The 28-year-old left-hander landed on the IL on May 10 with inflammation in his pitching elbow.
Prior to the injury, Alvarado had posted a 0.63 ERA with five saves in 14 appearances. He has struck out 24 batters and walked none in 14⅓ innings.
The Phillies optioned right-hander Connor Brogdon to Triple-A Lehigh Valley to make room on the roster. Brogdon, 28, is 2-1 with a 4.03 ERA in 27 appearances this season. He has 26 strikeouts in 29 innings.
Jose Alvarado rejoins Phillies bullpen after IL stint