Administrative Assistant salary at Ontario

The average administrative assistant salary at Ontario was $87,805 , which is 7 percent lower than the average salary for this job in California, but 17 percent higher than the national average for this job . Administrative Assistant salaries at Ontario typically range from $87,447 to $99,856 (25th to 75th percentile). The highest reported administrative assistant salary was $109,931. There are 20 employees at Ontario with the job title administrative assistant.