The Western population is growing older. Nevertheless, few studies examine the manner in which seniors are gradually demobilized from voting, partly because they are difficult to reach with surveys. Using a unique government records dataset of the actual turnout from the 2009 Danish municipal elections, we show how turnout for seniors falls more than 30 percentage points between ages 60 and 90. Though declining health matters, it is far from the entire story. Much of the turnout decline can be explained by the disruption of social ties. Withdrawing from the labour market demobilizes people. Seniors also tend to live alone more often than the general population, meaning that they receive less social encouragement to vote. We also look into why turnout drops faster for women than for men. Women lose their social network earlier than men. They are on average widowed and live alone at an earlier age than men, since women live longer and are typically younger than their husbands. Older generations of women are also less educated and have lower job market affiliation than men.