Wildfire presents a growing threat across the American West. We conducted an online choice experiment in Western Colorado to assess how social interactions affect wildfire mitigation decisions through two distinct pathways: risk interdependency (neighbors’ conditions affect perceived wildfire risk) and social norms (neighbors’ actions affect perceptions of appropriate mitigation choices). In contrast to key observational studies, we find that participants are less likely to choose to mitigate when they have more neighbors with sparse vegetation. This effect operates through the risk interdependency pathway: sparse vegetation on neighboring properties lowers participants’ wildfire risk perceptions and appears to be viewed as a substitute for one’s own mitigation actions. In this context, where neighbors are nameless and faceless, social norms do not counteract this negative effect. To reconcile this experimental result with observational studies, we discuss how both risk interdependency and social norms are influenced by geographical and social contexts and highlight how these insights can inform future research and policy action.