International sanctions are commonly used when military intervention is particularly undesirable. The recent Russian invasion of Ukraine increased the saliency of sanctions, as well as their high domestic costs for the sender states. Democratic states require public support to sustain long and costly sanctions. Yet empirical research on public perception and support for sanctions is scarce. We conduct two experimental studies on quota-representative samples in Poland and Germany using the context of the sanctions on Russia. The first study uses a novel conjoint experiment with the goal to examine how features of a sanctioning regime shape public support for sanctions. As expected, support increases with a decrease in domestic costs and increases in costs imposed on the target state. In addition, aid programs, which can mitigate domestic costs, and beneficial policy alternatives (e.g., developing sustainable energy to replace Russian oil) can enhance support. Furthermore, public support for sanctions requires larger sanctioning countries’ coalitions. In the second—information experiment—study, we find that people overestimate the sanctions’ costs for their country and that correcting this perception through the provision of estimated costs increases reported support. Yet, contrasting sanctions costs with other costs has no additional effect.