Heat impacts are disproportionately higher in urban areas since cities experience localized warming (also called urban heat islands) on top of background global warming and now house most of the human population. Due to the heterogeneity of cities, there is also a large difference in outdoor heat hazard between neighborhoods. Recent policy and scientific discourse around heat has often focused on environmental disparities within cities, since there is strong evidence that heat hazard is higher in poorer urban neighborhoods. However, almost all the evidence on income-based disparities in heat hazard come from multi-city assessments for the U.S. These disparities are functions of population distributions within cities, with the present urban population distribution in the U.S. being the result of a history of discriminatory practices and nation-specific cultural norms and preferences. It is unknown whether the patterns for disparities in heat hazard seen in the U.S. would translate to cities in the Global South, which have different historical and present cultural norms, because of the lack of fine-grained income/wealth estimates that can resolve intra-urban variability. Here, we use various gridded datasets, including satellite-derived estimates, to demonstrate that wealthier urban neighborhoods generally have higher heat hazard in the Global South, the opposite of the results seen for U.S. cities. This is because income/wealth distributions within these cities result from their unique cultural history and population-level living preferences, and do not follow typical U.S. patterns. Parallel analyses of intra-urban vegetation distributions, which modulate heat hazard, show more nuanced relationships with income, though the general results still differ from the those for the U.S. We recommend being cautious about treating scientific evidence from U.S. cities as the universal norm for understanding intra-urban heat risk and encourage more comprehensive urban heat vulnerability studies for the Global South.