An apparatus for unfolding a bifolded mailpiece comprises a pair of pivotable receiving walls for receiving a bifolded mailpiece, a pair of receiving wall cylinders for pivotally moving the receiving walls and a pair of spreader walls for spreading the bifolded mailpiece received between said receiving walls, the spreader walls being pivotally mounted and actuated by a pair of spreader wall cylinders, a ram being provided for moving the spreader walls along a vertical axis to cooperate with the receiving walls to unfold the mailpiece.