Background: The stigma associated with HIV/AIDS represents a significant issue. It can hinder help-seeking behaviours, fracture relationships, conceal prevalence rates and curtail public health initiatives to reduce HIV/AIDS. Culture is known to shape this stigma – it influences how individuals and the communities they represent understand the causes of HIV/AIDS, how it can and should be treated, and how people living with HIV/AIDS (PLWHA) should be regarded. Following recent increases in both HIV/AIDS and cross-cultural migration, this study determines the effect of cross-cultural integration on the tendency to stigmatise PLWHA. Methods: This was achieved by surveying adults who are at the nexus of two dissimilar cultures – adults from the Australian–Iranian community (n = 236). While the Iranian culture is largely collectivistic, the Australian culture is largely individualistic. Results: Survey results indicated the respondents represented a collectivistic (44.1%), transitional (33.5%) or an individualistic (22.4%) culture. Those within the collectivistic culture held the most stigmatising views about PLWHA, supporting coercive policies and reporting they would avoid PLWHA. Those within the individualistic culture held the most positive attitudes. Furthermore, regression analysis indicated that movement from a collectivistic to an individualistic culture significantly reduced stigmatising attitudes towards PLWHA. Conclusions: This study is the first to demonstrate the benefits afforded by an individualist culture, particularly for PLWHA. The article concludes with a discussion on the implications associated with these findings, particularly for researchers and practitioners within the health promotion field.