as white evangelicals and 17.5% as white Mainliners in 2008.
The share who identified as white Catholic also stood at 13% in 2024, when 4% identified as Black Protestants and 7% as either Hispanic or other Protestants of color. Jewish, Muslim, Orthodox Christian and Latter-day Saints were among the groups representing low single-digit shares of the U.S. population.
But PRRI reported significant differences in religious affiliation when the data is examined by political party.
“Although the religious breakdown of the major parties has not shifted significantly in the past year, there have been considerable changes since 2013,” the report states. “Overall, Christian identity has declined significantly among both Republicans and Democrats.”
The share of Democratic Christians slid from 70% in 2013 to 58% in 2024, with whites leading the decrease from 34% to 23% over the same period. The proportion of Democrats who identify as Christians of color remained relatively unchanged, from 36% to 35%. As a group, Democrats have become much more likely to identify as religiously unaffiliated, increasing from 22% just over a decade ago to 34% last year.
“In contrast, the percentage of Republicans who are Christian slightly declined by 2 percentage points since 2013, from 86% to 84%, with a 7-percentage-point decline in white Christian Republicans (75% to 68%),” the report says.
Republicans who are Christians of color, however, increased from 11% to 16%, while members of the party who identify as “nones” has increased from 10% to 12% from 2013 to 2024.
By factoring in age with partisanship, the PRRI study also showed how the bases of the Democratic and Republican parties “could not be more different,” Deckman observed.
Most Democrats identified as Christians of color (35%) followed by “nones” (34%). Another 19% checked in as white Mainline Protestants or white Catholics. Only 3% were white evangelicals.
Among Republicans, white evangelicals were the single biggest block with 29%, followed by 19% who identified as Mainline Protestants, 17% as white Catholics and 16% as Christians of color. “Nones” made up 12% of the party’s membership.
“The religious and racial makeup of the GOP is firmly grounded demographically among the oldest American cohort, while the Democratic base looks more like the religion and racial makeup of the youngest group of Americans,” Deckman said. “While we can’t assume demography is destiny for the Democratic Party, the above chart clearly demonstrates the challenges the GOP faces in expanding its base support of voters.”
The study’s look into the religious leanings of LGBTQ Americans found them to be another group becoming less religiously affiliated, with 46% who identified as “nones” in 2016 versus 54% in 2024.
“Straight Americans are significantly more likely than LGBTQ Americans to identify as white Christian (43% vs. 18%) or as Christians of color (26% vs. 19%). LGBTQ Americans are more than twice as likely to be religiously unaffiliated than straight Americans (54% vs. 25%),” the report explains.