An image forming apparatus includes plural medium transport paths that branch at a predetermined branching position and along which a medium is transported in a curved state; a switching member disposed at the branching position and including a guide surface that allows the medium to be transported along one of the medium transport paths, the switching member switching between the medium transport paths; an output unit that outputs the medium toward a stacking portion, on which the medium is to be stacked, while corrugating the medium; and a guide portion that guides the medium from the branching position toward the output unit in a region in which the medium is corrugated.