South Fallsburg is a hamlet in Sullivan County, New York, United States. The population was 2,870 at the 2010 census.South Fallsburg is located within the town of Fallsburg on Route 42.The town is home to singers Gavin & Joey DeGraw, Yeshiva Gedolah Zichron Moshe and for many years, author Andrew Neiderman, who taught high school English.