When the U.S. Congress convened for its 119th session on Jan. 3, it had marginally fewer Christians than it did in the previous session (2023-25), continuing a gradual, 10-year decline.

Christians will make up 87 percent of voting members in the Senate and House of Representatives, combined, in the 2025-27 congressional session, according to new research done by the Pew Research Center.

That's down from 88 percent in the last session and 92 percent a decade ago.

Overall, there are 461 Christian members of Congress, compared with 469 in the previous Congress and 491 during the 2015-17 session.

It will be the lowest number of Christians since the start of the 2009-2011 congressional session, the first for which Pew Research Center conducted this analysis.1

Pew noted that its analysis does not include three vacant – or to be vacant – seats whose occupants remain unknown, including the Ohio Senate seat of Vice President-elect JD Vance.

Still, at 87 percent, Christians make up an overwhelming number of Congress members, far exceeding the Christian share of all U.S. adults, which stands at 62 percent after several decades of decline.

In 2007, 78 percent of U.S. adults were Christian, according to Pew Research Center's Religious Landscape Study from that year, and in the early 1960s, more than 90 percent of U.S. adults were Christian, according to historical Gallup polling.

The new Congress is also more religious than the general population by another related measure: Nearly 30 percent of Americans (28%) are religiously unaffiliated, meaning they are atheist or agnostic or say their religion is "nothing in particular."

But less than 1 percent of the U.S. Congress falls into this category, with three religiously unaffiliated members: incoming Reps. Yassamin Ansari of Arizona and Emily Randall of Washington, both of whom are Democrats, and incoming Rep. Abraham Hamadeh of Arizona, a Republican.

The share of the U.S. public that is religiously unaffiliated – sometimes called "nones" – has risen rapidly in recent decades (from 16 percent in 2007 to 28 percent in Pew's recent polling), the corresponding share of Congress has remained miniscule.

Before the 119th session, the only member of Congress categorized as religiously unaffiliated in Pew's analyses was Kyrsten Sinema, independent of Arizona, who served from 2013 through the Congress that is just ending. (She did not run for reelection in 2024.)

Of the 461 Christians in the 119th Congress, 295 are Protestant, a decrease of eight from the previous session.

Partial historical data suggests that Protestants had a much larger presence in Congress a few decades ago, including 398 members in 1961. But there have been fewer than 300 Protestants in six of the last nine sessions over the last decade and a half.

The new Congress also has 150 Catholics, two more than in the last session. Still, that's lower than the average number of Catholic members over the last decade and a half. From the 2009-2011 session, congressional Catholics had often numbered in the 160s.

Yet Protestants continue to make up a disproportionately high share of the 119th Congress (55 percent of members) when compared with the U.S. adult population (40 percent).

Baptists are the largest category of Protestants in the new Congress, with 75 members (14.1 percent of Congress). That's eight more Baptists than in the prior session.

The next largest Protestant groups in the new Congress are Methodists (26 members), Presbyterians (26), Episcopalians (22), and Lutherans (19).

• SHRINKING PROTESTANT GROUP

These four groups have had shrinking U.S. memberships in recent decades and now have a significantly smaller presence in Congress than they used to. For example, in the 112th Congress of 2011-13, there were 51 Methodists, 45 Presbyterians, 41 Episcopalians, and 26 Lutherans.

Of the 295 Protestants in Congress, 101 do not specify a particular denomination or denominational family, instead giving broad or vague answers such as "Protestant," "Christian," or "evangelical Protestant."

That is six fewer identifying so than in the last Congress, but the overall trend over the last decade has been for increasing numbers of U.S. representatives and senators to give such types of answers.

By comparison, only 58 members said they were "just Christians" or gave nonspecific, Protestant descriptions of their religious affiliation at the start of the 114th Congress in 2015.

Seventy-one members of Congress do not identify as Christians, including 32 who are Jewish.

Although that is one fewer Jewish member of Congress than in the last session, Jews continue to make up a higher share of Congress (6 percent) than of the overall adult population (2 percent).

There are four Muslims in the new House of Representatives – one more than in the last session – including three who won reelection in 2024 (André Carson, D-Ind., Ilhan Omar, D-Minn., and Rashida Tlaib, D-Mich.). The newest Muslim to enter the House will be Lateefah Simon, D-Calif.

There will also be four Hindus in the House – a gain of two from the previous session.