All three players are now signed through the 2020-21 season. Fultz's option was for $12.3 million.
"Mo [Bamba], Markelle [Fultz] and Jonathan [Isaac] have each demonstrated a strong work ethic while exhibiting a commitment to team values," Magic president of basketball operations Jeff Weltman said in a statement. "We look forward to exciting futures with them as part of the Magic family."
Fultz, the No. 1 overall pick of the 2017 draft, appeared in 19 games for the Philadelphia 76ers last season, averaging 8.2 points, 3.1 assists and 3.7 rebounds. Due to a shoulder injury, he didn't play for the Magic after Orlando acquired him in a trade in February. He has played in just 33 games over his first two seasons in the NBA.
Bamba appeared in 47 games as a rookie, averaging 6.2 points, 5 rebounds and 1.4 blocks in 16 minutes per game. Isaac appeared in 75 games last season, averaging 9.6 points, 5.5 rebounds, 1.1 assists and 1.3 blocks in 27 minutes per game.