The influence of temperature and thickness on the electrical resistivity and Seebeck coefficient of polycrystalline SnTe thin films was investigated in detail. The size effect data for the electrical resistivity and Seebeck coefficient fit very well with Tellier's effective mean free path model. Different physical parameters such as Fermi energy (EF) and effective mass (m*) were evaluated. From this it is concluded that heavy holes are the dominant charge carriers. The Seebeck coefficient data were also fitted into the Jain-Verma expression to evaluate the scattering parameter (b) and the value of b clearly indicates the dominance of lattice scattering in SnTe. © 1988 IOP Publishing Ltd.