Irreligion in the United States

In the United States, between 6% and 11% of the population demonstrated nonreligious attitudes and naturalistic worldviews, namely atheists or agnostics.^{: 1 : 18} 24% of people who do not believe in God or a universal spirit call themselves atheists. Other given answers are: "Nothing in particular", "Agnostics", "Christians", "Jewish", "Buddhists", "Other religions" and "Don't know/Refused". Atheists are between 4% and 7% of American adults.^: 18 Agnostics make up between 4 and 5% of the adult population.^: 18

A growing proportion of people appear to be reporting no religious affiliation on surveys. The percentage of Americans without religious affiliation, often labeled as "Nones", is between 22 and 31%.^: 18 "No answer" is between 2 and 3%. According to Gallup, the "None" answer to "religious preference" has grown from 2% in 1948 to 22% in 2023. "Other" and "No answer" have been somewhat stable. According to Pew, all three subgroups that together make up the religious "nones" have grown over time: in 2021, atheists were 4% (up from 2% in 2011), 5% agnostics (3% a decade before) and 20% "nothing in particular" (14% ten years before).^: 3 In 2023, atheists are still 4%. However, an Interdisciplinary Journal of Research on Religion article says atheists were already about 4% around 2008 and that had been the case since at least the 1940s.^: 8 Most of the increase in the unaffiliated comes from people who had weak or no commitment to religion in the first place, not from people who had a religious commitment. The decrease in strong belief was slower. Still, "Nones" is an unclear category. It is a heterogenous group of the not religious and intermittently religious.

For Robert C. Fuller, there are three types of unchurched: some who aren’t religious at all ("secular humanists"), those whose relationships with organized religion are ambiguous and those who are religious but unaffiliated with a church.^: 2-4 Researchers argue that most of the "Nones" should be considered "unchurched", rather than objectively nonreligious; especially since most "Nones" do hold some religious-spiritual beliefs and a notable amount participate in such behaviors. For example, 72% of American "Nones" believe in God or a higher power and a majority believe in spiritual forces beyond the natural world, and the existence of souls. Even 23% of self-identified atheists believe in a higher power, but not a god as described in the bible. The majority of the "Nones" are not nonbelievers. The "None" response is more of an indicator for lacking affiliation than an active measure for irreligiosity, and a majority of the "Nones" can either be conventionally religious or "spiritual". Americans may be becoming more "spiritual" and less "religious".^: 4 Some do appear to be spiritual but not religious.^: 5 Their numbers may be growing.^: 5

Social scientists observe that nonreligious Americans are characterized by indifference. Very few incorporate active irreligion as part of their identity, and only about 1-2% join groups promoting such values.