Abstract: Process for the preparation of heat-stable, antimony-free polyesters of neutral color and the products which can be prepared by this process A process for the preparation of heat-stable, antimony-free polyesters of neutral color by esterification of aromatic dicarboxylic acids or transesterification of lower aliphatic esters of aromatic dicarboxylic acids with aliphatic diols and subsequent polycondensation in which a possible transesterification is carried out in the presence of 20 to 120 ppm, based on the catalyst metal, of a transesterification catalyst, after the esterification or transesterification has ended, phosphoric acid, phosphorous acid and/or phosphonic acids or a derivative thereof are added to the esterification or transesterification batch as a completing agent in an amount which is 100% of the amount equivalent to the transesterification catalyst employed and up to 99% of the amount equivalent to the cobalt to be employed, up to 80 ppm of cobalt in the form of a cobalt compound are then adde