Stallings was reinstated from the 7-day concussion injured list Tuesday, Mike Persak of the Pittsburgh Post-Gazette reports.
The 31-year-old spent just over a week on the injured list but has been participating in baseball activities since last week. Taylor Davis was optioned to Triple-A Indianapolis to make room on the active roster, and Stallings will take over as the primary catcher for the final few games of the regular season.