what county is rialto ca
Sponsored Topics. Rialto is a city in San Bernardino County, California, United States. According to Census Bureau estimates, the city had a population of 99,171 in 2010. Rialto is home to four major regional distribution centers: Staples, Inc., which serves stores across the entire West Coast of the United States, Toys R Us, FedEx and Target in the northern region of the city, in the Las Colinas community.