American Adults Religious Identification (Age 18+)

Christian Religious Groups  2001 2008
Catholic 24.5% 25.1%
Baptist 16.3% 15.8%
Mainline Christian
(Methodist, Lutheran, Presbyterian, Episcopalian/Anglican, United Church of Christ, etc.)
17.2% 12.9%
Generic Christian
(Christian Unspecified, Non-Denominational. Christian,
Protestant Unspecified, Evangelical/Born Again)
6.8% 5.0%
(Pentecostal Unspecified, Assemblies of God, Church of God)
3.8% 3.5%
Total Christian 76.7% 76.0%
Other Religious Groups    
Jewish 1.3% 1.2%
Muslim/Islam 0.5% 0.6%
Buddhist 0.5% 0.5%
New Religious Movements
& Other Religions
0.9% 1.2%
No Religion Groups    
Agnostic 0.5% 0.9%
Atheist 0.4% 0.7%
Not a worldview group, but rather
individuals who stated: "No religion"
13.2% 13.4%
Total No Religion Specified 14.1% 15.0%
Teaching About Religion
in support of civic pluralism
U.S. Demographics

Demographics is the study of the distribution of peoples within a geographic
setting. For this section, the setting of interest is the USA, at large.

The links below lead to U.S. maps showing the distribution of religion, state
by state. The links are in order of population size in the U.S. overall, with
Catholicism showing the largest number of adherents and Buddhism the
smallest (for which data are shown here).

The Big Picture

This table offers a glimpse of U. S. statistics for religious and nonreligious
worldviews as reported by ARIS 2001 and 2008.

State-by-State Comparisons

All data within this section comes from the 2001 study, the American
Religious Identification Survey
(ARIS), by Barry A. Kosmin, Egon Mayer,
and Ariela Keysar at the Graduate Center of the City University of New York.
ARIS 2001 makes data available for the continental U.S. and DC. If you
need additional data (such as state by state information on religions) please
refer to the study located at

How can one sensibly compare distributions of various adherent groups?
Some groups number in the millions and others in mere thousands of
members. One way to do this is through the use of demographic maps. With
the help of statistics, a map can be colored to show how representation of a
group (whether small or large) differs across the states. The ARIS study did
not include Alaska or Hawaii due to the cost of performing the study.

One useful statistical measure for demographic maps is the
quartile. This
statistical grouping bundles equal numbers of counted adherents into four
sets. Those states containing the "lowest representation" quarter of the total
adherents are in the first quartile set and shown in one color, the next batch
(continuation of higher representations forming the second quartile) are
shown in another color, and so on. For quartiles to be of use, the population
under study needs to be quite large.

A second method for demographic maps of small populations is to color the
states according the
percent of the religious population in the state. For
example the total population of a given religion might be pictured by coloring
states having 1% one color, 2% another color, and 3% and 4% other colors.

If you are unfamiliar with these two ideas, a sample case may be helpful.
Example Table and Map (Quartiles and Percent).