The Worst Things You Could Buy at Costco



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Bulk Regrets

There are many reasons to love Costco, and it's difficult to leave the store without spending $100 on things you didn't have on your list. But there are some things it just doesn't make sense to buy at warehouse stores — and some things that aren't even safe to buy at such places, like the 400,000 solar-powered LED patio umbrellas that were just recalled at Costco after multiple reports of the products catching on fire, with one incident landing a man in the hospital. But what you shouldn't buy at the wholesale giant doesn't end there. Variables such as the size of your household, how quickly you go through things, and what's important to you should all dictate whether you buy something from Costco, or whether it makes more sense financially to buy it in smaller quantities. 

Not a Costco member? Apply here.

Related: I Shopped at Costco for the First Time and This Is What I Learned

Costco Spices
Costco Spices by Lisa Pinehill (CC BY-NC-ND)
Fresh Produce Costco

Fresh Produce

Will you really go through 10 pounds of potatoes before they start sprouting? How about 17 bananas? If you have to throw out some of every large bag of produce you buy, you're not really saving money. Especially stay away from lettuce, spinach, and other delicate leafy greens unless you have specific plans for it immediately. Large fruits you have to buy whole, such as pineapples and watermelons, are also often more expensive at Costco than at your local grocery store.

Related: Which Fruits and Veggies Go Bad the Quickest and Which Last the Longest?

Costco books
Costco books by Terry Madeley (CC BY)
Smartphone's on the counter of a electronics store


If you are looking for the absolute lowest price on that exact big-screen TV model or laptop you want, Costco might not be the best place to get it. With online retailer competition so tight, they sometimes don't have the lowest price on any given model. And many of the TV and laptop models are made specifically for Costco and may cut back on features to cost less. Make sure to check out the technical specs to be sure there isn't a missing feature you want.

Related: Costco Products You Can't Return

Costco Pharmacy
Charley C./Yelp

Over-the-Counter Medication

Medication can lose effectiveness over time. While it can still be effective after the expiration date printed on the bottle, that depends on a number of factors that are outside of your control, including how it was stored before you bought it. Using medication within its expiration date is just the best and safest policy. Having 400 tablets of almost any kind of OTC medication in the house is not only unnecessary, but could also lead to potentially dangerous situations.  

Costco candy
Costco candy by anjuli_ayer (CC BY-NC-ND)

Junk Food

Huge packages of snacks such as Doritos and M&Ms are always tempting, especially when you make the classic mistake of shopping hungry. Unless items are wrapped in individual packages, though, they tend to go stale before they're finished. The bottom line is: Do you really need 4,000 calories of snacks around? 

School and office accessories on wooden background

School Supplies

A third-grader does not need an entire rainbow of pen colors, and certainly doesn't need six rolls of tape. The selection of school supplies at Costco is small, and packages are large, which makes hitting up the super cheap back-to-school sales a much smarter idea. 

Costco by Lisa Pinehill (CC BY-SA)

Things You've Never Tried Before

Impulse buys at a regular grocery store checkout aisle are fun and pretty inexpensive. If you don't like that new flavor of Snickers, you're out only a buck. But impulse buys at Costco can be much more costly; you could spend $10 or more — sometimes much more — on a 2-quart container of flavored nuts you end up hating. If you see a product you'd like to try, find a smaller, less expensive version of it at a grocery store and upgrade to the bulk size at Costco if you like it.

Related: Insider Secrets for Saving Time and Money at Costco

Costco Eggs
Lisa S./Yelp


If you have a huge school bake sale coming up or your family eats four eggs every day, by all means buy two or three dozen at a time at Costco. Most people don't go through eggs nearly that fast. Don't stink up your house with rotten eggs to save a dollar. 

Cooking Oil

Cooking Oil

Yes, oil can spoil. The large, double packs of huge bottles of vegetable oil at Costco will save you on cost per ounce, but once those bottles are opened, they should be used within a year. Unless you're deep frying often, that may be difficult. Olive oil is even more of a no-no in huge quantities since the expensive extra virgin type loses its character quickly once opened. Opaque containers stored in a cool place help extend shelf life, but it's still best to buy in smaller quantities. 

