A method is given for calculating the phonon contribution to the electron-phonon mass enhancement, lambda . The contribution is estimated from the lattice parameter and the elastic constants using a method based on De Launay's phenomenological theory of lattice dynamics. The method is applied to ten different cubic metals; Nb, Ta, V, Mo, W, Pb, Al, Ir, Pt, and Pd. Good agreement with experiment is obtained, except in the case of Al. The results for Pt and Pd are discussed with reference to the theory of paramagnetic spin fluctuations.