Religion accounts for the largest share of the approximately US$425 billion Americans give away every year.

Even so, the charitable dollars channeled to churches and other houses of worship have slowly declined as a percentage of overall giving for decades. In 2018, the actual total both fell by 3.9% when adjusted for inflation and dipped for the first time below 30% of total giving.

I study trends in religious giving and their implications. To me, what stands out today is how well congregations are generally faring even as the share of Americans who belong to a house of worship declines.

Empty pews

The bulk of religious giving goes directly to the over 350,000 congregations nationwide dotting almost every local community. On top of churches and other houses of worship, religious giving covers donations made directly to religious denominations, missionary societies and religious media.

An important trend is that the share of Americans who claim no religious affiliation is growing, having risen to 26% from 16% in 2007.

Only half of all Americans now claim to belong to a specific congregation, a historic low. And only about 45% of Americans say they go to church at least once a month, down from 54% in 2007.

Since religious affiliation and attendance at religious services are two of the leading predictors for both religious and overall charitable giving, I don’t find it surprising to see religious giving lose some ground.

Other faith-based giving

Money that donors give to clearly religious causes, including Catholic schools, Jewish community centers or Muslim relief agencies, isn’t classified as religious giving. Rather, it gets lumped with organizations focused on particular shared causes such as education or social services.

Major nonprofits with religious missions, such as the Salvation Army, World Vision and Catholic Charities, are not, in terms of the charitable statistics collected, defined as religious.

Even so, by my count, six of the nation’s 25 largest privately supported charities are clearly faith-based organizations.

Based on data collected in 2012, the most recent available, donors label three-quarters of what they give to charity as supporting religious institutions of some kind.

Relative stability

U.S. congregations are nonprofits. But unlike most other nonprofits, they generally don’t need to file paperwork with the Internal Revenue Service to report the amount of funding they receive and spend.

That makes it hard to find detailed and accurate data on congregational finances, so my colleagues and I conducted a study to get a clearer picture.

We found that religious affiliation and attendance trends do not always simply predict similar trends within congregations. About as many houses of worship are gaining congregants as losing them, with 39% growing between 2014 and 2017 and another 38% seeing their congregations shrink. The rest were stable.

The picture is similar when it comes to the amount of revenue congregations received. More congregations are bringing in more money than are bringing in less.

Catholics face more trouble

To get a clear picture, it’s important to recognize that religious participation and giving trends are not the same across the great diversity of U.S. congregations. These patterns differ overall by religious tradition and dominant race or ethnicity, along with the size, age and location of congregations.

For example, 56% of the country’s Catholic parishes received less revenue in 2017 than in 2014. But 59% of black Protestant congregations received more.

Lake Institute on Faith & Giving postdoctoral researcher Christopher Walter Munn contributed to this article.

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Lake Institute received a grant from the Lilly Endowment, Inc. (David King serving as Co-PI) to conduct the National Study of Congregations' Economic Practices.