Corruption—and the widespread perception of it—poses significant obstacles to development by eroding institutional trust and reducing citizens’ willingness to pay taxes. Yet efforts to improve public perceptions often fall flat, or even backfire, when information on tax agency reforms confronts entrenched beliefs about government failure. We test whether providing a credible external benchmark before highlighting government action can shift perceptions and behavior. In a survey experiment in Honduras, we find that messages focusing solely on reform have limited or negative effects. By contrast, a sequential message that first corrects pessimistic beliefs by changing the reference point and then presents institutional progress reduces perceived corruption and lowers stated tax evasion intentions. A field experiment with around 45,000 taxpayers confirms that this approach increases tax compliance, particularly among high-risk individuals and firms. The results suggest that belief updating is possible—but only when messages are structured to first address skeptical priors.