Although the greater longevity of married people as compared with unmarried persons has been demonstrated repeatedly, there have been very few studies of a comparative nature. We use log-linear rate models to analyze marital-status-specific death rates for a large number of developed countries. The results indicate that divorced persons, especially divorced men, have the highest death rates among the unmarried groups of the respective genders; the excess mortality of unmarried persons relative to the married has been generally increasing over the past two to three decades; and divorced and widowed persons in their twenties and thirties have particularly high risks of dying, relative to married persons of the same age. In addition, the analysis suggests that a selection process is operating with regard to single and divorced persons: the smaller the proportion of persons who never marry or who are divorced, the higher the resulting death rates.