Residential mobility in Prehispanic Mesoamerica is of paramount importance in bioarchaeology to determine the "how, where and why" people established biological, political and economic networks. The goal of this paper is to assess the presence of non-local people on the East Coast of the Yucatan Peninsula during the Late Postclassic (AD 1200-1540), and how they might have been perceived by the local Maya people. We analyze the presence, origin and mortuary distribution of 50 individuals based on their dental and bone 87Sr/86Sr signatures in the "urban" assemblage constituted by the archaeological sites known as El Rey and San Miguelito on Isla Cancun. Both sites present a strontium ratio "plateau" between 0.7091 and 0.7092, which is considered the local signature. Seven individuals, ranging in age from 5 years old to adulthood, were detected as potentially non-local, and originating from a wide range of regions both near and distant to Isla Cancun. Funerary patterns, burial location, and dietary data do not indicate these people were treated differently from the rest of the population, at least at the moment of death. This suggests that these non-locals might not have been perceived as "foreigners" and that they had integrated into the local community. Such mobility and cultural integration could have motivated by multiple factors, including economic and trade connections, or kinship relationships.