The invention refers to a device (1) and method for sterilizing partly formed packages (6) in a packaging machine. The device (1) comprises an inner chamber (2) and an outer chamber (3), the inner chamber (2) being provided with a sterilization unit (5). Further, it comprises a carrier unit (10), comprising a separating member (11) and a package carrying member (12), which is being adapted to rotate between a first position in which the package carrying member (12) is located in the outer chamber (3), and in which the separating member (11) separates the inner chamber (2) from the outer chamber (3), and a second position in which the carrier unit (10) has rotated a package (6) into the inner chamber (2) and in which the separating member (11) separates the inner chamber (2) from the outer chamber (3).