According to the United States Census Bureau, the borough had a total area of 9.232 square miles (23.910 km2), including 6.411 square miles (16.604 km2) of land and 2.821 square miles (7.307 km2) of water (30.56%)
The borough borders Closter, Cresskill, Demarest, Norwood, Rockleigh and Tenafly in Bergen County.