A two-dimensional finite element (FE) model was developed and nonlinear FE analyses were carried out, using the ANSYS software, to predict the buckling, postbuckling and initial failure loads of pultruded glass reinforced plastic (GRP) wide flange (WF) columns. Phenomenological failure criteria were proposed to predict failure initiation at the web-flange junctions of pultruded GRP WF columns, whereas the Tsai–Wu failure criterion was used for the web and flanges. Initial failure analysis was carried out with reasonable success as a post-processing operation on the nonlinear analysis results. The numerical predictions of the buckling, postbuckling and initial failure loads of pultruded GRP WF columns were in reasonably good agreement with the experimental results