Ellwood City is a borough primarily in Lawrence County, Pennsylvania, United States, with a small portion in Beaver County. Ellwood City is 30 miles (48 km) northwest of Pittsburgh and some 8 miles (13 km) southeast of New Castle. In the past, Ellwood City sustained many heavy industries such as steel-tube mills, steel-car works, building-stone and limestone quarries, foundries and machine shops, and coal-mining. The population was 7,921 at the 2010 census. Of the population, 7,289 lived in Lawrence County, while 632 lived in Beaver County.