Centreville is an incorporated town in Queen Anne's County, Maryland, United States on the Delmarva Peninsula. Incorporated in 1794, it is the county seat of Queen Anne's County. The population was 4,285 at the 2010 census. The ZIP code is 21617 and the area codes are 410 and 443. The primary local telephone exchange is 758. It hosts the Queen Anne's County Fair each summer and was home to three franchises during the existence of the Eastern Shore Baseball League—the Colts, Red Sox, and Orioles.