Walking into Costco feels like a treasure hunt. It’s easy to get swept up in the magic of warehouse pricing and toss everything into your oversized cart. But let me tell you from years of experience: A deal isn’t a deal if you end up throwing half of it in the trash.
When it comes to certain perishables and household goods, buying in bulk is a trap. The math simply doesn’t work out for the average household, and you end up wasting cash on things that expire before you can use them.
Here are nine items you’re much better off buying in smaller quantities at your local supermarket or drugstore.
9 items to leave on the warehouse shelf
1. Over-the-counter medication: It’s tempting to grab that 1,000-count bottle of ibuprofen or allergy pills for what seems like pennies a dose. But the U.S. Food and Drug Administration warns that expired medical products can become less effective or even risky due to a change in chemical composition. Unless you’re running a clinic, you’ll likely hit that expiration date long before you finish the bottle.
Related: See “5 Expired Medicine Cabinet Staples You Need to Trash Immediately: They’re Dangerous.”
2. Bulk nuts and seeds: Because nuts are packed with healthy, unsaturated fats, they’re highly prone to oxidation. According to Colorado State University Extension, nuts like walnuts and pecans have a particularly short shelf life and will quickly develop a paint-like smell and bitter taste when they go rancid. Buy smaller bags so your snacks actually taste fresh.
3. Sunscreen: You might think you’re getting ahead of summer by buying a three-pack of sunscreen. But those active ingredients break down over time, especially if the bottles are exposed to heat in your car or at the beach. Once a bottle is open, its effectiveness drops. You don’t want to gamble with sunburns just to save a few bucks.
4. Books and movies: Costco’s entertainment table is right in the middle of the store for a reason: it’s a prime impulse-buy trap. While the prices look decent, you can almost always find paperbacks or DVDs cheaper online. Better yet, you can borrow them for absolutely nothing at your local public library.
5. Cooking oils: Believe it or not, oil goes bad. Exposure to light, heat, and air causes cooking oils to oxidize and turn rancid. Buying a gallon of olive oil might seem smart, but if it takes you a year to get through it, you’ll be cooking with spoiled oil by the end. Stick to standard bottles that you can finish in a few months.
6. Beauty products and lotions: That vat of premium body lotion looks like a luxury steal. But every time you open a jar of cream or pump a bottle, you introduce air and bacteria. Over time, the preservatives break down, making the product ineffective or even a breeding ground for germs.
7. Baking essentials: Things like baking powder and active dry yeast lose their effectiveness over time. If you buy a massive brick of yeast, your bread might not rise properly six months down the line. Unless you bake constantly, buy these items in smaller quantities at a regular grocery store.
8. Condiments you use sparingly: Sure, the massive double-pack of ketchup or mayonnaise looks like a steal. But once you break the seal, the clock is ticking. Unless you have a large family or host neighborhood barbecues every weekend, you’ll probably end up throwing away half a bottle when it expires.
9. Fresh produce: Costco’s produce section is gorgeous, but buying three pounds of spinach or a dozen avocados at once is a rookie mistake. Most of us can’t eat that much fresh food before it turns into slime in the crisper drawer. You’ll save money by buying exactly what you need for the week.
How to shop smarter
Before you hand over your membership card at the register, take a second look at your cart. If you can’t realistically finish an item before it goes bad or loses its potency, put it back on the shelf. The true cost of that item includes the portion you end up throwing away.
Related: See “How to Buy in Bulk and Save Money Right Now” and “9 Shopping Mistakes to Avoid at Costco.”