PEOPLE tend to use mental accounting to keep track of money, inherently reserving about 25 percent of that unconscious budget for impulse buys, a portion called the “slack budget,” said Liz Crawford, author of “The Shopper Economy.” And while these unplanned purchases may not do major harm to your wallet, they do tend to damage to your waist.

It’s better if you always shop with a list. When you wrote down your must-buys at home, you included dark chocolate but not brownies, so use it as a reference for when you feel your willpower weakening around a seemingly appealing bargain.

When you’re waiting in a seemingly endless line, you become a prime target for impulse buys. Items like candy, which you can munch on then and there, and magazines, which you can read while you have nothing else to do, are intentionally positioned by the register in order to increase your total purchase. To discipline yourself, use a basket rather than a large shopping cart, or even carry everything in your arms to help guarantee that you’re only picking up what you truly need.

When a shopping cart is your only option, if you have your entire family’s weekly groceries, only get in line to pay once you have everything on your list. Consider the queue a time of shopping embargo.

We live in a self-rewarding culture, which can lead to foolish spending on food and beyond. Women are typically responsible for their families, which means that they go to the store every week and push around the cart, even if they’re not up to it. It’s a task you do for others, and after taking care of everyone else, it’s easy to think you deserve a little something for yourself. You most certainly do — but perhaps not of the hot, salty pretzel variety, which tends to be more about the thrill of buying than about actually enjoying your purchase.

If your grocery shopping routine always falls on a certain day, get in the habit of scheduling an activity that you enjoy afterward, like grabbing coffee with a girlfriend or walking your dog in the park, which can help motivate you to get the chore done as efficiently as possible.