The percent beta‐ray transmission by thin Nylon and Formvar films (windows) was studied to obtain experimental ``absorption'' corrections to be used with G‐M counters employing such thin windows. It was found that window ``absorption'' included (1) energy loss of electrons traversing the films and (2) scattering of incident electrons by the film (a geometry effect). The results are plotted in several ways to exhibit the various factors involved and to permit easy use in applying the corrections. It was found that scattering of transmitted electrons was a factor of considerable importance, whereas the energy lost in traversing the film was not very important for the range investigated. The electron energy range investigated was limited to the region in which the ``absorption'' correction was considerable for the window thicknesses used. A scintillation counter was used as the detector, and the source of monoenergetic electrons was an electron gun with electrostatic focusing.