The invention relates to polycarbonate compositions and copolycarbonate compositions with improved melt stability, the preparation thereof and the use thereof for the production of mouldings and mouldings obtainable therefrom, wherein the compositions contain a polycarbonate or copolycarbonate containing bisphenol A, and at least one phosphorus compound of the formulae (1) and (2), wherein R1 and R2 independently of each other and among one another are chosen from the group which includes branched alkyl radicals, aryl radicals and substituted aryl radicals.