[21] Located in the northeastern corner of New Jersey and its Gateway Region, Demarest is part of the New York City Metropolitan Area.

[27] The borough borders the Bergen County municipalities of Alpine, Closter, Cresskill, Dumont and Haworth.

[28][29][30] The 2020 United States census counted 4,919 people, 1,655 households, and 1,416 families in the borough.

[38] The 2010 United States census counted 4,881 people, 1,597 households, and 1,404 families in the borough.

[40] As of the 2000 United States census[16] there were 4,845 people, 1,601 households, and 1,386 families residing in the borough.

This was the 19th highest percentage of Armenian American people in any place in the United States with 1,000 or more residents identifying their ancestry.

[7] The borough form of government used by Demarest is a "weak mayor / strong council" government in which council members act as the legislative body with the mayor presiding at meetings and voting only in the event of a tie.

The mayor can veto ordinances subject to an override by a two-thirds majority vote of the council.

[44][45] As of 2024[update], the mayor of Demarest Borough is Democrat Brian K. Bernstein, whose term of office ends December 31, 2026.

[3][46][47][48][49][50] On the night of the November 2018 general election, Melinda Iannuzzi won the first seat with 1,099 votes and Republican Joseph Gray won the second seat with 1,094 votes with Jim Caroll in fourth place; Later that month, once all ballots were counted and the results were certified, Carroll pulled ahead and won the second council seat up for election.

[53] Gregg Paster was appointed in October 2013 to fill the vacant seat of Blake Chroman that was due to expire at the end of 2015.

[56][57][58] For the 119th United States Congress, New Jersey's 5th congressional district is represented by Josh Gottheimer (D, Wyckoff).

[61] For the 2024–2025 session, the 39th legislative district of the New Jersey Legislature is represented in the State Senate by Holly Schepisi (R, River Vale) and in the General Assembly by Robert Auth (R, Old Tappan) and John V. Azzariti (R, Saddle River).

As of 2025[update], the county executive is James J. Tedesco III (D, Paramus), whose four-year term of office ends December 31, 2026.

[63] Bergen County's Commissioners are: Thomas J. Sullivan Jr. (D, Montvale, 2025),[64] Chair Germaine M. Ortiz (D, Emerson, 2025),[65] Joan Voss (D, Fort Lee, 2026),[66] Vice Chair Mary J. Amoroso (D, Mahwah, 2025),[67] Rafael Marte (D, Bergenfield, 2026),[68] Steven A. Tanelli (D, North Arlington, 2027)[69] and Tracy Silna Zur (D, Franklin Lakes, 2027).

[70][71][72][73][74][75][76][77] Bergen County's constitutional officials are: Clerk John S. Hogan (D, Northvale, 2026),[78][79] Sheriff Anthony Cureton (D, Englewood, 2027)[80][81] and Surrogate Michael R. Dressler (D, Cresskill, 2026).

[85] Among the borough's 2010 Census population, 63.9% (vs. 57.1% in Bergen County) were registered to vote, including 88.1% of those ages 18 and over (vs. 73.7% countywide).

[114][115] The Academy of the Holy Angels is a private middle school and college preparatory high school serving students in sixth through twelfth grade that operates under the auspices of the Roman Catholic Archdiocese of Newark.

While Demarest is a small community, there are often traffic jams at around 8:00 am and 3:00 pm when all three grammar schools let out for the day.

Demarest is served by Rockland Coaches routes 20/20T, with a stop by the Duck Pond on County Route 501 which provides service to and from the Port Authority Bus Terminal in Midtown Manhattan and the Palisades Center in West Nyack, New York, a common shopping destination for many residents.

After the borough purchased the site in 1978, the station was restored and has been listed on the National Register of Historic Places since 2004.