Most people in the United States recognize the reality of climate change and are concerned about its consequences, yet climate change is a low priority relative to other policy issues. Recognizing that belief in climate change does not necessarily translate to prioritizing climate policy, we examine psychological factors that may boost or inhibit prioritization. We hypothesized that perceived social norms from people’s own political party influence their climate policy prioritization beyond their personal belief in climate change. In Study 1, a large, diverse sample of Democratic and Republican participants (
N= 887) reported their prioritization of climate policy relative to other issues. Participants’ perceptions of their political ingroup’s social norms about climate policy prioritization were the strongest predictor of personal climate policy prioritization—stronger even than participants’ belief in climate change, political orientation, environmental identity, and environmental values. Perceptions of political outgroup norms did not predict prioritization. In Study 2 ( N= 217), we experimentally manipulated Democratic and Republican descriptive norms of climate policy prioritization. Participants’ prioritization of climate policy was highest when both the political ingroup and the outgroup prioritized climate policy. Ingroup norms had a strong influence on personal policy prioritization whereas outgroup norms did not. These findings demonstrate that, beyond personal beliefs and other individual differences, ingroup social norms shape the public’s prioritization of climate change as a policy issue.