Does Flour Go Bad? Chefs and Registered Dietitians Say Yes—Here’s How To Tell

There are two types of people: Those who go through a bag of flour so fast that they’ve never really stopped to think whether it can expire, and those who rarely bake and have years-old sacks of it in their pantries. Hate to break it to you, but flour does go bad.

“All foods except preservatives, for example, sugar or honey, go bad eventually,” says Ariane Resnick, CNC, a chef and certified nutritionist. According to the U.S. Department of Agriculture (USDA), because flour has low moisture content and is heat-treated, it is safe to eat for a very long time, even if the expiration date has passed. The key to keeping it good is proper storage.

“Leaving it open and exposed to air will ruin the texture,” says Resnick. “Hot homes, over 78°F, will accelerate the oils in the flour going bad.” The type will dictate how long flour lasts in your cupboard.

“White flour is best for longevity. It has the bran removed, which is where the oil is contained, so it only has one gram of fat left per cup. It can easily last several years in the cupboard without issue,” says Resnick. “Conversely, all whole food flours, including whole wheat flour, will last a maximum of a couple of years at room temperature. The more oil, the faster it will turn. That makes high-fat flours, such as coconut, which typically has 16 grams of fat per cup, the fastest to go bad.”