AbstractIn the case of two adjacent large web openings, the beam may fail by the plastification or the buckling of the intermediate web part known as the web‐post failure. Various analytical approaches have been developed to define the failure load of the intermediate web‐post which can be a key point in the design of beams with web openings. The authors led numerical studies on rectangular openings. Those studies allowed to observe that in a majority of cases, the web‐post reaches a total plastic strength. Furthermore, it allowed to observe that the loss of the web‐post did not lead to the beam failure. The beams generally failed by the formation of a Vierendeel mechanism of an enlarged or elongated opening. As a consequence, the authors propose an alternative approach for the definition of the web‐post buckling strength, considering the web‐post failure load based on lateral buckling failure and on the additional strength provided by the formation of a plastic mechanism.