Green Island is a coterminous town-village in Albany County, New York, United States some 8 miles (13 km.) north of Albany, New York. Green Island is one of only five such town-village amalgams in New York. The population was 2,620 at the 2010 census, and the postal code is 12183. While the town of Green Island was once an island, it was connected to the mainland on the west side of the Hudson River in the 1960s.