Home Items You Should Never Buy At Costco

A woman asked her husband if he would please stop at Costco on his lunch break and pick up some paper towels for the party. The man, though frustrated, agreed nonetheless. He came home and was inexplicably angry, slamming down the paper towels. The wife asked him, "What on earth has gotten you so upset?" He answered, "I went to Costco for paper towels, and bought the Cleveland Browns and a helicopter!" 

Most of us have had a similar experience shopping at Costco, and while it's great for many home products (especially if you have a large family), there are still some items you should never buy from them (especially in bulk). We've taken the time to research this for you, and put together a list to save you the pain of learning an expensive lesson. After all, there's nothing worse than buying something you end up not using — except for maybe buying way too much of it.

But before we get into these specific items, let's consult some interesting facts through Statista about the warehouse giant. Costco opened in 1983 in Seattle, Washington and today they are in third place for the biggest retailer on the globe. However, MBA Skool says that, in 2022, Costco slipped by revenue to fourth place, with CVS Pharmacy in third place, behind Amazon in second, and Walmart in first. CVS saw $292 billion in revenue, while Costco saw $210 billion, Amazon recorded $469 billion, and Walmart had $572 billion. Regardless, Costco is definitely in the top five retailers in the world, and they have more than 90.3 million members worldwide. So, without further ado, here are some items you should never buy at Costco.

Diapers

Natural Baby Life does a comparison on prices of diapers from Costco with some other major suppliers, such Target and Walmart, and overall found that, for house brands, they're not really cheaper. It's certainly no wonder that parents are keenly interested in the topic of diapers, as apparently the average parent changes more than 2,500 diapers before their little bundles of joy even turn one! In their comparison, Costco's biggest rival, Walmart, actually had the lowest consistent price of their house brand at about $0.10 a diaper. Huggies size 1 diapers are about $0.21 a diaper, and Kirkland Signature (Costco's house brand) size 1 diapers were $0.16 a diaper. The fact is, if you're trying to save money, even Target's house brand, Up & Up creams Kirkland at the excellent price of $0.11 a diaper. Others were compared, and most other retailers' house branded diapers beat Costco's Kirkland Signature prices. Surprised? There's more.

Passionate Penny Pincher also did a price comparison between Costco, Sam's Club, and Amazon. In their results, they found that Amazon had the best prices with their house brand Mama Bear diapers at $0.12 a diaper. Sam's Club came in second with house brand Member's Mark Premium diapers at $0.13 a diaper. Costco's Kirkland Signature came in at $0.15 cents a diaper. Interestingly, they also compared prices on baby wipes for these three house brands and found that all three of them broke down to the same price of $0.02 a wipe. Now, it still pays to shop around, of course — since most of these retailers are close in prices, sales or coupons can make all the difference.

Books

It can be tempting to buy books when you see a big table of great titles that you know are priced lower than at bookstores, but you should consider refraining, according to several sources, including Wirecutter. This informative source offers multiple different ways to read more for less money, including online audiobook subscriptions, investing in an e-reader and purchasing less expensive e-books, using an online book trading club, and buying used books for much less on various websites — just to name a few! But if money isn't your only motive, the book aficionado who carefully wrote this piece also informs us how important it is to purchase new books at bookstores — at least when we can. Doing this actually helps authors be able to keep writing and getting paid for it, as well as being able to do book signing tours, marketing and advertising, and cover editing and design costs, etc. If you love buying new books, consider supporting your local bookstore. They're becoming a dying breed, and they're essential in supporting authors.

Kirkland bottled water

Something you may or may not know about are the major problems Costco has had with their bottled water, according to Eat This, Not That!. About a year ago, Costco experienced a problem with their water supply and placed limits on the amount of bottled water customers could buy. This article additionally discussed people were complaining about their Kirkland brand bottled water having a terrible smell and taste. This complaint was widespread, with some people saying the water smelled like a fish tank or lake water, and had a chemical taste. Countless others shared their similar experiences on Facebook, stemming from a post by Sara Miller. One thing that stood out is the fact that most of these people were normally fans of Kirkland bottled water, but clearly something different was going on.

