Riverdale (formerly, Liberty Settlement) is a census-designated place (CDP) in Fresno County, California, United States. The population was 3,153 at the 2010 census, up from 2,416 at the 2000 census. Riverdale is located 23 miles (37 km) south of Fresno, at an elevation of 223 feet (68 m).
According to the United States Census Bureau, the CDP has a total area of 3.9 square miles (10.2 km²), all of it land.
The first post office at Riverdale opened in 1875. The place was originally called Liberty Settlement, but was renamed due to its proximity to the Kings River.