According to the United States Census Bureau, the town has a total area of 13.9 square miles (36.0 km²), of which, 5.4 square miles (14.0 km²) of it is land and 8.5 square miles (22.0 km²) of it (61.22%) is water. Southport is on Southport Island in the mouth of the Sheepscot River. The Town of Southport constitutes the whole of Southport Island.

Southport Area Code is 207

• Town of Southport, ME - P.O. Box 149, Southport, Maine 04576
  Telephone: 207-633-3328
• Hendricks Hill Museum - 419 Hendricks Hill Road, Southport, Maine 04576
  Telephone: 207-633-1102