Allen told the Heat on Friday night that he has decided to leave the Boston Celtics and join up with the reigning NBA champions.
Heat owner Micky Arison tweeted the news just after 9:30 p.m., and Allen’s decision was subsequently confirmed by his agent, James Tanner.
It is believed Allen accepted the Heat’s mid-level exception that starts at $3.09 million, which means he left an offer worth twice as much per year on the table from the Celtics.
Allen met with the Heat Thursday afternoon and evening in Miami.
Information from ESPN.com’s Brian Windhorst and The Associated Press was used in this report.