In two studies we investigate whether social exclusion a well studied, common and quite painful socialexperience-influences people’s perceptions of novel social networks. In a first study, exclusion experi-ences led people to report that novel networks were more dense relative to those who had not beenexcluded. As predicted, this was true only for social networks; exclusion had no impact on percep-tions when networks were described as geographical. In a follow-up experiment, participants watcheda custom-created video, depicting avatars interacting in social scenes and they were asked to report theties among the avatars in the video. Exclusion experiences led people to see network ties where noneexist (i.e., false positives), though there was no effect for exclusion (versus inclusion) on reports of falsenegatives. Results indicate that common social experiences systematically shape network perceptions,leading people to seeing novel social networks as more densely connected than they are.