OMAHA, Neb.—It was time.

Warren Buffett stunned the investing world Saturday by revealing his plans to step down as Berkshire Hathaway’s chief executive at year-end and hand the reins to handpicked successor, Greg Abel .

The 94-year-old investor closed the annual meeting of the company he built into one of the nation’s largest with the surprise announcement that he will recommend to Berkshire’s board that Abel begin the CEO job in 2026.

“The time has arrived,” he said, “where Greg should become the chief executive officer of the company at year-end.”

And with that, one of the greatest and longest-running shows in American capitalism entered its final months.

Buffett transformed Berkshire , once an ailing textile company, into a massive conglomerate and a cultural phenomenon. For decades, thousands of fans and investors have traveled to Omaha each year to attend what Buffett called Berkshire’s “Woodstock for Capitalists.” Millions more have watched from home, read his annual letters to shareholders and studied his wit and wisdom that often transcended investment advice.

Some of the shareholders lingering in the convention center after Buffett had left the stage said they recognized the gravity of his decision, and what it meant for the future of both Berkshire and the annual gathering in the company’s hometown.

“It’s shocking to hear it here in person today,” said Brandon Swensen, a shareholder from Deephaven, Minn., who has attended the annual meeting with his wife since 2008. “We would assume there will be a meeting next year, but will it ever be the same again I guess is maybe the burning question on a lot of people’s minds as we’re departing Omaha today.”

Buffett’s news began to elicit tributes from some of Wall Street’s prominent leaders.

“ Warren Buffett represents everything that is good about American capitalism and America itself—investing in the growth of our nation and its businesses with integrity, optimism, and common sense,” JPMorgan Chase’s CEO Jamie Dimon said in a statement. “I’ve learned so much from him to this very day, and I am honored to call him a friend.”

Buffett, who is also Berkshire’s chairman, said he would discuss the succession plan at the conglomerate’s board meeting Sunday and that he expected they would act on his recommendation at a subsequent meeting.

His pick for Berkshire’s next CEO wasn’t a surprise; he had revealed in 2021 that Abel, 62, would one day succeed him in the role. But not even Abel, sitting nearby on the stage of Omaha’s CHI Health Center, knew Buffett’s thinking on the timing of his succession plan before he revealed it in the closing minutes of the annual meeting’s question-and-answer session.

The cavernous arena was nearly silent as the legendary investor spoke. And when he finished, throngs of shareholders and fans—including Abel—stood and applauded.

Among Berkshire directors, Buffett said only his son Howard Buffett and his daughter Susan Buffett knew in advance of his plans to step down this December. He has said previously that Howard Buffett will eventually follow him as the company’s chairman , though without an executive role.

The next time Berkshire shareholders convened in Omaha for the annual meeting, though, Buffett would no longer be in charge.

“It was for me a special moment, the end of an era,” said José Luis Flores, a shareholder from the Bay Area in California.

Buffett said he doesn’t plan to disappear from the scene at Berkshire, but that under his plan Abel would have the final say at the company.

“I would still hang around and could conceivably be useful in a few cases,” he said. “But the final word would be what Greg said, in operations, in capital deployment, whatever it might be.”

Born and raised in the Canadian Prairies, Abel first entered Buffett’s orbit in 1999 when Berkshire invested in MidAmerican Energy, a Des Moines utility. Abel, along with his former boss, David Sokol , helped build out what would become Berkshire Hathaway Energy through a series of acquisitions. Buffett promoted Abel in 2018, putting him in charge of all of Berkshire’s noninsurance operations and naming him a vice chairman and a board member.

By 2021, Buffett had landed on Abel as his choice to succeed him as CEO. “Greg will be more successful than I have been, and if I said otherwise, my nose would grow,” Buffett said in December 2023.

Buffett’s long run at Berkshire began in 1965, when the stock picker took over an ailing textile company. He transformed it into an investment vehicle and, ultimately, a massive conglomerate whose businesses range from insurance and energy to railroads, footwear and candy.

Hours before his stunning announcement, as Buffett settled into his chair for the hourslong question session, he appeared to tip his hand, ever so slightly, at what was to come.

“This is my 60th annual meeting, and it’s the biggest and, I think, the best yet,” Buffett began.

Write to Karen Langley at karen.langley@wsj.com