ObjectivesMisinformation is a crucial problem, particularly online, and the success of debunking messages has so far been limited. In this study, we experimentally test how debunking text structure (truth sandwich vs. bottom‐heavy) and headline format (statement vs. questions) affect the belief in misinformation across topics of the safety of COVID vaccines and GMO foods.DesignExperimental online study.MethodsA representative German sample of 4906 participants were randomly assigned to reading one of eight debunking messages in the experimentally varied formats and subsequently rated the acceptance of this message and the agreement to misinformation statements about the mentioned topics and an unrefuted control myth.ResultsWhile the debunking messages specifically decreased the belief in the targeted myth, these beliefs and the acceptance of the debunking message were unaffected by the text structures and headline formats. Yet, they were less successful when addressing individuals with strong pre‐existing, incongruent attitudes and distrust in science.ConclusionsThe risk of backfire effects in debunking misinformation is low. Text structure and headline format are of relatively little importance for the effectiveness of debunking messages. Instead, writers may need to pay attention to the text being comprehensive, trustworthy and persuasive to maximize effectiveness.