Numerical computations have been made for the laminar boundary‐layer development and stability of a series of similar Falkner–Skan wedge flows in freon‐114 with surface heating. The variation in physical properties (primarily viscosity) of the fluid alters the thickness and velocity profile of the boundary layers and consequently, their stability characteristics. Heating of the surface, with an accompanying reduction of viscosity close to the wall, has the qualitative effect as a more negative (i.e., more favorable) pressure gradient. The effects of various combinations of pressure gradient and heat transfer on the characteristics of these variable‐property laminar boundary layers, on their neutral stability, and on the growth of disturbances by the linear stability theory are described. The minimum critical Reynolds number is presented as a function of pressure gradient, temperature difference, and free‐stream temperature. The latter has an appreciable effect because of the rapid change in the temperature derivative of the viscosity with temperature level.