a method of making a packaging bag from a wrapper sheet includes the following steps : forming a continuous sleeve from the wrapper sheet ; forming a longitudinal seal inward of and adjacent to a longitudinal folded edge of the wrapper sheet by bonding overlapping longitudinal edge portions of the sleeve to one another ; forming a transverse seal bonding overlapping sheet portions to one another ; cutting a tear - open slit through at least three layers of the wrapper sheet in the transverse seal in an area of intersection with the longitudinal seal ; transversely severing the sleeve to provide a packaging bag having an open end spaced from the transverse seal ; charging the packaging bag with goods through the open end ; and forming an additional transverse seal bonding overlapping sheet portions to one another for closing the open end .