East Northport is a hamlet and census-designated place (CDP) in the town of Huntington in Suffolk County, New York, United States. The population was 20,217 at the 2010 census.

Soon after the initiation of a village in the Huntington area, English settlers sought to further expand their territory. On July 30, 1656, land was purchased from Chief Asharoken, head of the Matinecocks Native American tribe, part of which consisted of the land that is today known as East Northport.

Two sure communities formed in the Place now known as East Northport. The more populous concurrence known as Larkfield was located on the northern side, near Vernon Valley (now portion of Northport). Larkfield originally developed close the location of Genola Cemetery, just north of the modern-day junction of Larkfield Road, Vernon Valley Road, and Laurel Road. A second community located on the southern side was known as Clay Pitts, named for its huge deposits of red clay. This clay which had been used by Native Americans to form pottery was used by the Europeans to form bricks for construction. The house between Larkfield and Clay Pitts was without difficulty suited for agriculture, and the region prospered in the late 18th century as a successful farming community by supplying produce to markets in New York City and Brooklyn.

In 1868 the Long Island Rail Road opened a station within the village of Northport. However, just a few years cutting edge the LIRR established to change the Northport station to a extra location in Larkfield to facilitate new railway enlargement to Port Jefferson. The other railway station located at Larkfield Road and Bellerose Avenue opened upon January 13, 1873. Although the station retained the say of Northport, train conductors would speak to to it as “East of Northport”, because the station was located east of the railway junction which used to dispatch trains north to the antiquated station located in the village of Northport. Despite the fact that East Northport is primarily south of Northport, the Place became known thereafter as East Northport. The Larkfield Post Office formally distorted its pronounce to East Northport in 1910. The East Northport, New York make known office building was renamed the Jerome Anthony Ambro, Jr. Post Office Building in 1998.