Planktonic Foraminifera assemblages register the several climate changes that occurred during the Quaternary. These assemblage variations (frequently abundance reversals) are used to establish bioecozones. Since climate changes are neither synchronic nor spatially homogenous, the purpose is to assess the applicability of the bioecozonations proposed for the Santos and Campos basins in the northern portion of the Pelotas Basin (South Brazilian Continental Margin). The studied grain size was >0.150 mm.