Government authorities use resources on information campaigns in order to inform citizens about relevant policy changes. The motivation is usually that individuals sometimes are ill-informed about the public policies relevant for their choices. In a survey experiment where the treatment group was provided with public information material on the social security system, we assess the short- and medium-term knowledge effects. We show that the short run effects of the information on knowledge disappear completely within 4 months. The findings illustrate the limits of public information campaigns to improve knowledge about relevant policy reforms.