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The impact fracture behavior of two common high‐density polyethylene grades for container applications were intensively studied by the instrumented Charpy impact test after well‐defined exposure to UV‐irradiation. Individual stages of the impact event, such as crack initiation and crack propagation energy as well as maximum impact load, were investigated from the recorded load–deflection curves. UV‐induced material property changes were further investigated by infrared spectroscopy, differential scanning calorimetry, and dynamic‐mechanical analysis as well as density measurements. Based on the results of the Charpy impact test, three indicators were identified to describe the extend of photooxidation on high‐density polyethylene: (a) a reduced Charpy impact strength—at least to half of its initial value for a distinctly brittle impact fracture, (b) a marked decrease in the crack propagation contribution to the impact strength, and (c) an increase of the brittle features of the fracture surface.