Fargo is a city in and the county seat of Cass County, North Dakota, United States. According to the 2020 census, its population was 125,990, making it the most populous city in the state and the 216th most populous city in the United States. Fargo, along with its twin city of Moorhead, Minnesota, and the adjacent cities of West Fargo, North Dakota and Dilworth, Minnesota, form the core of the Fargo–Moorhead, ND-MN Metropolitan Statistical Area (MSA). The MSA had a population of 248,591 in 2020.