Huntsville is the most populous city in the U.S. state of Alabama. The population was 215,006 at the 2020 census and was estimated to be 225,564 in 2023, making it the 100th-most populous city in the U.S. The Huntsville metropolitan area had an estimated 527,000 residents in 2023 and is the second-most populous metro area in the state, after Birmingham. Huntsville is the seat of Madison County, with portions extending into Limestone County and Morgan County.