<p>In the manufacturing of sheet metal parts involving stretch flanging, circular hole flanging and square hole flanging processes are commonly used. Therefore, stretch flangeability of Al alloys is an important aspect in the assessment of formability for lightweighting of sheet metal parts and it refers to the local edge formability to avoid cracking during the expansion of a hole in a sheet metal part to form a flange. In this study, stretch flangeability of Al alloys has been investigated in circular and square hole flanging processes by numerical simulation and experimental validation and the results of formability, strain distribution, thinning and flange height are compared with two grades of steel. Among the five aluminium alloys investigated, AA5754 and AA5083 alloys showed highest formability in circular hole flanging indicated by their lowest minimum hole flanging coefficient (HFC_min ) which is nearly equal to that of DP600 steel. These two alloys along with AA6061 showed better formability than DP600 steel in square hole flanging process. But in general, all the materials showed lower formability in square hole flanging than in circular hole flanging due to very high strain localization causing severe thinning and failure at the corners of the hole as indicated by the effective strain and thinning distributions in the simulation. It can be concluded that AA5083, AA5754 and AA6061 have high stretch flangeability in both circular hole flanging and square hole flanging processes making them potential materials to replace steel for stretch flanging applications.</p>