The growing popular backlash against international institutions has resulted in several national referendum votes aimed at withdrawing from or renegotiating the membership terms of international institutions. To shed light on the systemic implications of these voter-based disintegration efforts, this paper examines how such efforts reverberate abroad. Observing other countries’ disintegration experiences allows voters to better assess their own countries’ prospects outside of existing international institutions. Depending on the nature of the disintegration experience, this may both encourage or deter them to support a similar move for their own country. The paper empirically examines this argument for the case of Brexit. It leverages original survey data from 49 488 EU-27 Europeans collected in five survey waves since the start of the Brexit negotiations and from a two-wave survey of 2241 Swiss voters conducted around the first Brexit extension in spring 2019. The results document both encouragement and deterrence effects of Brexit.