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2017 Update on Americans and Religion

2017 Update on Americans and Religion

Story Highlights

  • About three-quarters of Americans identify with a Christian faith
  • 37% are highly religious; 33% not religious at all
  • 48% of those who are highly religious approve of Trump

WASHINGTON, D.C. -- The end of the calendar year provides a good time to take stock of Americans' religion, including the way in which it remains highly intertwined with politics.

Protestants continue to make up the largest religious group in America, totaling 49% of U.S. adults interviewed as part of Gallup's Daily tracking in 2017. Catholics are the next-largest group, at 23% of the population, with Mormons accounting for about 2%. This means that about three-quarters of Americans, overall, identify with a Christian faith.

Another 6% of the population identifies with a non-Christian faith, including Judaism, Islam and others, while 21% of Americans do not have a formal religious identity. All of these groups are within a percentage point of where they were in 2016, suggesting that the shifts seen in previous years have stabilized, particularly the growth among those with no religious identity.

American Religious Identification
2016 2017
% %
Protestant/Other Christian 48.9 48.5
Catholic 23.0 22.7
Mormon 1.8 1.8
Jewish 2.1 2.1
Muslim 0.8 0.8
Other non-Christian religion 2.5 2.9
No religious identity 20.8 21.3

Thirty-seven percent of Americans can be classified as highly religious based on their self-reports of church attendance and the importance of religion in their lives. This is within one percentage point of the 38% recorded last year. Another 30% of Americans are classified as moderately religious and 33% as not religious at all.

Religiosity: 2016-2017
2016 2017
% %
Highly religious 38 37
Moderately religious 30 30
Not religious 32 33

Mormons are by far the most religious of the major religious groups in the U.S., with 74% classified as highly religious. Protestants, Muslims and Catholics are more of a mix of highly and moderately religious adults, while Jews and those who identify with another non-Christian religion are the least religious.

Religiosity Within Major Religious Groups: 2017
Mormon Protestant Muslim Catholic Jewish Other non-Christian religion
% % % % % %
Highly religious 74 50 45 40 19 16
Moderately religious 16 34 37 35 31 36
Not religious 10 16 18 24 50 48
GALLUP, Jan. 2-Dec. 20

The relationship between religiosity and political party identification remained virtually the same in 2017 as in 2016. About half of Republicans are highly religious, compared with about a third of independents and Democrats. Religiosity among the latter two groups is almost identical, including 38% and 39% of independents and Democrats, respectively, who are not religious.

Religiosity Within Partisan Groups
Republicans Independents Democrats
2016 2017 2016 2017 2016 2017
% % % % % %
Highly religious 51 51 33 32 33 32
Moderately religious 29 29 30 30 30 29
Not religious 20 20 37 38 37 39

Americans who are highly religious are much more likely to approve of President Donald Trump's performance in office than are those who are moderately or not religious. These relationships are not unexpected given the correlation between religiosity and party identification. President Barack Obama had his highest approval ratings in office among those who were not religious, while George W. Bush, like Trump, had his highest approval ratings among the highly religious.

Trump Approval by Religiosity
Highly religious Moderately religious Not religious
% % %
Approve of Trump 48 40 28
Disapprove of Trump 46 54 67
GALLUP, Jan. 2-Dec. 20

The relationship between religiosity and Trump job approval is mainly among non-Hispanic white Americans. Trump's approval is 64% among highly religious whites, twice as high as it is among whites who are not religious. There is little relationship between religiosity and views of Trump among nonwhites; approval is below 20% in all three religious groups.

Trump Approval by Religiosity, Among Whites and Nonwhites: 2017
Non-Hispanic white Nonwhite
Highly religious Moderately religious Not religious Highly religious Moderately religious Not religious
% % % % % %
Approve 64 54 32 19 18 16
Disapprove 32 42 64 73 74 77
GALLUP, Jan. 2-Dec. 20

Bottom Line

The overall religious composition of the adult population in the U.S. is about the same as it was last year, with the significant majority of Americans identifying with either the Protestant or Catholic faith, along with about one in five who say they have no formal religious identity. Americans are also about as religious this year as last year, based on their self-reported church attendance and the importance of religion in their lives. Two-thirds of Americans are either highly or moderately religious.

The basic pattern of association between Republican partisan identity and higher levels of religiosity continued in 2017, with the associated finding that Trump does better among those who are highly religious than among those who are less religious. The relationship between religiosity and Trump approval is primarily found among non-Hispanic white Americans; nonwhites give Trump very low job approval ratings regardless of their religiosity.

Survey Methods

Results for this Gallup poll are based on telephone interviews conducted Jan. 2-Dec. 20, 2017, on the Gallup U.S. Daily survey, with a random sample of 126,965 adults, aged 18 and older, living in all 50 U.S. states and the District of Columbia. For results based on the total sample of national adults, the margin of sampling error is ±1 percentage point at the 95% confidence level. All reported margins of sampling error include computed design effects for weighting.

Each sample of national adults includes a minimum quota of 70% cellphone respondents and 30% landline respondents, with additional minimum quotas by time zone within region. Landline and cellular telephone numbers are selected using random-digit-dial methods.

Learn more about how the Gallup U.S. Daily works.

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