The solubilities of 3-methylbenzoic acid in 2-methoxyethanol (ME)-water mixtures (0 to 80 mass % of ME) have been measured at 298.15 K. The thermodynamic dissociation constants (K(T)) have been determined from the solubility values in conjunction with pH measurements. The standard free energies of transfer of the substituted benzoic acid [DELTA G(t)0 (HA)] from water to the mixed solvents have also been evaluated.