Abstract: A method for producing filaments from polyester waste, having the steps of mechanically comminuting the polyester waste, post-condensing the comminuted polyester waste in the solid phase, melting the post-condensed polyester waste and extruding the melt in order to form filaments. Prior to carrying out the melting step for extrusion purposes, the method is completely carried out below the melting temperature of the polyester waste. The solution viscosity of the post-condensed polyester waste equals at least 1.7. Possible applications of the filaments according to the invention are, for example, reinforcement carcasses for vehicle tyres.