San Antonio is a city in the U.S. state of Texas. It is the seventh-most populous city in the United States, second-most populous city in Texas and second-most populous city in the Southern U.S., with a population of 1.43 million at the 2020 census. The San Antonio metropolitan area, with an estimated 2.76 million residents, ranks as the third-largest metropolitan area in Texas and the 24th-largest in the nation. It is the county seat of Bexar County.