[11] The community was formerly known as East Keansburg and was renamed North Middletown by municipal ordinance around 1988.

It is bordered to the east by Port Monmouth and to the west by the borough of Keansburg.

New Jersey Route 36 runs along the southern border of the community, leading east 5 miles (8 km) to Atlantic Highlands and west the same distance to Keyport.

According to the U.S. Census Bureau, North Middletown has a total area of 0.434 square miles (1.124 km2), all land.

[1] The 2010 United States census counted 3,295 people, 1,142 households, and 859 families in the CDP.

[11] At the 2000 United States Census[6] there were 3,165 people, 1,026 households and 819 families living in the CDP.

16.3% of all households were made up of individuals, and 6.9% had someone living alone who was 65 years of age or older.