Westbrook is a town in Middlesex County, Connecticut, United States. The population was 6,292 at the 2000 census. The town center is also classified by the U.S. Census Bureau as a census-designated place (CDP). Westbrook lies in the shoreline area of the state. The town is bordered by the towns of Essex, Clinton, Deep River, and Old Saybrook, where the Connecticut River empties into Long Island Sound. The Salt Meadow Unit of the Stewart B. McKinney National Wildlife Refuge is located in town.