Graham passed away at his home in Montreat, North Carolina, spokesman Jeremy Blume said.
The skinny preacher with the booming voice evangelized to nearly 215 million people over six decades and prayed with US presidents from Harry Truman to Barack Obama.
Several presidents, including Lyndon Johnson, George W. Bush and Bill Clinton, relied closely on his spiritual counsel.
He was tall and handsome, with a disarming aw-shucks demeanor and a Southern twang to his voice. But Graham’s influence, historians say, was monumental. Some called him “America’s pastor,” others referred to him as the “Protestant pope.”
Graham is reported to have persuaded more than 3 million people to commit their lives to Christianity and his preaching was heard in 185 of the world’s 195 countries, according to the Billy Graham Evangelistic Association.
“He was probably the dominant religious leader of his era; no more than one or two popes, perhaps one or two other people, could come close to what he achieved,” said William Martin, a former historian at Rice University and the author of “A Prophet with Honor: The Billy Graham Story.”
People across the world mourned Graham’s death.
President Donald Trump said in a tweet that “the GREAT Billy Graham is dead. There was nobody like him! He will be missed by Christians and all religions. A very special man.”
Vice President Mike Pence said in a statement that “Karen and I were saddened to learn of the passing of one of the greatest Americans of the 20th century, Reverend Billy Graham.”
“We send our deepest condolences to the Graham family. Billy Graham’s ministry for the gospel of Jesus Christ and his matchless voice changed the lives of millions. We mourn his passing but I know with absolute certainty that today he heard those words, ‘Well done, good and faithful servant.’ Thank you Billy Graham. God bless you.”
Former President Jimmy Carter said in a statement that he and his wife Rosalynn “are deeply saddened” at the news of Graham’s death and that he was “pleased to count Reverend Graham” as a friend and adviser.
“Tirelessly spreading a message of fellowship and hope, he shaped the spiritual lives of tens of millions of people worldwide,” Carter said in a statement. “Broad-minded, forgiving, and humble in his treatment of others, he exemplified the life of Jesus Christ by constantly reaching out for opportunities to serve. He had an enormous influence on my own spiritual life.”
Russell Moore, the president of the Ethics & Religious Liberty Commission of the Southern Baptist Convention, said on Twitter that Graham was “the most important evangelist since the Apostle Paul.”
“He preached Christ, not himself, not politics, not prosperity,” Moore said, adding that Graham also “carried unimpeachable personal integrity.”
“RIP Billy Graham, a good and faithful servant. He fought the good fight, finished the race, and kept the faith,” US Rep. Ron DeSantis, who represents Florida’s 6th District, said on Twitter.
Televangelist Joel Osteen told CNN that Graham was his hero, and said the best way to honor him is for Christians to continue what he started.
“Preaching good news and letting people know about Christ and the love and respect that we can show one another. I think it’s to continue on in that passion. He took great steps of faith. He paved the way for young ministers like myself.”
Read More about the life of Billy Graham on CNN.com