This State Is Home To The World's Largest Costco

If you decide to finally buy a Costco membership, and you're also up for a road trip, make a pit stop in Salt Lake City, Utah, to experience the chain's largest store. With 235,000 square feet of space (which is about 5.4 acres), customers need a map to walk around the aisles without getting lost. 

The store first opened in 1994 as a 165,000-square-foot consumer warehouse filled with scratch-made Costco bakery items, aisles upon aisles of household products, and, of course, the famous Costco food court with its hot dogs and smoothies. Then, 70,000 square feet were added to make room for a business center. At the time, there was no guarantee that a standalone Costco business center would appeal to educational organizations, restaurants, and commercial businesses, so the company added it to the existing warehouse to test the market. Met with overwhelmingly positive response, the business center also makes the Salt Lake City location the first-ever hybrid Costco model in America. But, recently, another state has been vying for the title of World's Largest Costco.

In 2023, Costco submitted a proposal to build a 241,000-square-foot warehouse in Fresno, California, to replace an existing store in the area. The new warehouse would be as large as four football fields, complete with plenty of Costco perks to take advantage of, like a car wash and 32 gas station pumps. With 6,000 additional square feet of real estate, the proposed store would be bigger than the Salt Lake City location. 

Although Costco fans were excited about the proposal, other locals and environmental groups had concerns about traffic. In April 2024, Fresno's City Council approved the proposal following updates to reduce noise and streamline traffic. A month later, the city was sued by residents from the Herndon-Riverside Coalition for Responsible Planning and Development. The group requested the approval be denied, arguing that an environmental impact study showed evidence that Costco's plans didn't consider alternative building sites, or the increased greenhouse gas emissions caused by transportation in the area. 

In July 2025, a judge placed Costco's Fresno warehouse project on hold indefinitely, pending a revised environmental impact report by the City of Fresno. There is also zero mention of upcoming openings in the area, on the new location section of Costco's website.