ABSTRACT: Long term study of larger foraminiferal biostratigraphy from the Philippine Archipelago, combined with research on supplemental spot samples, leads to a new definition of the East Indies Letter Stages for this region, ranging from a new Tertiary a0 stage to Tertiary h. The newly recognized units, in the form of local assemblage zones of larger foraminifera, are correlated to zonation in other shallow marine carbonate sequences in the eastern and central Tethys.