Pennsylvania's twentieth congressional district was a congressional district in southwestern Pennsylvania. It was created following the 1830 Census and was disbanded after the 2000 Census removed two representatives from Pennsylvania. The 18th district is generally considered to be its successor, although the 12th district contains some of its territory. Pennsylvania's 18th congressional district includes parts of Washington County, Allegheny and Westmoreland Counties. Republican Tim Murphy has represented the district since 2003. The district is concentrated in the southern suburbs of Pittsburgh.