Grand Isle is a town in Jefferson Parish, Louisiana, United States, located on a barrier island of the same name in the Gulf of Mexico. The island is at the mouth of Barataria Bay where it meets the gulf. As of the 2010 census, the town's resident population was 1,296, down from 1,541 in 2000; during summers, the population, including tourists and seasonal residents, sometimes increases to over 20,000. Grand Isle is statistically part of the New Orleans−Metairie−Kenner Metropolitan Statistical Area, though it is not connected to New Orleans' continuous urbanized area.