7 Costco Items You Shouldn't Buy In Bulk And 7 That You Should

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When it comes to shopping at Costco, bigger isn't always better. The big-box wholesaler has amassed over 133 million members and counting by spreading the idea that bulk purchases lead to lower per-unit costs, fewer shopping trips, and less packaging waste. While the store leverages economies of scale and an ultra-efficient supply chain to keep many of its prices cheap, not every item on its warehouse shelves is a deal.

Most discerning shoppers understand the importance of following a smart shopping strategy before buying in bulk. Select items that will last, that your household will use, and that you'll have enough space for in storage. Many shoppers are even wise on the fact that Costco's treasure hunt-style stocking system drives impulse purchases and overconsumption, which could wipe out some savings. These hidden costs notwithstanding, Costco's super-sized products should mean a higher cost upfront but big savings in the long run, right? The truth is that some wholesale deals are much better than others. To make your dollar go further, consider these seven items you shouldn't buy at Costco, versus seven that will actually save you money.

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A big reason behind Costco's success is Kirkland Signature, the wholesale retailer's much-praised private label that produces everything from frozen food to baked goods to booze. Among the few grocery items that Kirkland doesn't make is breakfast cereal. That leaves Costco's shelves with a minimal selection of brand names, usually some healthier options like Cheerios and Special K balanced out by a couple of sugary choices like Frosted Flakes.

Without a Kirkland option to offer a low-price alternative, shoppers are left with the higher-priced brand names, packaged in two family-sized bags per box. While an unopened box of cereal can last up to a couple years if stored properly, its shelf life decreases considerably after opening. That's why you should think twice about bulk-buying cereal at Costco. Even if you down multiple bowls of Cinnamon Toast Crunch each morning, the savings over single boxes are nonexistent. You're better off going to a regular supermarket that stocks an array of varieties, including private-label options that are often cheaper.

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Purchasing dairy in bulk is risky. If you've ever scooped a spoonful of clumpy sour milk with your cereal, you know what we're talking about. To quell this fear of spoilage, Costco mandates several quality assurance tests beyond those required by the FDA for Grade A milk. Inspectors will send milk back to any supplier that fails to meet the additional audit conditions. The result of all that extra work is milk that regularly lasts beyond the printed expiration date, according to several customer comments on a Costco Reddit thread. That means you won't have to rummage through bulk-sized milk containers to find the best sell-by dates.

Not only is Kirkland Signature milk safe for bulk purchasing, but the per-gallon price is a good deal — around $3.65-$3.89 as of July 2025. That's around 6%-12% cheaper than the nationwide average of $4.03 per gallon. If your household drinks a decent amount of milk, you'll save money shopping at Costco.

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It may be convenient to grab a month's supply of Coca-Cola or Perrier at Costco, but you won't save much money. For example, a 30-can package of Coca-Cola mini sodas costs about 70 cents per can. A box of 10 at Walmart currently sells at about 60 cents a can. Even though that only adds up to a $2 difference at 30 cans, it's disappointing that your Costco membership isn't providing the better deal.

Customers have long bemoaned that soda is among the most overpriced items at Costco. Multiple Costco Reddit threads include comments from members who have noticed the price creeping up, poor packaging that's unable to handle heavy cans, and better deals from competitors like Target and Aldi. Many supermarkets also rely on multi-buy soda promotions to attract deal hunters. Making matters worse for Costco shoppers, Kirkland Signature discontinued its cheaper generic cola years ago after it completely failed with customers. When it comes to soda, the verdict is you're better off buying at a supermarket with more brands and better prices.

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As an ingredient that can go bad from light and oxidation, olive oil is generally considered a grocery item you should never buy in bulk. However, we're making an exception for Costco's Kirkland line, which has some of the best extra-virgin olive oils available at affordable prices. Even professional chefs have recommended the brand for its excellence in cooking and making dressings.

Kirkland's 100% Italian extra-virgin olive oil sells online at $27.99 for a 2-liter bottle. California Olive Ranch's 100% Californian extra-virgin olive oil sells at just under $18 for a half-liter. Walmart sells a 3-liter jug of its Great Value EVOO for under $34, but it's a lower-quality blend that you'll need to guzzle before it goes rancid.

Kirkland's line of 2-liter EVOOs, which also includes an organic variety, is just the right size for those who cook with olive oil daily or several times a week. Olive oil producers recommend using a bottle within three months once opened for the best flavor. To get the most life out of a bulk olive oil purchase, consider transferring it to a dark glass bottle and storing in a cool pantry.

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Considering Kirkland's pedigree for value and quality, its bulk-sized packages of batteries are sadly underwhelming. The brand's 48-pack of AA batteries sells for $16, which is a buck more than Walmart's equivalent Great Value bulk package. Kirkland's offering is slightly better with a 12-year shelf life versus Great Value's 10-year shelf life. However, customers have noted that Kirkland batteries are prone to leaking. Furthermore, the private label only offers two battery sizes — AA and AAA.

