Wichita is the largest city in the U.S. State of Kansas. It is the county seat of Sedgwick County. It is the 50th largest city in the United States. In 2018, the estimated number of people in Wichita was 389,255. Wichita is the main city of the Wichita metropolitan area; it had an estimated 644,888 people living there in 2018. It is in Sedgwick County, which is in the south-central part of the state.