Related: Foods It's Okay to Skimp On

Kirkland Signature Diapers


Got triplets? Buy your diapers at Costco, by all means. But the huge packages of almost 200 diapers in the smallest sizes means your baby will probably outgrow them before you can use them all. 

Related: The Top Deals at Costco Right Now



Yes, condiments go bad, just like cooking oil. Buying ketchup in big containers — and multipacks — when you use it only occasionally for burgers will lead to expired product in no time. Mayo is even worse, given the danger it poses when it's gone bad. If you're not going to get through a 64-ounce jar of mayonnaise in a few months, don't buy it.

Related: Delicious Recipes That Use Up Those Aging Condiments in the Fridge

Folgers Classic Roast Ground Coffee

Ground Coffee

Pre-ground coffee starts losing its flavor and aroma immediately after opening the seal on the container. If you drink just a cup or two a day, getting through that giant Folgers container before it tastes like you're drinking brown water is going to be difficult. Whole beans that you grind yourself fare better, but even their quality starts going downhill quickly after opening.

Related: I'm a Coffee Snob. This Cheap Coffee Is the Best, IMHO

Costco Lump crab meat
Yulia L./Yelp

Canned Goods

If you've been buying canned goods in bulk at Costco because you assume it's cheaper than a grocery store, think again. They can be 20% to 40% more expensive in bulk. That's because grocery stores have big sales on canned goods regularly, dropping the price significantly. Watch your grocery store's weekly circulars for sales and stock up there instead. Bonus: You'll have way more selection.

Related: Cheap and Easy Recipes From Canned Foods



Maybe beach bunnies who live on the Gulf shore go through multiple bottles of sunscreen each year, but most people do not. Sunscreen loses its effectiveness after three years, so the expiration date on the bottle does matter. You don't want to mess around with ineffective sunscreen and harm your skin. If you're buying sunscreen just for a weeklong cruise, definitely skip the bulk package and buy only what you'll use.

Related: Effective Sunscreens That Will Leave You With Money to Burn



Like canned goods, the regular sales at grocery stores on major brand name cereals often drop the price per ounce much lower than Costco's price. So if your family goes through four boxes of Frosted Flakes every month, you're better off keeping your eyes open for sales than stocking up at the 'Co.

Related: Pie Crust and Other Delicious Uses for Cereal Besides Breakfast



Do you run a bakery? If the answer is no, you probably should not buy leaveners in bulk. Yeast dies, and getting through 2 pounds of it before it does will be a challenge. The same goes for baking powder and baking soda, which lose effectiveness over time. Stick with the smaller packages; they're cheap anyway.


Make sure to sift your flour


Flour comes in 25-pound bags at Costco. You'd need to make a lot of baked goods to get through all that before the sell-by date. Flour does go bad — whole grain and self-rising flour go bad even faster — so unless you have big plans for it, don't buy bulk. 

Related: Common Substitutes for Cooking and Baking Ingredients

Costco Furniture
Costco Furniture by Robert of Fairfax (CC BY-NC-ND)


There are a number of reasons why buying furniture at a warehouse store isn't the best idea. There's not nearly as much selection as at a furniture store, so if you have a limited space or budget it might be difficult to find anything that works at all. There's also no haggling with a salesperson, which means you might not get the best deal. And since most of Costco's furniture is sold only online, you can't even determine how comfortable that couch is before you buy it.

Related: Best Places to Buy Cheap Furniture Online

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Who uses travel agents anymore? In the world of online travel booking, it's possible to get the best deal by planning and booking everything piecemeal yourself as opposed to a vacation package. Sure, it'll take a little more effort, but it'll be custom to your needs and you'll have more money to spend on souvenirs once you get there.

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Kirkland Signature Normandy-Style Vegetable Blend