A process for the production of carboxylic esters by reaction of at least one carboxylic acid and/or at least one carboxylic anhydride, selected from aromatic mono-, di-, tri-, or tetracarboxylic acids, aliphatic mono- and dicarboxylic acids, hydroxycarboxylic acids, alicyclic mono-, di-, tri-, and tetracarboxylic acids, heterocyclic dicarboxylic acids, the anhydrides of the abovementioned carboxylic acids, and mixtures thereof, and at least one alcohol R 1 -OH, in which R 1 is selected among unbranched and branched saturated C 5 -C 13 -alkyl moieties, with the proviso that the reaction takes place - in the presence of at least one ionic liquid which is selected from among salts of the general formula (Ia), in which radicals R 2 and R 3, independently of one another, are hydrogen, unsubstituted C 1 -C 6 -alkyl, unsubstituted C 2 -C 6 -alkenyl, unsubstituted C 5 -C 6 -cycloalkyl, C 6 -C 10 -aryl or heteroaryl having 5 to 6 ring atoms, it also being possible for the 2 last-mentioned radicals to have 1, 2 or 3 substituents selected from C 1 -C 6 -alkyl, C 1 -C 6 -alkoxy or halogen, radicals R 4, R 5, and R 6, independently of one another, are hydrogen, unsubstituted C 1 -C 6 -alkyl, unsubstituted C 5 -C 6 -cycloalkyl or benzyl, it also being possible for benzyl to have 1, 2 or 3 substituents selected from C 1 -C 6 -alkyl, C 1 -C 6 -alkoxy or halogen, and R c is unsubstituted C 1 -C 6 -alkyl, unsubstituted C 5 -C 6 -cycloalkyl or aryl, where aryl may be substituted by 1, 2 or 3 C 1 -C 6 -alkyl radicals, - in the presence of at least one catalyst selected among organic sulfonic acids, and - with distillative removal, in the form of an azeotropic mixture with the alcohol R 1 -OH used, of at least one portion of the water formed during the reaction, where at least to some extent the alcohol R 1 -OH removed by distillation is returned to the reaction system. - in the presence of at least one ionic liquid which is selected from among salts of the general formula (Ia), in which radicals R 2 and R 3, independently of one another, are hydrogen, unsubstituted C 1 -C 6 -alkyl, unsubstituted C 2 -C 6 -alkenyl, unsubstituted C 5 -C 6 -cycloalkyl, C 6 -C 10 -aryl or heteroaryl having 5 to 6 ring atoms, it also being possible for the 2 last-mentioned radicals to have 1, 2 or 3 substituents selected from C 1 -C 6 -alkyl, C 1 -C 6 -alkoxy or halogen, radicals R 4, R 5, and R 6, independently of one another, are hydrogen, unsubstituted C 1 -C 6 -alkyl, unsubstituted C 5 -C 6 -cycloalkyl or benzyl, it also being possible for benzyl to have 1, 2 or 3 substituents selected from C 1 -C 6 -alkyl, C 1 -C 6 -alkoxy or halogen, and R c is unsubstituted C 1 -C 6 -alkyl, unsubstituted C 5 -C 6 -cycloalkyl or aryl, where aryl may be substituted by 1, 2 or 3 C 1 -C 6 -alkyl radicals, - in the presence of at least one catalyst selected among organic sulfonic acids, and - with distillative removal, in the form of an azeotropic mixture with the alcohol R 1 -OH used, of at least one portion of the water formed during the reaction, where at least to some extent the alcohol R 1 -OH removed by distillation is returned to the reaction system. radicals R 2 and R 3, independently of one another, are hydrogen, unsubstituted C 1 -C 6 -alkyl, unsubstituted C 2 -C 6 -alkenyl, unsubstituted C 5 -C 6 -cycloalkyl, C 6 -C 10 -aryl or heteroaryl having 5 to 6 ring atoms, it also being possible for the 2 last-mentioned radicals to have 1, 2 or 3 substituents selected from C 1 -C 6 -alkyl, C 1 -C 6 -alkoxy or halogen, radicals R 4, R 5, and R 6, independently of one another, are hydrogen, unsubstituted C 1 -C 6 -alkyl, unsubstituted C 5 -C 6 -cycloalkyl or benzyl, it also being possible for benzyl to have 1, 2 or 3 substituents selected from C 1 -C 6 -alkyl, C 1 -C 6 -alkoxy or halogen, and R c is unsubstituted C 1 -C 6 -alkyl, unsubstituted C 5 -C 6 -cycloalkyl or aryl, where aryl may be substituted by 1, 2 or 3 C 1 -C 6 -alkyl radicals, - in the presence of at least one catalyst selected among organic sulfonic acids, and - with distillative removal, in the form of an azeotropic mixture with the alcohol R 1 -OH used, of at least one portion of the water formed during the reaction, where at least to some extent the alcohol R 1 -OH removed by distillation is returned to the reaction system. - in the presence of at least one catalyst selected among organic sulfonic acids, and - with distillative removal, in the form of an azeotropic mixture with the alcohol R 1 -OH used, of at least one portion of the water formed during the reaction,