There are 104 Post Offices in Riverside County, California, serving a population of 2,355,002 people in an area of 7,205 square miles. There is 1 Post Office per 22,644 people, and 1 Post Office per 69 square miles.
In California, Riverside County is ranked 54th of 58 counties in Post Offices per capita, and 24th of 58 counties in Post Offices per square mile.