[7] Ontario Mills is home to many designer-label outlet stores, including Tory Burch, Ann Taylor, Ralph Lauren, Hugo Boss, DKNY, Tommy Hilfiger, Perry Ellis, Calvin Klein, Coach, Kate Spade, LACOSTE and Michael Kors.

[citation needed] On December 13, 1996, AMC Ontario Mills 30 opened, making it the largest theatre in the world at the time.

An IMAX-like UltraScreen theater and a California Welcome Center operated by the entrance near the food court until 2000, when it was replaced by the Ontario IMPROV comedy club, Market Broiler, and a Nike Factory Store.

Ontario Mills was formerly home to a Vans Skate Park, which in early 2005 was closed and converted into Steve & Barry's.

The well-known Wolfgang Puck Cafe closed in early 2005 and was replaced by the Polo Ralph Lauren Factory Store.

A Neiman Marcus Last Call opened in 2012 on the former Steve & Barry's, along with an expansion of the existing Forever 21 and Nordstrom Rack stores and a new renovated food court.

On May 13, 2018 (Mother's Day), after opening the previous year, Toys R Us Outlet closed due to Chapter 11 Bankruptcy after the company announced they would be going out of business.