Musk had hinted about the possibility of reinstating Jones earlier.
Jone’s reinstatement may anger leftist advertisers who have left Twitter and complained about “hate speech” on the free speech platform.
Musk posted a poll on Saturday asking if Jones should be reinstated, with the results showing 70% of those who responded in favor.
Early Sunday, Musk tweeted, “The people have spoken and so it shall be.”
A few hours later, Jones’ posts were visible again and he retweeted a post about his video game.
He and his Infowars show had been “permanently” banned in 2018.
Musk, who has described himself as a free speech absolutist, said the move was about protecting those rights.
In response to a user who posted that “permanent account bans are antithetical to free speech,” Musk wrote, “I find it hard to disagree with this point.”
Restoring Jones’ account comes as Musk has seen a slew of big brands, including Disney and IBM, stop advertising on X after a report by leftist advocacy group Media Matters said ads were appearing alongside “pro-Nazi” content and “white nationalist” posts.
Musk has said advertisers are engaging in “blackmail” and, using a profanity, told them to go away.
“Don’t advertise,” Musk said in an on-stage interview late last month at The New York Times DealBook Summit.
After buying Twitter last year, Musk said he was granting “amnesty” for suspended accounts and has since reinstated President Donald Trump; Ye, the rapper formerly known as Kanye West; and Rep. Marjorie Taylor Greene.
Trump, who was banned for encouraging the Jan. 6, 2021, Capitol insurrection, has his own social media site, Truth Social, and has only tweeted once since being allowed back on Twitter.
Adapted from reporting by the Associated Press