This study investigates single pass and multipass (three-pass) welding effects on 304 austenitic stainless steel (ASS) corrosion in acidic/saline environments, to enable a better understanding of the influence of heat affected zone (HAZ) on ASS corrosion susceptibility in the selected commonly used aggressive environments. Tungsten Inert Gas (TIG) welding process was used to weld the samples using 308 stainless steel filler. The corrosion behaviour of the welded samples was evaluated using immersion and potentiodynamic polarization tests. Immersion test evaluation and the analysed results showed that the single pass welds exhibited lower corrosion susceptibility in the acidic environments (H2SO4, HNO3) than in the multipass welded ASS. In contrast, using potentiodynamic polarization evaluation, the multipass welded sample, exhibited lower corrosion susceptibility than the single pass welded ASS in HNO3 environment. Essentially, the same trend of corrosion susceptibility was recorded in NaCl environments irrespective of the evaluation method.