Dallas is a city in the U.S. state of Texas and the most populous city in the Dallas–Fort Worth metroplex, the most populous metropolitan area in Texas and the fourth-most populous metropolitan area in the United States at 7.5 million people. It is the most populous city in and seat of Dallas County with portions extending into Collin, Denton, Kaufman, and Rockwall counties. With a 2020 census population of 1,304,379, it is the ninth-most populous city in the U.S. and the third-most populous city in Texas after Houston and San Antonio. Located in the North Texas region, the city of Dallas is the main core of the largest metropolitan area in the Southern United States and the largest inland metropolitan area in the U.S. that lacks any navigable link to the sea.

The Dallas–Fort Worth metroplex, officially designated Dallas–Fort Worth–Arlington by the U.S. Office of Management and Budget, is the most populous metropolitan statistical area in the U.S. state of Texas and the Southern United States, encompassing 11 counties. Its historically dominant core cities are Dallas and Fort Worth. It is the economic and cultural hub of North Texas. Residents of the area also refer to it as DFW, or the Metroplex. The Dallas–Fort Worth–Arlington metropolitan statistical area's population was 7,637,387 according to the U.S. Census Bureau's 2020 census, making it the fourth-largest metropolitan area in the U.S. and the fifteenth-largest in the Americas. In 2016, the Dallas–Fort Worth metroplex had the highest annual population growth in the United States. By 2023, the U.S. Census Bureau estimated that the Dallas-Fort Worth metropolitan area's population had increased to 8,100,037, with the highest numerical growth of any metropolitan area in the United States.