We designed a retrospective cohort study for exploring the impact of municipality-level income inequality, based on the Gini 1986, 2004 indices, on all-cause old-age mortality among the older Swedish population during 2005-2009. We controlled for the confounding effects of individual and regional correlates and the lag effects of inequality by using multilevel logistic regression. The effects of income inequality were not consistent across age cohorts and, among the youngest cohorts, were negligible. This study reiterates that individual-level economics rather than the immediate or lagged effects of income inequality matter more for old-age mortality, even after controlling for individual and regional factors.