Huntsville is the most populous city in the U.S. state of Alabama. It serves as the county seat of Madison County, though its boundaries extend into Limestone, Marshall, and Morgan counties. The city's population was recorded at 215,006 during the 2020 census, ranking it as the 100th-most populous city in the United States.
The Huntsville metropolitan area has an estimated 542,000 residents, making it the second-most populous metropolitan area in Alabama. As of July 1, 2025, the city's population was estimated to be 249,102, representing a 15.9% increase since 2020 and placing it among the top 20 fastest-growing cities in the United States.