This note discusses the lithostratigraphic nomenclature used to characterise the Permian–Triassic transition at outcrop in the Oman Mountains, with emphasis on the position of the boundary between the Saiq and Mahil formations. Two inconsistent criteria for picking the Saiq/Mahil Boundary (SMB) prevail in the literature causing confusion regarding the correct position of the Permian/Triassic Boundary (PTB). The position of the PTB plays a central role in the correlation of these two formations from outcrop to the subsurface Khuff and overlying Sudair formations.