A method of manufacturing a garbage bag comprises (a) extruding a tube of plastics material; (b) laying the tube flat to form front and rear panels; (c) welding the tube transversely to the direction of extrusion with a set of two straight end welds at suitably spaced locations; (d) cutting the material at an end cut between each pair of end welds, and (d) cutting the material at sinusoidal separating cut which will form an open end for for two bags between a pair of end welds and which extends generally transversely to the bag. The separating cut provides cut-outs are formed in the said open ends to leave projecting tie parts which are capable of being tied together to close the opening.
