Exton is a census-designated place (CDP) in West Whiteland Township, Chester County, Pennsylvania, United States. Its population was 4,842 at the 2010 census. The Exton Square Mall is located within Exton along with several other shopping centers, making Exton the major shopping district in Chester County.
Exton lies at the intersection of U.S. Route 30 (formerly the Lancaster Road, and later the Lincoln Highway) and Pennsylvania Route 100 (Pottstown Pike). Beginning in the late 18th century, the Lancaster Road became a major transportation route between Philadelphia and the west, while what is now Route 100 was a regional north-south route to Pottstown. A theory exists that Exton was named as the "X" on the map, denoting this intersection, though more likely the village was named after one of the several Extons in the United Kingdom.
In the late 1940s, Exton became home to the Newcomen Society of the United States. The campus of the learned society was built overlooking farmland on Newcomen Road, and featured offices, a printing shop, library and museum, guest houses, a chapel and a belltower with a carillon. The Newcomen Society sold the property in the late 1990s, but its campus remains an Exton landmark serving as the headquarters of another business.