The Heat announced the deal about two hours prior to Thursday's 3 p.m. ET trade deadline.
Mason will be waived by the Kings and become a free agent, and the pick the Kings are trading to the Heat likely will never convey.
The Heat were interested in having a roster spot open so they can add a free agent that may become available in the next week. They are looking for a veteran wing player.
Mason averaged 3.0 points in 25 games for the Heat this season.