Relationships defining the ductility capacity of rectangular unconfined masonry shear walls are developed. The limit to ductility is imposed by an ultimate strain of 0.0025 and the shape of a recently proposed stress-strain curve for unconfined masonry, Results are presented in the form of simple charts, suitable for design use, giving displacement ductility capacity in terms of material strengths, reinforcement ratios, axial load and aspect ratio. Options open to the designer when the charts indicate insufficient ductility is available for the design seismic base shear are discussed. A method for extending the applicability of the charts to non-rectangular sections is suggested.