Portales is a city in and the county seat of Roosevelt County, New Mexico, United States. Its population was 12,280 at the 2010 census. Portales is located near the larger city of Clovis, and Cannon Air Force Base, a major contributor to the economy of the region. Eastern New Mexico University opened in Portales in 1934 as Eastern New Mexico Junior College, and has since grown to become the third-largest university in the state.