This article describes the long-term trends in marital status mortality differences in the Netherlands using a unique dataset relating to the period 1850–1970. Poisson regression analysis was applied to calculate relative mortality risks by marital status. For two periods, cause-of-death by marital status could be used. Clear differences in mortality by marital status were observed, with strongly increasing advantages for married men and women and a relative increase in the mortality of widowed compared with non-married people. Excess mortality among single and formerly married men and women was visible in many cause-of-death categories, and this became more widespread during the last decades of the nineteenth century. Hypotheses are formulated that might explain why married men and women underwent a stronger decrease in mortality up until the end of World War II.