The evaluation of the hydrated chloride anion polarizability is hereby addressed by using density functional theory based calculations in the condensed phase. In this study, the quantum probability associated with maximally localized Wannier functions is included to account for the spatial extent of the electronic density. It is shown that the anion polarizability is not appreciably influenced upon solvation. The method could be applied to systems where the quantum state is separable; issues related to system size dependence and about its applicability to other systems are discussed.