The extrusion of polymer compositions based on polyvinyl chloride (PVC) and in particular to a method in which polymer compositions are produced that have an elongation at break of at least 200%, a tensile strength of at least 10 N/mm2 with a specific energy input SEI of 0.03 to 0.20 kWh/kg and in particular 0.04 to 0.16 kWh/kg. The method is expediently carried out such that a plasticiser is added in a plurality of portions to the non-composed polyvinyl chloride and mixed into said polyvinyl chloride. The method thereby offers a fast and simple possibility of producing products from finished soft PVC, the production of said products requiring only a single processing device in the form of an extruder.