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 2010 census, the township's population was 14,432, reflecting an increase of 3,577 from the 10,855 counted in the 2000 Census, which had in turn declined by 439 from the 11,294 counted in the 1990 Census.