There’s an implied promise about buying in bulk: You’ll pay less per unit than if you purchase a smaller amount. That’s part of how Costco makes its profits and offers deals to its members.
But sometimes, that promise is broken. We’ve all had that moment when we looked at a “Family Size” box of cereal or cookies at the grocery store only to find it cost significantly more per ounce than buying a smaller container. It’s hard not to feel deceived when we spot that.
At Costco, the king of bulk purchase deals, some items are more expensive per unit. Others are cheaper or comparably priced but will likely expire before you can finish them. Still others carry a low price but fall short when it comes to quality.
To help you make the best decisions on your next warehouse shopping experience, here’s what we discovered about products you may want to skip at Costco.
1. Laundry Detergent
Prices per ounce for the giant tubs of laundry detergent, dish soap, and other cleaning supplies are usually lower at Costco than at Target, Walmart, or Amazon. However, the stuff has an expiration date.
Unopened detergents have a shelf life of nine to 12 months, and they’re only good for about six months once opened. If you use laundry powder in a high-humidity environment, the number is even lower.
This is fine for large families that wash many clothes, such as a couple with four kids, including two school athletes and a baby in diapers. If you use detergent more slowly, you’ll either waste money or have dirtier clothes.
Parents who need diapers tend to be pressed for time and energy, so it’s tempting to buy them and similar baby supplies during your Costco trip when you buy your other stuff. However, most retailers offer comparable or better prices on diapers:
- Kirkland Brand Diapers (Size 1-2) at Costco: $35.99 for 192 (18 cents per diaper)
- Up & Up Brand Diapers (Size 1 or 2) at Target: $3.79 for 37 (13 cents per diaper)
- Parent’s Choice Diapers (Size 1) at Walmart, $16.47 for 168 (9.8 cents per diaper)
Further, Amazon Family, an offshoot of Amazon Prime, lets you buy the supplies you need for your baby in bulk, giving you a 20% discount on items comparable to Costco’s prices. These come with the added benefit of receiving them regularly without leaving the house.
You won’t find automotive parts or appliance components at Costco, but you can often get air filters for your furnace, ink for your printer, water filters for your fridge, and similar items you need to replace routinely.
You can get these cheaper from the manufacturer, parts clearinghouses, or a local business that services your appliances. If that’s not the case, check subscription purchase options from Amazon before committing to purchasing at Costco.
4. Organic Milk
A three-pack of regular milk is usually a great deal at Costco, but specialized milk is less reliably affordable. As of February 2022, a three-pack of Kirkland Signature 1% organic milk cost $2 more than buying three single gallons at Target.
This same trend often extends to almond milk, soy milk, and similar options beyond 2%, 1%, and whole milk. Add to this how quickly milk goes bad, and you’re usually better off skipping this item in bulk.
5. Cooked and Take-and-Bake Meats
Grocery stores the world over make a lot of their profit from impulse buys. This fact is illustrated by a 2018 study that showed we spend almost $400 a month on impulse purchases.
Those rotisserie chickens, sauced-up spare ribs, and pop-in-the-oven pizzas tempt us because they represent an easy dinner and feel like a good deal. But they’re reliably more expensive than the same option at your local grocery store or superstore.
Costco executives realize a trip to their mammoth store can be exhausting, so they capitalize on the impulse purchases that exhaustion fosters.
Snacks, dried goods, canned soup, and frozen meats are great deals at Costco. However, use caution when evaluating those giant bags and boxes of produce. They’re a staple for the restaurant industry and significant catering events, but ask yourself if your family will eat three heads of Romaine lettuce before the leaves begin to wilt.
As with the detergent we mentioned earlier, the price per unit is only a good deal if you use what you bought before it expires. Unless you reliably use this stuff promptly, only your compost pile will benefit.
Even worse, many produce items at Costco cost more per unit than the equivalent purchase at your local grocery. However, this changes case by case and season by season, so do your research before buying.
7. Single-Item Offerings
Costco makes money and gets savings on bulk purchases. They buy large packages and cut you in on the savings. You should be skeptical of anything Costco tries to sell you in single-item form.
This is not universal, however. Costco car deals and vacation packages are reliably less expensive than you would pay for the exact item from a regular retailer.
If you see a single item offered at Costco, use your phone to compare prices elsewhere. It’s the only way to be sure it’s really a good deal.
Reliable Costco Savings
We’d be remiss if we only told you what not to buy at Costco. Although your experience will vary, as will prices across different seasons and market factors, a few things are reliably less expensive when you buy them here:
- Spices. McCormack-brand spices come in at approximately two-thirds what you would pay at Walmart.
- The Hot Dog Meal. Costco’s head honcho reportedly swore at and threatened the life of an exec who suggested they raise the price of this $1.50 combo meal.
- Breakfast Cereal. Though you’ll need a large enough family to get through it before it goes stale, you’ll pay about 75% of what you’d get it for at Target.
- Gift Cards. These cost between 20% and 30% off face value for things ranging from movie tickets to gym memberships to amusement parks.
- Coffee Pods. Their Kirkland brand pods are high-quality and sell for just over half what you’d pay at Walmart for a comparable brand.
- Gas. The price at the pump is usually a few cents lower than you’ll find elsewhere, and their cash-back programs add up to as much at 6% combined further savings between reduced price and rebates.
- Medication. Check this case by case because it isn’t guaranteed, but in many cases, you can get a price lower than what’s available with many insurance plans.
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