AbstractTransverse stiffeners are used in slender steel plate girders along the span to give web lateral support and increase plate girder shear resistance. According to several studies, transverse stiffeners are primarily engaged in out‐of‐plane bending to laterally limit the edges of the panel as it buckles, rather than axial compression to anchor the tension field. As a result, the axial loading defined in EN 1993‐1‐5 [1] for the design of transverse stiffeners, based on tension field action, is usually deemed to be substantially larger than that observed in laboratory testing and numerical simulations. The test results of six plate girders loaded to failure, with slender webs and two transverse stiffener geometries, are presented. FE‐models that accurately replicate the tests provide a thorough view of the plate girder behaviour. The stiffeners internal forces are evaluated during plate girder loading up to failure. The transverse stiffener internal forces attained by both models are compared. It is confirmed that both the axial compression and the bending moment in the intermediate transverse stiffeners are much lower than the values prescribed by the EN 1993‐1‐5 [1].