Ontario Mills is a large enclosed shopping mall, marketed as an outlet mall. It is located in Ontario, California and it is one of the primary tourist attractions in the Inland Empire. It is located across the street from the former site of the Ontario Motor Speedway. Like all other Mills properties, it was first developed and once owned by the Mills Corporation. Ontario Mills is the first Mills landmark to have the racetrack layout and having a theme in its neighborhoods.It is one of three Mills landmarks in California that are now owned by Simon Property Group since April 2007. (The Block at Orange, and Great Mall of the Bay Area are the others) One of the largest shopping malls in North America, the mall opened to the public on November 14, 1996. Ontario Mills was designed by the architectural firm, F+A Architects.

The mall is near the Ontario International Airport, as well as the interchange between the Ontario Freeway(Interstate 15) and the San Bernardino Freeway (Interstate 10).