Gramercy is a town in St. James Parish, Louisiana, United States. The population was 3,613 at the 2010 census.
Gramercy was originally an Indian and French settlement and trading post. In 1739, much of the area which is now known as Gramercy was sold to Joseph Delille Dupart, Commissioner of Indian Nations under Jean-Baptiste Le Moyne de Bienville. The town was incorporated in November 1947. A historic sugar mill was established in Gramercy in 1895, which became the Colonial Sugar Refinery in 1902. The National Park Service has designated the site as the Colonial Sugar National Historic District.
Gramercy is located at 30°3′14″N 90°41′21″W (30.053907, -90.689154). Gramercy is bordered on the west by the town of Lutcher and on the south by the Mississippi River.
According to the United States Census Bureau, the town has a total area of 2.1 square miles (5.4 km2), of which 2.1 square miles (5.4 km2) is land and 0.04 square miles (0.10 km2) (1.42%) is water.