Political communication research identifies various effects of persuasive communication. However, it is unclear how long these effects will last over time. This contribution observes how long the effects of political communication endure in a natural experiment on the impact of the Balkan route closure announcement during the 2015/16 European refugee crisis. By utilizing this case, it overcomes the limitations of more traditional survey experiments. I demonstrate how the announcement affected people’s perceptions of the refugee crisis, asylum attitudes, and policy preferences. All effects identified are largest immediately after the announcement and then rapidly decline. Therefore, political communication can have a crucial opinion-changing effect, yet only in a limited time frame. My study adds to our understanding of the longevity of communication effects and demonstrates a methodology that can easily be replicated for other cases.