The Mačva District is one of eight administrative districts of Šumadija and Western Serbia. It expands in the western parts of Serbia, in the geographical regions of Mačva, Podrinje, Posavina, and Pocerina. According to the 2011 census results, it has a population of 298,931 inhabitants. The administrative center of the Mačva district is the city of Šabac.