The Orioles selected Tromp's contract from Triple-A Norfolk on Monday.
Tromp will be up with the Orioles for the second time this season after fellow catcher Adley Rutschman (wrist) was placed on the 10-day injured list in a corresponding move. Samuel Basallo (shoulder) is out of the lineup for Monday's series opener in Boston, making Tromp and Sam Huff the Orioles' only healthy catchers for the time being.