Southport is a town and archipelago in Lincoln County, Maine, United States. The population was 622 at the 2020 census. It includes the neighborhoods of Capitol Island, Cozy Harbor, East Side, Newagen, Pine Cliff, and West Southport, and the village of Squirrel Island. The majority of the town's residents live on its main island, Southport Island.

Lincoln County is a county located in the U.S. state of Maine. As of the 2020 census, the population was 35,237. Its seat is Wiscasset. The county was founded in 1760 by the Massachusetts General Court from a portion of York County, Massachusetts and named after the English city Lincoln, the birthplace of Massachusetts Bay Provincial Governor Thomas Pownall.