Consumer Reports did a report on the quality of water from many different brands, and revealed that Costco's Kirkland sources its water from the Niagara brand. Looking up the report for Niagara from there, it's found their system includes adding minerals, and they use a process for disinfecting the water with ozone just prior to bottling it. This can cause an unpleasant taste that may affect some water and not others, and one that some people may notice while others do not. Just to be safe, you might want to skip the Kirkland bottled water. Interestingly, Dmcoffee.blog reveals that Niagara is also the source for multiple other retailers' house brands, including Walmart, Safeway, and Sam's Club. It's important to note that most of the time there are no problems, but there can be inconsistencies.

Kirkland Liquid Gel Dishwasher Detergent

Consumer Reports issued a list of product ratings from Costco, with certain ones making the grade, while others, not so much. There were several products tested, from car batteries and toilet paper, to laundry detergent and mattresses. One of the worst performers was Kirkland Signature Liquid Gel Dishwasher Detergent, which scored just 34. The report stated the detergent could not keep up with cleaning dishes or pots and pans, nor could it fight or resist water spots. It suggested Kirkland Signature Dishwasher Pacs instead, but this label did not make their list of recommended picks, either. To see specifics about the rating, you must be a member, but we know that this is a highly respected company that tests products in several different categories for multiple aspects of each one. Therefore, it's a pretty safe bet this is one product you might want to skip at Costco.

Toilet paper and paper towels

Believe it or not, toilet paper and paper towels are on the list. Rachel Teodoro says she has a love/hate relationship with Costco, that's actually mostly hate — mainly because they make you think you're getting a great deal, when you're really not. One piece of advice she shares is to make sure you know what the prices are at other stores before you go shopping at Costco. 

Let's return to the example of toilet paper and paper towels. The brand of toilet paper compared was Quilted Northern. At Costco, they sell a 30-pack for $19.99, which works out to about $0.67 a roll. Winco sells a 24-pack for $13.47, which works out to about $0.56 a roll — a fairly significant difference. Brawny paper towels were also compared, with Costco selling a 15-pack of mega rolls for $19.99, making each roll come to $1.33. Winco sold 8 mega rolls for $6.97, making each roll come to just $0.87. That's a HUGE difference, and one that's not in Costco's favor.

For better options, we consult the The Krazy Coupon Lady, who has some alarming information, like the fact that all stores are not created equal when it comes to roll size. In other words, a 9-pack of Charmin mega rolls at Walmart is not necessarily same size as a 9-pack of Charmin mega rolls through Amazon. These are things negotiated between the manufacturer and the retailer, behind the scenes, and aren't public knowledge. The square footage can vary by store up to 25%! If that shocks you, join the club. The advice? Always determine price per square foot when comparing prices on toilet paper. Additionally, you can download the free Krazy Coupon Lady App, which will help you always find the best deals on toilet paper and paper towels.

Breads and pastries

First of all, we all know bread and pastries will eventually get stale, go bad, and become inedible, so it stands to reason this is something you should not buy more of than you can eat in a reasonable amount of time. But, is that the only reason we've included bread on this list? Of course not! Reader's Digest says that most of Costco's bread products are low in fiber, high in calories, and consist of no nutritional value. There are a few exceptions, such as whole grain breads, but generally Costco's bread and pastry items are considered unhealthy. Yes, the pastries look delicious and are tempting as can be, but will you really be able to eat all that bread and sugar before it gets stale?

GOBankingRates talks about what groceries you should and shouldn't buy at Costco, and bread and pastries are at the top of the "don't buy" list. It explains that, although you can freeze bread, when it comes to pastries, you might not enjoy the flavors or textures as much after freezing them. Additionally, you'll need to wrap them individually and tightly with plastic wrap. Keep in mind that bread takes up a lot of freezer space, as well. We know there are some bread aficionados out there that have been looking for the best price on Ezekiel Bread, and The Krazy Coupon Lady doesn't disappoint with her information. A price comparison reveals that, believe it or not, the popular bread is priced best at Trader Joe's, at $0.15 per ounce. Incidentally, Trader Joe's is a great place to find (actually) healthy bread, too.

The Costco rotisserie chicken

This is an extremely disturbing situation of an item that likely would not have made this list until quite recently, when CNN reported Costco is being sued for animal mistreatment. The story goes, in 2019, Costco spent $450 million dollars to open a poultry processing plant in Nebraska in order to be able to supply their member demand for rotisserie chickens. Staying true to their decade-long cost of $4.99 each, amidst today's inflation, they stood out among competitors. However, in this case, it may cost them. Allegations of cruelty had been previously made by an animal rights group, and undercover footage had been shot by Mercy for Animals as part of an exposé on Costco in 2021. Now, two shareholders have filed a lawsuit against Costco alleging their mistreatment of the chickens, and of their willful negligence of the situation constituting a breakage of their fiduciary duties. The lawsuit says Costco executives were aware of the mistreatment, yet choose to ignore it. Costco has defended themselves, saying they follow standards set by the National Chicken Council.

