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.
Ellwood City is located at 40°51′40″N 80°17′05″W (40.860983, -80.284849).
According to the United States Census Bureau, the borough has a total area of 2.4 square miles (6.2 km2), of which 2.3 square miles (6.0 km2) is land and 0.1 square miles (0.26 km2), or 2.09%, is water.
As of the census of 2000, there were 8,688 people, 3,716 households, and 2,393 families residing in the borough. The population density was 3,716.6 people per square mile (1,433.5/km2). There were 4,006 housing units at an average density of 1,713.7 per square mile (661.0/km2). The racial makeup of the borough was 98.22% White, 0.81% African American, 0.09% Native American, 0.23% Asian, 0.18% from other races, and 0.47% from two or more races.