Bayou Vista is a census-designated place in St. Mary Parish located in the U.S. state of Louisiana. It is included in the Morgan City Micropolitan Statistical Area. It has a total area of 1.9 square miles at 29°41′26″N 91°16′09″W. The elevation is 7 feet above sea level. As of the 2010 census data, it had a total population of 4,652. The population density was 997.0/sq mi. Estimated per capita income in 2016 was $21,656. It has Zip code 70380.