Turnout rates are in decline in advanced democracies, but the consequences of this trend for inequalities in participation have not yet been investigated in a large, comparative study. In this article, we investigate educational inequalities in six countries. First, we examine whether Tingsten’s law of dispersion holds and whether decreasing turnout rates imply more unequal participation. Subsequently, we examine whether the more gradual over-time process of declining turnout rates leads to biased participation. We show that the participation gap between low- and high-educated citizens is growing. This pattern is strongest in countries where turnout rates have decreased most.