The Subtropical Doradito (Pseudocolopteryx acutipennis) is a small tyrannid that breeds in shrubby marshlands of South America. Post-breeding migration occurs in both mountain and lowland populations, but little is known of the destination(s) of these birds. Subtropical Doraditos have recently been found during the southern winter, or non-breeding season, in several localities in southern Amazonian Brazil and the Pantanal, with four reports from coastal Brazil. Our observations and censuses in coastal marshes of southeast and southern Brazil have produced eight records of Subtropical Doradito in the states of Paraná and São Paulo. In light of comparison with other Brazilian records compiled for this study, we suggest that coastal winterers are likely latitudinal migrants from geographically restricted breeding grounds in the Pampas of Argentina. In addition, we discuss conservation problems for the Subtropical Doradito in coastal wintering areas.