Bethpage is an unincorporated community and census-designated place (CDP) in Sumner County, Tennessee, United States. It is located along U.S. Route 31E, northeast of neighboring Gallatin. As of the 2020 census, its population was 313, up from 288 at the 2010 census. The area has its own Post Office. The United States Postal Service ZIP code for the Bethpage area is 37022.