Speaker self-ratings are a commonly used tool for assessing speaker proficiency, despite the fact that they establish a subjective basis for comparison within the community that reflects speaker attitudes, self-esteem, and status. While analyses based on these factors provide invaluable insight for sociolinguistic research, the lack of objectivity calls into question the usefulness of this method for placing speakers on the bilingual continuum. This is especially difficult in heritage communities, where speakers have been shown to be critical of their own language ability (Davidson & Lekic 2015). To enable an objective cross-speaker and cross-community comparison, the authors present a set of post-hoc measures covering proficiency factor clusters (Petersen et al. 2018) that can be applied to any pre-existing data and evaluate how these measures correlate to speaker self-ratings for three heritage communities in North America (Plautdietsch-English bilinguals, North American Icelandic-English bilinguals, and New Ulm German-English bilinguals). The results show an overall lack of correlation between the two types of assessment and connect to previous research that calls for more varied assessment of proficiency in heritage language communities (Polinsky 2018; Thompson 2015).