Benthic foraminifera are common and distinct elements of Late Triassic reefs. It has been observed that different subenvironments of carbonate platforms contain different associations. These, however, have never been a focus of a taphonomic study. The assessment of taphonomic processes affecting benthic foraminifera along a transect of the Rhaetian reef-rimmed platform on Mount Begunjščica in Slovenia is based on thin-section analyses. The foraminiferal assemblage of the open lagoon consists primarily of autochthonous and parautochthonous specimens. Boring into the tests' interior and cyanobacterial encrustation are characteristic of areas with low sedimentation rates. Foraminifera found in tidal-inlet channels transecting the lagoon were accumulated from adjacent subenvironments and are characterized by abrasion. Back-reef sand and interstices of the lithoclastic rudstone of the central-reef area contain the most diverse foraminiferal assemblages, consisting of mixed parautochthonous and allochthonous specimens. Whereas back-reef sandstone beds contain species typical for the back-reef and the central-reef areas, the central-reef breccia contains a distinctively high proportion of Galeanella, Decapoalina (former “Sigmoilina”), and Alpinophragmium. Understanding the post-mortem processes that modified foraminiferal taphocoenoses allows us to consider these factors in future paleoecological studies of Late Triassic foraminifera.