The Southern Baptist Convention says it lost more than 200,000 members last year.
It was the ninth consecutive year of decline for the nation's largest protestant denomination.
Their membership now stands at 15.3, according to the latest statistics compiled by LifeWay Christian Resources.
Hartford Seminary sociologist of religion Scott Thumma suggested a growing preference for nondenominational congregations may be one reason for the decline in membership.
"Nondenominational churches have most of the same characteristics in terms of theology and worship style as SBC churches but without the denominational baggage of its reputation or pronouncements," he told the Religion News Service.
Meanwhile, SBC Executive Committee President Frank Page didn't put a positive spin on the numbers.
"God help us all!" he said in a news release. "In a world that is desperate for the message of Christ, we continue to be less diligent in sharing the good news."