Westside (formerly, O'Neill) is an unincorporated community and census designated place (CDP) in Fresno County, California. It is located northeast of Coalinga, at an elevation of 249 feet (76 m).
Westside first appeared as a census designated place in the 2020 U.S. census.
It is in the Westside Elementary School District and the Riverdale Joint Unified School District for grades 9-12.