Learners may be uncertain about whether encountered information is true. Uncertainty may encourage people to critically assess information's accuracy, serving as a kind of desirable difficulty that benefits learning. Uncertainty may also have negative effects, however, leading people to mistrust true information or to later misremember false information as true. In three experiments, participants read history statements. In one condition, all statements were true, and the participants knew it. In the other two conditions, some statements were true, and others were false. Participants were either told the statements' accuracy or they guessed the statements' accuracy prior to feedback, a manipulation we refer to as truth-checking. All participants were then tested on recalling the true information and on recognising true versus false statements. We observed a significant benefit of truth-checking in one of the three experiments, suggesting that truth-checking may have some potential to enhance learning, perhaps by inducing people to encode to-be-learned information more deeply than they would otherwise. Even so, the benefit may come at a cost-truth-checking took significantly longer than study alone, and it led to a greater likelihood of thinking false information was true, suggesting costs of truth-checking may tend to outweigh benefits.