3 Reasons Not to Buy Your Groceries at Costco

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One of the primary benefits of getting a Costco membership is to save money on grocery purchases. Costco can offer lower prices than many of its competitors because it sells these items in bulk. You'll generally spend less on a per-ounce or per-unit basis than you would at a traditional supermarket.

You can save even more money on groceries at Costco by purchasing the Kirkland version of whatever it is you're looking for. Costco specifically aims to sell its signature Kirkland products for at least 20% less than what it sells national brands for. So a $10 bulk box of cereal from a brand you know might only cost you $8 (or less) if you buy the Kirkland version.

But while you can potentially save a lot of money by buying groceries at Costco, that's not necessarily a smart move. Here are a few good reasons not to buy groceries at Costco.

1. You don't do a lot of cooking

Costco can be a lifeline for people who do a fair amount of cooking at home. You can buy everything from grains to oil to spices in bulk, thereby lowering your costs.

But if you don't tend to cook very often, then buying these items at Costco doesn't make a lot of sense. Believe it or not, oils and spices don't have an unlimited shelf life, and their quality can degrade over time. If you only cook once a week, then you're probably better off buying these items in smaller quantities.

2. You don't have a large household

If you have a larger household, then loading up on perishable items at Costco could be a nice source of savings. But if your household is just you, or you and a partner, you may not be able to use up your perishables before they start to go bad.

Say you cook pretty often, so you decide to buy ground beef from Costco in bulk. If it's just you, there may only be so many meatballs you can eat in a single week.

Granted, some items do freeze well. But you'll need to be careful with bulk grocery purchases when you're talking about perishables specifically.

3. You don't have a lot of room to store food

Regardless of your cooking habits and household size, you need to be realistic about the amount of storage space you have at home. And if you're limited to a tiny freezer and smaller-sized fridge, then it may not make sense to buy your groceries at Costco.

Cramming too many items into a fridge isn't a good idea. You risk having your fridge work overtime to maintain its temperature, and things might get cooled unevenly so that the items in the back wind up frozen. That's not what you want in the context of products like butter and milk.

A Costco membership could still make sense even if you never buy groceries there

Buying bulk groceries at Costco isn't always a good idea, so it's important to think carefully before spending the money on them. That said, even if you never buy groceries at Costco, a membership could still pay off.

You might save a lot of money on household essentials at Costco, from tissues to paper towels to laundry detergent. And you might benefit from buying items like electronics from Costco due to the competitive prices and extended warranty you get. So don't assume you shouldn't get a Costco membership, even if buying groceries in bulk isn't the right thing for you.

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