Sioux Falls is the most populous city in the U.S. state of South Dakota and the 131st-most populous city in the United States. It is the county seat of Minnehaha County and also extends into Lincoln County to the south, proximate with the Iowa state line. As of 2020, Sioux Falls had a population of 192,517. The Sioux Falls metro area accounts for more than 30% of the state's entire population.