Arn Tellem confirmed an entry he wrote for the Huffington Post Web site, in which he said Johnson "announced his intention to re-sign with the Hawks for six more years."
Tellem wrote that Johnson chose to remain in Atlanta over Chicago and New York, where he would have been reunited with Mike D'Antoni, his former coach in Phoenix.
The Hawks could pay him nearly $120 million, while other teams could only give Johnson five years and pay him about $25 million less.
That made it easy to stick with the Hawks, who have reached the second round of the playoffs the past two years with Johnson as their top player. He's a four-time All-Star and has averaged more than 20 points in each of his five years with Hawks.
"His priorities are his family, his friends and his game," Tellem wrote. "Joe could have forced a sign-and-trade deal for five years with another team, but he decided that winning in Atlanta would be more meaningful. When the Hawks offered the maximum -- six years -- he happily reciprocated."
The Hawks would not comment, citing the NBA's moratorium on signings. Deals can't become official until July 8.
Johnson has been at the center of the Hawks' resurgence since arriving in Atlanta from Phoenix in a sign-and-trade deal on Aug. 19, 2005.
A 13-win team the season before he arrived, the Hawks doubled that the next season and went 53-29 in 2009-10 before getting swept by Orlando in the Eastern Conference semifinals.
Johnson averaged 21.3 points during the regular season but played poorly during that series, creating speculation he may have cost himself max dollars.
And there was thought he might want out of Atlanta, anyway, since he turned down a $60 million extension last summer and was critical of the team's fans this season.
Instead, Tellem said Johnson was impressed by the commitment of Hawks ownership and new coach Larry Drew, and said Johnson is equally committed to the team and its players.
"For his next act, Joe plans to actively recruit other top free agents to Atlanta, a place not unlike his hometown, where he feels comfortable and appreciated," Tellem wrote.
Johnson, a first-round pick of Boston in the 2001 draft, has averaged 17.6 points for his career.