Little Falls is a township in Passaic County, New Jersey, United States. The township was named for a waterfall on the Passaic River at a dam near Beattie Mill. As of the 2020 census, the township's population was 13,360 reflecting a decrease of 1,072 (7.4%) from the 14,432 counted in the 2010 Census, which had in turn increased by 3,577 (33.0%) from the 10,855 counted in the 2000 Census.