Climate information plays a key role in adaptation to climate change, but providing and using it in effective ways is a challenge. Climate information often remains underutilized and even when used, its influence on policy making is far from clear. In the Netherlands, climate stress tests were introduced to inform and stimulate climate adaptation policy on a municipal level. In the stress tests, risks and vulnerabilities were estimated for scenarios of extreme precipitation, heat stress, drought, and flooding. This article examines whether and how this new tool has effectuated mainstreaming of climate adaptation information into municipal policy. Based on interviews with municipal officials and document analysis we show that the stress tests did so along two general pathways. In the ‘applied’ pathway, the stress tests were used in an instrumental way to influence policy goals and measures. In the ‘configuring’ pathway, stress tests were primarily used for learning and persuasion, and mostly influenced problem perceptions and actor involvement. In the ‘applied’ pathway, the accuracy and resolution of the information were key factors; in the ‘configuring’ pathway, its influence depended on the accessibility of information and the kind of interaction during policy formulation. Which of the pathways predominated depended on how an adaptation problem fitted with existing policy arrangements. The findings show that stress tests are a promising tool for policy mainstreaming and for promoting local climate adaptation. They also highlight the importance of identifying the pathways of information use, in order to increase the impact of climate information.