An apparatus for forming a flexible package can include a forming box having a first, second, and third portions that cooperate to define first, second, third, and fourth walls of the forming box, and one or more forming box actuators operatively coupled to the forming box to actuate the forming box between a first position for receiving a package, a second position for retaining a package, and a third position for releasing the package. The apparatus can also include a first flap folding bar disposed upstream and adjacent a first end of the forming box, and one or more first flap folding bar actuators operatively coupled to the first flap folding bar to actuate the first flap folding bar in a direction substantially transverse to a transport path of a flexible material.