Bailey hurt his right elbow and went on the 15-day disabled list Aug. 16. The Reds initially expected to have him back in September.
The Reds were off on Monday before opening a three-game series in Baltimore. They plan to call up 10 players before the game, including right-handed reliever J.J. Hoover.
They also expect to add right-hander Carlos Contreras, right-hander Daniel Corcino, infielder Jake Elmore, left-hander David Holmberg, catcher Tucker Barnhart, first baseman Donald Lutz, outfielder Yorman Rodriguez, outfielder Jason Bourgeois and left-hander Ryan Dennick.