A method for closing foldable packages and a closing device has a first support element having a first support surface on which a bottom flap of a package can be arranged, and a second support element having a second support surface on which a top flap of the package can be arranged. A first push-in bar and a second push-in bar of the closing device are moveable along a movement path which has in some portions a component parallel to a first transverse direction in order to push the package in the first transverse direction. By doing so, the bottom flap and the top flap are folded towards a frame of the package.