Columbia is the state capital and largest city in the U.S. state of South Carolina. The population was 129,272 according to the 2010 census. The 2011 United States Census estimates put the city at 130,591. Columbia is the county seat of Richland County, but a portion of the city extends into neighboring Lexington County. The city is the center of a metropolitan statistical area of 784,745, the second-largest within the state.