The first to settle in Tenafly were the Dutch in the late 1600s. The name "Tenafly" is derived from the Dutch words "Tiene Vly" or "Ten Swamps" which was given by Dutch settlers in 1688.
Tenafly was incorporated as a borough on January 24, 1894, under an Act of the New Jersey Legislature from portions of the now-defunct Palisades Township, based on the results of a referendum held the previous day, at the height of the Boroughitis phenomenon sweeping through Bergen County at the time.
New Jersey Monthly magazine ranked Tenafly as the 65th best place to live in New Jersey in its 2008 rankings of the "Best Places To Live" in New Jersey.
As of the census of 2000, there were 13,806 people, 4,774 households, and 3,866 families residing in the borough. The population density was 2,993.4 people per square mile (1,156.3/km). There were 4,897 housing units at an average density of 1,061.8/sq mi (410.1/km). The racial makeup of the borough was 76.79% White, 0.96% African American, 0.09% Native American, 19.08% Asian, 0.02% Pacific Islander, 1.40% from other races, and 1.67% from two or more races. Hispanic or Latino of any race were 4.65% of the population. 9.0% were of Irish, 8.8% American, 8.5% Italian, 8.2% Russian and 5.0% Polish ancestry according to Census 2000. 67.1% spoke English, 9.1% Korean, 5.1% Spanish, 3.7% Chinese or Mandarin, 3.1% Hebrew, 1.9% Japanese, 1.5% German, 1.3% Russian, 1.3% Greek, 1.2% Italian, 1.1% Tagalog, 1.0% Armenian and 1.0% French as their first language.
There were 4,774 households out of which 43.9% had children under the age of 18 living with them, 70.6% were married couples living together, 8.1% had a female householder with no husband present, and 19.0% were non-families. 16.8% of all households were made up of individuals and 9.3% had someone living alone who was 65 years of age or older. The average household size was 2.86 and the average family size was 3.21.
In the borough the population was spread out with 28.3% under the age of 18, 4.7% from 18 to 24, 25.4% from 25 to 44, 26.4% from 45 to 64, and 15.2% who were 65 years of age or older. The median age was 41 years. For every 100 females there were 92.9 males. For every 100 females age 18 and over, there were 87.5 males.
2007 estimates state that the median income for a household in the borough was $109,887, and the median income for a family was $124,656. Males had a median income of $92,678 versus $61,990 for females. The per capita income for the borough was $62,230. About 2.3% of families and 3.1% of the population were below the poverty line, including 4.7% of those under age 18 and 3.3% of those age 65 or over.
Bus service to and from New York City is available via New Jersey Transit bus routes 166, and Coach USA (Red and Tan) routes 9, 14, 20, and 84.
County Route 501, U.S. Route 9W, and the Palisades Interstate Parkway all pass through Tenafly. There are no exits on the Palisades Interstate Parkway in Tenafly; nearest interchanges are in Englewood Cliffs to the south, and Closter in the north.