Consumer Reports offers some additional information about the video filmed secretly at one of Costco's warehouses by Mercy for Animals. The footage shows hurt, swollen, and deformed birds being kept in a dark, windowless warehouse. The lawsuit stated these birds are left to slowly starve, or die of neglect or untreated illnesses. Since then, pressure has built against Costco for their refusal to sign an agreement that over 200 other businesses have signed, called the Better Chicken Commitment. Incidentally, Bobby Parrish of FlavCity says Costco's rotisserie chickens are extremely unhealthy due to them being poor quality and full of sugar, MSG, preservatives, and chemicals. These are pretty compelling reasons to skip Costco chicken altogether.

Eggs

While it just makes sense that eggs are on the list for the same reason as the rotisserie chickens, they actually make the list for other reasons as well. Back to FlavCity, we're told even Costco's organic eggs are low quality and that people should purchase pasture raised chicken eggs instead. The article points out that the term organic doesn't mean a whole lot when it comes to the health or welfare of the animals, due to the fact that the animals can be caged and treated inhumanely, and still technically be considered organic if they're fed organic corn or grain. Since we're now aware of how Costco cares for their chickens, it makes you question their eggs, too. (Although it is not known for sure whether their eggs are self-sourced.)

For a little further insight, we go straight to the horse's mouth — so to speak — and consult the U.S. Department of Agriculture. The post discusses how consumers are overwhelmed with choices for differently rated eggs (and other agricultural products) in today's marketplace, ultimately leading to more confusion than educated purchasing. Yet, big changes are apparently in the works where eggs are concerned, due to growing commitments by consumers and businesses alike to healthier, cage-free conditions. Apparently, a large number of noteworthy institutional egg purchasers have announced their commitments to buy eggs solely from cage-free productions within 10 years time (the article was published in 2017). This is big news, since, at the time of the article's publication, only 10% of the U.S. supply is from chickens raised in cage-free conditions. In the meantime, do your research — and skip the eggs from Costco.

Soda

According to a piece in Reader's Digest on secrets revealed by Costco employees, one of their key pieces of advice is to skip buying soda at the retailer. While they state there's nothing wrong with it and it can be a decent deal, there are typically better deals elsewhere. We all know soda is one of those things that seems to spread its sales prices around pretty well, alternating from store to store effectively, week by week. Therefore, it pays to check for the best prices when you're ready to shop. Another great website to check out for finding great deals on soda is called the Passionate Penny Pincher, or you can check out Flipp and download their app. Additionally, Reference did a similar article that advises consumers of the same tip regarding soda, adding that, at Costco, soda is known to be one of the least purchased items. This fact means soda rarely ever goes on sale at Costco, meaning you can almost always find a better deal elsewhere. 

Interestingly, they also mention another Costco secret you might not know. Have you ever wondered why it seems like employees just put things wherever they can find shelf space? It's done like that on purpose. Employees move things around and watch what sells and where, all the while knowing the more you have to walk around and look for the items you came for, the more items you see that you might buy on impulse. There's a method to that madness, after all! What does that have to do with soda? Absolutely nothing. Sorry, we digress...

Spices

Last but not least, ILoveCostco (ironically) explains why purchasing spices from Costco is not a good idea. The main reason has to do with the fact that, although you may not think to check expiration dates on spices, they do in fact go bad. And when you buy them in bulk, they nearly always expire before you can use them. It's important to note that the expiration date on newly-purchased spices is typically a few years out; however, the average person still won't use the entire container before they expire.

Consumer Reports has another shocking reason to pay attention to spices from Costco, and other retailers, as well. Apparently, after testing 15 different types of dried herbs and spices and 126 products from major retailers of both house and national brands, high levels of potentially dangerous heavy metals were found. These were things like arsenic, cadmium, and lead, and were found in almost a third of those tested. The levels are high enough to cause health problems for children in particular, but adults as well, when consumed regularly. Unfortunately, the advice here is to limit your intake of store-bought spices in general, unless you carefully research the brand and its ingredients first.