A general strategy for recycling polyester wastes into carboxylic acids and hydrocarbons has been developed. The method involves breaking the ester C-alkoxy-O bond in polyesters through nucleophilic substitution of halide anions in ionic liquids (ILs) under mild conditions, followed by hydrogenation over Pd/C. This process enables the degradation of various polyesters, including aromatic and aliphatic ones, copolyesters, and polyester mixtures, into corresponding carboxylic acids and alkanes. Additionally, tetrabutylphosphonium bromide can directly decompose polyesters with β-H into carboxylic acids and alkenes under hydrogen- and metal-free conditions. The hydrogen-bonding interaction between ILs and ester groups in polyesters enhances the nucleophilicity of halide anions, activating the C-alkoxy-O bond. This strategy achieves complete degradation of polyesters into carboxylic acids with high atomic economy and simplifies product separation by producing hydrocarbons. The method is applicable for recycling various polyesters, including PET, PLA, PHB, and others, into valuable chemicals. The study demonstrates a promising approach for sustainable polyester recycling, contributing to a circular economy by converting plastic waste into useful chemicals. The process is efficient, environmentally friendly, and suitable for industrial applications.A general strategy for recycling polyester wastes into carboxylic acids and hydrocarbons has been developed. The method involves breaking the ester C-alkoxy-O bond in polyesters through nucleophilic substitution of halide anions in ionic liquids (ILs) under mild conditions, followed by hydrogenation over Pd/C. This process enables the degradation of various polyesters, including aromatic and aliphatic ones, copolyesters, and polyester mixtures, into corresponding carboxylic acids and alkanes. Additionally, tetrabutylphosphonium bromide can directly decompose polyesters with β-H into carboxylic acids and alkenes under hydrogen- and metal-free conditions. The hydrogen-bonding interaction between ILs and ester groups in polyesters enhances the nucleophilicity of halide anions, activating the C-alkoxy-O bond. This strategy achieves complete degradation of polyesters into carboxylic acids with high atomic economy and simplifies product separation by producing hydrocarbons. The method is applicable for recycling various polyesters, including PET, PLA, PHB, and others, into valuable chemicals. The study demonstrates a promising approach for sustainable polyester recycling, contributing to a circular economy by converting plastic waste into useful chemicals. The process is efficient, environmentally friendly, and suitable for industrial applications.