North Merrick is located on the south shore of Long Island. It is known for being a middle class neighborhhod and having a large Italian and Irish population.
There were 3,963 households out of which 38.3% had children under the age of 18 living with them, 69.6% were married couples living together, 9.7% had a female householder with no husband present, and 17.1% were non-families. 14.1% of all households were made up of individuals and 8.4% had someone living alone who was 65 years of age or older. The average household size was 2.99 and the average family size was 3.30.
In the CDP the population was spread out with 25.2% under the age of 18, 6.0% from 18 to 24, 29.9% from 25 to 44, 23.5% from 45 to 64, and 15.4% who were 65 years of age or older. The median age was 39 years. For every 100 females there were 94.9 males. For every 100 females age 18 and over, there were 89.5 males.
The median income for a household in the CDP was $80,786, and the median income for a family was $105,190. Males had a median income of $80,054 versus $48,459 for females. The per capita income for the CDP was $30,791. About 1.7% of families and 3.5% of the population were below the poverty line, including 4.7% of those under age 18 and 4.2% of those age 65 or over.
North Merrick is protected by a volunteer fire department that is responsible for one of the smallest fire districts in Nassau County covering 2.1 square miles. The North Merrick Fire Department has approximately 85 members using 16 pieces of apparatus located at one station.