The effect of notch angle and depth on the tensile properties of a peak-aged commercial 7075 alloy has been investgated. Although there seems to be little or no effect of the specimen geometry on toughness, there is a notch effect on tensile properties and this is more pronounced when the notch depth is higher. The crack extension has been observed to be predominantly transgranular by dimple formation in this alloy. A relationship between the dimple size measured on the fracture surfaces and the toughness has also been established. It is argued that the fracture toughness at the onset of fracture can be readily measured by using circumferentially notched bar tensile specimens.