The Jeed Formation (Upper Maastrichtian to Lower Danian) in the Western Desert of Iraq is a new proposed mixed lithostratigraphic succession containing various rock types, including phosphatic, siliceous, calcareous, siliciclastic, and other mineralogical contents (carbonate flouraptite, quartz, calcite, dolomite, opal-CT, smectite, palygorskite, sepiolite, kaolinite, and locally zeolite). The current study presents a review compliant with ICS standards and a revised lithostratigraphic framework for the Jeed Formation, based on a synthesis of historical usage, stratigraphic evolution, and previous miscorrelations, along with contributions from new data from integrated lithological, mineralogical, and microfacies datasets. The formation has been formally redefined and recognized as the correct stratigraphic unit, thus replacing the earlier misapplied Upper Campanian-Lower Maastrichtian Digma Formation in Western Iraq. The Jeed Formation consists of two members: the Upper Maastrichtian Safra Member and the Lower Danian Trafawi Member, each subdivided into two beds: lower and upper. The upper Maastrichtian member shares the same depositional phase as the lower Danian member, with a symmetrical lithological architecture and comparable depositional basins, indicating a series of identical lithofacies controlled by regional and continental factors rather than local ones. The Cretaceous-Paleogene (K/Pg) transition is marked by a geologically significant unconformity that extends across the entire region and serves as a marker for the Safra /Trafawi member boundary. Regional correlation between the Muwaqqar Chalk Marl Formation of Jordan, the Jalamid Formation of northern Saudi Arabia, and the Dakhla Formation of Egypt highlights the role of the Jeed Formation within a continuous Maastrichtian–Danian phosphogenic belt along the southern margin of the Tethys Ocean.