Monroe is a town located in eastern Fairfield County, Connecticut, United States. The population was 19,479 at the 2010 census.
Monroe is largely considered a bedroom community of New York City, New Haven, and Bridgeport.
On May 15, 1656, the Court of the Colony of Connecticut in Hartford affirmed that the town of Stratford included all of the territory 12 miles (19 km) inland from Long Island Sound, between the Housatonic River and the Fairfield town line, to include the southern portion of present-day Monroe. In 1662, Stratford selectmen Lt. Joseph Judson, Captain Joseph Hawley and John Minor secured all the written deeds of transfer from the Golden Hill Paugussett Indian Nation for this vast territory that comprises the present-day towns of Trumbull, Shelton and Monroe. In 1671, Stratford purchased from the Paugusset Indians the territory which included the remainder of the northern portions of Monroe, Trumbull and Shelton, in what is known as "The White Hills Purchase", and officially annexed it to the Township of Stratford.
Monroe incorporated as a town in 1823. The community is named after James Monroe, fifth President of the United States.
According to the United States Census Bureau, the town has a total area of 26.3 square miles (68 km2), of which 26.1 square miles (68 km2) is land and 0.2 square miles (0.52 km2), or 0.76%, is water. The Pequonnock River begins in Monroe in Wolfe Park. Monroe borders Lake Zoar, a reservoir on the Housatonic River formed by Stevenson Dam.