This Is the Worst Mistake You're Making at Costco, According to Experts

Don’t buy more at Costco than you can use without wasting it.

All those bulk buys can be tempting—so much so that it’s easy for a shopper to lose all sense of scale when wandering the aisles at Costco. But if you buy more than you can use, you’re only wasting your money—and effort.

“Buying items in bulk for the sake of saving only works when you will use what you’ve bought,” explains smart shopping expert Trae Bodge. “You’re not doing yourself any favors by buying things that will go to waste.”

Make a Costco shopping list—and stick to it.

One way to avoid the trap of overbuying is to make a list before stepping foot in the store, according to Coupons.com savings expert Lisa Thompson. “It’s so tempting to stroll down the aisles and throw everything into your cart simply because it looks good without thinking about how much food you’re really buying,” she says. “One way to avoid that is to make a list and stick to it as much as possible. If you do want to make an impulse buy or try something new, frozen and canned foods are a safer bet than stocking up on perishables like produce, which are likely to go bad before you can use them all—unless you plan to wash and freeze these items within about a week.”

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Be especially mindful when buying bulk perishables.

"Those big containers of fruits and veggies at Costco are so enticing, right? But before tossing that huge container into your cart, think carefully about how many people you're feeding," Bodge warns. "If it’s just you, or you and one other person, those microgreens will be a soggy mess before you get halfway through the container. Ditto with the grapes or cherry tomatoes that are enough to feed an army."

Julie Ramhold, a consumer analyst with the shopping comparison site DealNews.com, echoes the sentiment. "Purchasing bulk perishables anywhere can be a poor decision if you don't have plans for the items," she says. "Whether purchasing a ton of eggs, milk, or fresh produce, if you end up not using it all and having to throw part of it out, then you're not saving near as much money as you could be."

Ask yourself whether Costco is even really the store you need to be buying such items: "If this happens repeatedly, it could be an indication that you can get away with purchasing smaller amounts from a standard grocery store rather than huge amounts in bulk from a warehouse store," Ramhold says.

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Buying in bulk also drains your available cash.

class="s1">Buying in bulk at Costco also poses another potential hazard for some shoppers: It drains your disposable cash on hand. " Not having disposable money forces you to spend out of your budget and think that you can earn it on your next cutoff or payout, instead of fixating a certain budget control guide," explains Dominic Harper, founder of Debt Bombshell. "Instead of having a spare allotment, which will make you financially stable for a certain month, you end up spending more than the allocation."

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