Šamac, formerly Bosanski Šamac is a town and municipality in Republika Srpska, Bosnia and Herzegovina. There are also small, uninhabited, parts located in the municipalities of Odžak and Domaljevac-Šamac, Federation of Bosnia and Herzegovina. As of 2013, the town has a population of 5,390 inhabitants, while the municipality has 17,273 inhabitants. It is situated on the right bank of the Sava river. Across the river is Slavonski Šamac in Croatia.