The integration of planktonic foraminiferal assemblage, oxygen stable isotope values, and AMS 14C dating allows a more precise chronology of biostratigraphic events recorded in cores GL-74 and GL-75 collected from Campos Basin (southeastern Brazil). This study documents that the third event of disappearance of Pulleniatina plexus (Pulleniatina obliquiloculata biohorizon 3 = YP.3) occurred simultaneously in Campos and Santos Basins around 43 ka. The results also show that the event of higher abundance of Globorotalia crassaformis, the so-called Globorotalia crassaformis Optimum Event (GcOE), occurred between ca. 84 and ca. 71 ka (ca. 13 ka duration), and was also simultaneous in both basins. This study supports the GcOE as an important biostratigraphic marker event in the southeastern Brazilian margin. We propose a revised subdivision of the last glacial Zone Y into subzones Y1, Y2, and Y3. Nevertheless, it is fundamental to establish the true geographic range, as well as building a more robust chronology for the GcOE, using other cores from other South Atlantic basins.