Kirkland, which often partners with brand-name suppliers, uses Duracell to make its line of batteries. While that sounds like a major coup, there are differences beyond the packaging, as customers routinely report that the Duracell batteries last longer. Unsurprisingly, Duracell is the only other battery brand available on Costco shelves, and it's a bit more expensive at $20 for a pack of AA batteries. For the ultimate best deal in batteries, we recommend investing in rechargeable batteries, which, unfortunately, are not available at Costco.

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You could call Costco the house that toilet paper built. It's the wholesale retailer's top-selling product, selling over a billion rolls a year. Success like that comes easy when you can sell your toilet paper for nearly 25% less than many competitors.

To compare, Quilted Northern's 2-ply Ultra Soft & Strong costs about $7 at our local Walmart for six mega rolls at 295 sheets per roll. Kirkland Signature's 2-ply Ultra Soft sells for about $25 for 36 rolls of 231 sheets each. That's a lot of math, but it adds up to roughly a $1 savings per 1,000 sheets. Kirkland's standard bath tissue, which comes in a 30-pack of 380 sheets per roll, is even cheaper per square foot.

Those savings, combined with the convenience of stocking up on a non-perishable necessity for a few months, make this a worthwhile bulk purchase. The only drawback to Costco is the lack of high-quality options. Some customers have nitpicked Kirkland's standard bath tissue for being too thin and flimsy, ultimately requiring more paper to get the job done. That said, if your derriere is content with basic toilet paper, then Kirkland bath tissue is a worthy purchase.

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With a shelf life of up to a year, all-purpose flour seems like a good candidate for a bulk purchase. Before you make that investment at Costco, consider how fast it takes your household to get through 20 pounds of flour. Also, factor in that white flour's shelf life decreases to three to six months once opened (if properly stored in an airtight container) and that you're really only saving a couple of bucks on your upfront purchase. The storage hassle and lack of any savings is why food experts say to never buy flour at Costco unless you're running a bakery.

Costco sells its organic all-purpose flour in packages of two 10-pound bags at $20. The equivalent purchase of organic Great Value flour from Walmart will run you about $22. Sure, that makes Costco's a small deal, but you'll pay less than $10 for the same amount if you go for the non-organic Great Value flour. Unless you're constantly baking organic cakes, Costco's multi-pack of flour simply isn't a necessity like toilet paper or milk. Besides, if you run out of flour, you can always substitute blended oats or quinoa in a pinch.

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White rice has an indefinite shelf life when stored properly, making it one of the safest pantry staples to stock up on. Whether you break out the steamer daily or don't want to buy rice for the next decade, Costco's bulk-buy options will ultimately save you money. Kirkland Signature's 25-pound bag of jasmine rice sells for $24, which equates to just under $1 a pound. You'll pay over $6 for a 5-pound bag of Walmart's Great Value jasmine rice and $4 for Kroger's 2-pound bag, with current prices.

Customers attest that Kirkland's colossal rice bags not only meet the quantity requirement, but that the rice also tastes good. Reviews on the product page say that it cooks quickly with a mild floral aroma. Kirkland white rice will hold up to most brand-name competitors, whether you're incorporating it in Italian, Thai, Indian, or any other type of cuisine. The only challenge is finding room to store that extra-large bag: aim for a dark, relatively cool spot that's safe from pests.

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Part of Costco's strategy for offering better deals on bulk sizes is to keep the selection and suppliers limited for each category of item. For laundry detergent, the supplier is currently Henkel, which provides both the All and Kirkland liquid detergents on Costco's shelves. While this has helped ensure quality control, it hasn't made the products any cheaper than what supermarkets offer.

If you're willing to shop around for a different brand, you'll find that an Arm & Hammer 128-load jug goes for about $6 less at Walmart than a 146-load Kirkland jug. Even with fewer loads, the Arm & Hammer is a better deal. You'll get even better bargains if you use budget brands like Xtra and Purex. For those who do feel the quality of Kirkland warrants the price, you may want to stock up on the private label's detergent before it's too late. In early 2025, Henkel announced it will reshape its retail portfolio and stop manufacturing detergent for Costco. Kirkland will either need to find a new supplier or drop its detergent from the shelves.

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It's nice to keep a stock reserve of dish soap, a non-perishable household necessity that always seems to run out at the most inconvenient times. At Costco, you can find good deals on both name-brand and private-label dishwashing liquid. Kirkland Signature's Ultra Shine Liquid Dish Soap is currently sold in a $10 bulk bottle that equates to 11 cents per fluid ounce. While that's slightly more than generic options from Target and Kroger, Kirkland's superior washing power (requiring less liquid per load of dishes) makes it the better investment.

