This study presents a novel and general strategy for recycling polyester wastes into carboxylic acids and hydrocarbons. The approach involves breaking the C_alkoxy-O bond in polyesters through nucleophilic substitution of halide anions from ionic liquids (ILs) under mild conditions. When combined with hydrogenation over Pd/C, the method can deconstruct various polyesters, including aromatic and aliphatic ones, copolyesters, and polyester mixtures, into corresponding carboxylic acids and alkanes. Additionally, ILs with halide anions can directly decompose polyesters with β-H bonds into carboxylic acids and alkenes under metal-free conditions. The hydrogen-bonding interaction between the IL and the ester group in polyester enhances the nucleophilicity of the halide anion, activating the C_alkoxy-O bond. This strategy not only provides a viable feedstock for the production of valuable chemicals but also simplifies the separation of products, making it a promising approach for the circular economy in plastic waste management.This study presents a novel and general strategy for recycling polyester wastes into carboxylic acids and hydrocarbons. The approach involves breaking the C_alkoxy-O bond in polyesters through nucleophilic substitution of halide anions from ionic liquids (ILs) under mild conditions. When combined with hydrogenation over Pd/C, the method can deconstruct various polyesters, including aromatic and aliphatic ones, copolyesters, and polyester mixtures, into corresponding carboxylic acids and alkanes. Additionally, ILs with halide anions can directly decompose polyesters with β-H bonds into carboxylic acids and alkenes under metal-free conditions. The hydrogen-bonding interaction between the IL and the ester group in polyester enhances the nucleophilicity of the halide anion, activating the C_alkoxy-O bond. This strategy not only provides a viable feedstock for the production of valuable chemicals but also simplifies the separation of products, making it a promising approach for the circular economy in plastic waste management.