We utilize nationally representative surveys from the United States and Canada to examine the partisan divide in COVID-19 attitudes and behaviours in both countries. The ﬁrst cases of COVID-19 in both the US and Canada occurred around the same time, but government responses were starkly diﬀerent. We explore politically salient assessments of governmental performance in both countries, as well as general concern regarding COVID-19 and declarations of changes to daily routines undertaken in response to the pandemic. We ﬁnd strong partisan diﬀerences in evaluations of the government’s response to COVID-19 and conﬁdence in its ability to handle the crisis. We also ﬁnd partisan diﬀerences in concern and behavioural responses to the pandemic in both countries. However, the behavioural diﬀerences are small, suggesting that while overtly political assessments are strongly partisan this polarization is dampened down when it comes to actual behavioural responses to the pandemic.