Prepaid postage using pre-stamped envelopes to affect turnout costs

Voter participation in elections is important for representational reasons but also because it helps to support the legitimacy of the election outcome. In a recent paper, Schelker and Schneiter (2017) show with data from only one Swiss canton that a small policy intervention (return envelopes with prepaid postage) can lead to substantially increased voter turnout rates. We revisit this finding and extend the analysis to all cantons that allow municipalities to offer free return postage. We find that a credible estimate of the effect is somewhat smaller but still positive and significant. We also document that this effect is not constant but stronger for larger municipalities than for smaller municipalities. Our interviews point to a likely mechanism. These results show that return envelopes with prepaid postage are an effective policy to increase participation, but mostly for large municipalities.