Avondale is a borough in Chester County, Pennsylvania, United States. The population was 1,265 at the 2010 census. Avondale is located at 39°49′32″N 75°46′58″W / 39.82556°N 75.78278°W / 39.82556; -75.78278 (39.825609, -75.782763). According to the United States Census Bureau, the borough has a total area of 0.5 square miles (1.3 km²), all land.