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The cosmetic corrosion of welded and painted automotive hot-dip galvanized (HDG) panels in the GM scab test and outdoor exposure has been studied. A comparison was made between the performance of laser butt welds, mash seam welds and resistance spot welds. Other variables were the laser speed and the power input in the laser welding process. The underfilm corrosion in welded areas was compared with that in areas with standard scribes through the paint film. The weld areas were characterized by SEM and EDX before and after phosphating and also following corrosion testing by SEM and EDX. Corrosion products were identified by X-Ray diffraction (XRD). The best overall corrosion performance was exhibited by laser-welded panels, provided the weld area is protected from oxidation. Models for the corrosion propagation mechanisms are presented.