Entrín Bajo is a municipality in the province of Badajoz, in the Extremadura region of southwestern Spain. It lies within the comarca of Tierra de Badajoz, in the lowlands near the Guadiana river basin, close to the Portuguese border that runs through this part of Extremadura.
The municipality is small and rural, with a population recorded as 605 inhabitants in the 2005 census (INE). Like many settlements in the province of Badajoz, it is a compact village surrounded by open countryside, with an economy historically tied to agriculture.
Entrín Bajo should not be confused with other places bearing similar names in Spain; it is a distinct municipality within Badajoz, and its administrative identity is defined by that province and by the autonomous community of Extremadura.