Research on social stratification has mostly focused on working-age populations. With rapidly aging populations increasing across the rich world, inequalities at older ages are an increasingly relevant part of how contemporary societies are stratified. In this talk, I highlight an aspect of inequality that has been largely unexamined—the inequality of lifetime accumulated pensions, and present novel findings from Sweden. Using Swedish register data covering the retired population born from 1918–1939, we found that lifetime pensions are much more unequal than pre-retirement earnings and yearly pensions. Our findings show that the demographic driver—mortality—is the most important factor explaining both the inequality of lifetime pensions within cohorts and changes across cohorts. Pension policies can affect lifetime pension inequality, but such effects are limited in magnitude unless they directly affect the number of years of receiving pensions.