John Stewart Hagestad III (born April 10, 1991) is an American amateur golfer.

[2] Hagestad won the 2016 U.S. Mid-Amateur at Stonewall, in Elverson, Pennsylvania, earning a spot at the 2017 Masters Tournament.

[3] He became the first U.S. Mid-Amateur champion qualifier to make the cut at the Masters (Jay Sigel was 1987 Mid-Amateur champion and made the cut at the 1988 Masters Tournament, but at the time the Mid-Amateur champion did not receive an invite and Sigel qualified by playing for the United States in the Walker Cup).

[4][5] Hagestad finished in a tie for 36th place, and won the Silver Cup as the lowest-scoring amateur.

[8][9] Hagestad teamed with Emilia Migliaccio, Brandon Wu, and Rose Zhang to win the mixed team gold medal at the 2019 Pan American Games.