The deals get even better if you opt for the bulk-sized Dawn Platinum, which has a higher concentration of surfactants to better clean greasy dishes. A bulk bottle of Dawn Platinum sells for about 13 cents per fluid ounce at Costco. Meanwhile, you'll pay around 18 cents per fluid ounce for an equivalent amount at a Kroger supermarket. Stocking up on a high-quality dish soap brand is both convenient and cost-effective in the long run. Make room under your sink and top off a smaller bottle whenever you're getting low.

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Canned beans are a pantry staple because you can incorporate them into many meals, and they're usually cheap. Unfortunately, Costco does not sell its canned beans as inexpensively as other places. The wholesale warehouse certainly has a good selection, which includes bulk-sized garbanzo, black, kidney, pinto, and more. But unless you're making enough chili to feed a small army, it's more economical to buy smaller cans at a regular supermarket.

At Costco, a 6-pound, 12-ounce can of Teasdale black beans costs $7.59, or 7 cents an ounce. A more reasonably sized 46-ounce can of Goya black beans sells at the same price per ounce at Kroger. We have to hand it to Costco for technically offering the best deal on Bush's original baked beans, but you have to invest in a 7-pound, 5-ounce gargantuan can to get the 8 cent-per-ounce deal. Canned goods are among the worst things to buy at Costco because many households will never get through all those beans before they go bad. Furthermore, there are no Kirkland canned bean alternatives to compete with the lower-priced generics like Great Value.

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Strawberries and blueberries are some of the best frozen fruits to buy because they're convenient for cooking, last up to a year in the freezer, and are as healthy as their fresh counterparts. They're also more affordable than raw fruit, especially if you invest in bulk-sized bags at Costco. It's difficult to compare to fresh produce, which can vary widely in price based on the season and location, but Costco customers on Reddit claim they have seen frozen fruit at its warehouses selling for less than half the price of fresh produce.

You can purchase a 4-pound bag of Kirkland organic frozen strawberries for approximately $14 (based on current pricing in Southern Nevada). A 2-pound bag of the same product from Target's Good & Gather is going for $10, which is nearly 30% more expensive per pound. Kirkland only offers USDA Organic frozen fruit varieties, which tend to be more expensive than conventional frozen fruit. However, the bulk savings puts it pretty close to regular frozen fruit pricing.

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If caffeine is a standard part of your morning routine, it's tempting to cut back on trips to the store with bulk ground coffee. In terms of immediate cost, you will save a little bit at Costco — Kirkland's Colombian dark roast is about 25% cheaper per pound over comparable options from McCafé and Folgers at Walmart. But before making the purchase, consider that ground coffee gets stale very fast, and Kirkland's comes in 3-pound cans.

Ground coffee can start to lose its taste after two weeks (even sooner for darker roasts). You'll notice that the fresh aroma will turn to a burnt odor while the flavor goes bitter as the grounds oxidize. Unless you have an especially large coffee-drinking household, the quick drop in quality will negate the savings from your bulk purchase. Whole coffee beans, which can last about a month once opened, are better for bulk purchases. Unfortunately, Costco sells its whole bean blend in dual 2-pound packages that are also difficult to consume before they go stale.

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If you're looking for a snack to enjoy in bulk, we recommend mixed nuts over any of the chips, protein bars, or pastries available at Costco — both in terms of nutrition and savings. Kirkland's "Extra Fancy" mix includes almonds, Brazil nuts, cashews, pecans, and macadamia nuts. That's indeed pretty fancy considering other generic labels often overload bags of mixed nuts with cheaper peanuts.

Available in a 2.5-pound bag, Kirkland's mixed nuts sell at roughly 41 cents an ounce. That's just slightly higher than Target's Good & Gather mixed nuts, which include a fair amount of peanuts. Planters Deluxe has a mix that's closer to Kirkland's, yet it sells for 69 cents an ounce at Target.

Mixed nuts are among the few snack foods that are great to buy in volume, especially if you go for the unsalted variety. They have a shelf life of several months, are rich in nutrients, and keep you full longer than many other snack foods. If you prefer your nuts unmixed, Costco also has good deals on pistachios, walnuts, pecans, and more.

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To determine which bulk items from Costco actually save you money versus those that don't, we researched prices on comparable items between the wholesale retailer and traditional supermarkets like Walmart, Target, and Kroger. This meant factoring in product size differences to make the comparisons as apples-to-apples as possible.

Savings was our most important criterion, but consumer ratings, reports, and reviews played a role as well. We placed a greater value on higher-quality products with better longevity. When prices and quality matched up closely, we also considered Costco's membership fees and selection in that category. Finally, we considered our personal experiences shopping and using volume-sized products at Costco and other supermarkets.

All prices referenced are from retailer websites and current as of September 2025. Note: Prices and availability reflect locations in Southern Nevada and may vary in other regions.