Belmar is a borough in Monmouth County, New Jersey, United States. As of the United States 2000 Census, the borough population was 6,045. The Borough of Belmar is governed under the Faulkner Act (Small Municipality) system of municipal government.What is now Belmar was originally incorporated as Ocean Beach borough by an Act of the New Jersey Legislature on April 9, 1885, from portions of Wall Township, based on the results of a referendum held two days earlier. On April 16, 1889, it became the City of Elcho borough, which lasted for a few weeks until the name was changed to the City of Belmar Borough as of May 14, 1889. The city acquired its current name, Borough of Belmar, on November 20, 1890.