Terms were not discussed, but Spoelstra was believed to be entering the final year of a contract.
"We have one of the great young coaches in the league," Riley said Friday about Spoelstra, who is entering his fourth season as Heat coach. "He's an absolute member of this family and has been for a long time. We wanted to extend him and keep him in the family and not have someone steal him away from us."
Speculation surrounding Spoelstra's job was rampant early last season when the Heat struggled. However, the team won the Southeast Division with a record of 58-24 and raced through the Eastern Conference playoffs before losing to Dallas in the NBA Finals.
Spoelstra, hand picked by Riley to be his successor, has a record of 148-98 in his three seasons. He first joined the Heat in 1995 as the team's video coordinator. After two years, he was named assistant coach/video coordinator, then was promoted to assistant coach/advance scout in 1999, before becoming the assistant coach/director of scouting in 2001.