Jasper is a city in and the county seat of Jasper County, Texas, United States. Its population was 6,884 at the 2020 U.S. Census, down from 7,590 at the 2010 U.S. Census. Jasper is situated in the Deep East Texas subregion, about 40 miles west of the Texas-Louisiana state line. Jasper holds an annual Butterfly Festival the first Saturday in October to celebrate the migration of the monarch butterflies.