6. Join a warehouse club. Bulk retailers such as BJ’s Wholesale Club and Costco can be 20 to 50 percent cheaper than regular grocery stores when it comes to products like condiments, coffee, bottled water, and canned beans and vegetables. (The supermarket has better deals on items like produce, chips, and cookies.) Visit the websites of clubs like BJ’s (bjs.com; $45 annual fee), Costco (costco.com; $50), and Sam’s Club (samsclub.com; $40) to determine which has the best location and product mix for you, then join online.