Missouri's third congressional district is in the eastern and central portion of the state. It stretches from the southern part of Columbia (including the University of Missouri) and the state capital of Jefferson City in the west to St. Charles County (including the large suburbs of St. Charles, St. Peters and Wentzville) and western Jefferson County in the east. The district took its current form in 2023, when Cooper and parts of Boone counties were added to the district, while Franklin and most of Warren counties were instead drawn into the 2nd district, and much of Lincoln County moved to the 6th district. Its current representative is Republican Bob Onder.