Superconducting indium films are studied to determine the effect of film thickness on transition temperature in the range of thicknesses from about 100 to about 1000 A. Films of varying thicknesses are produced by vacuum deposition ontoz‐cut quartz substrates. To ensure reproducibility, films are produced in groups of five. Comparisons are made with the theoretical models of Toxen and Stronginet al., and the effect of electron mean free path is calculated in an approximate manner. In addition, an effective electron‐phonon coupling constant is obtained for the surface‐layer model.