The nonclassical symmetries method is applied to a class of reaction-diffusion equations with nonlinear source, i.e. ut=uxx+cux+R(u, x). Several cases are obtained by using suitable solutions the heir-equations as described in [M.C. Nucci, Nonclassical special heir-equations, J. Math. Anal. Appl. 279 (2003) 168–179].