Comparing prices
Costco vs Trader Joe’s: How to Find Which Is Cheaper for You
Generic price lists can’t tell you which store is cheaper for your household. Your receipts can. Here’s a fair way to compare.
6 min read · Updated Nov 3, 2026
Why online comparisons don’t settle it
Search for Costco vs Trader Joe’s and you’ll find lists of who’s cheaper on eggs, avocados or coffee. They’re interesting, but they use other people’s baskets, other cities’ prices and a single day’s shelf tags. The answer that matters is narrower: for the things your household buys, in the sizes you buy, which store costs you less?
How the two stores differ
- Costco sells big packs with a membership fee. It tends to win on items you use up quickly, and lose on anything that spoils before you finish it.
- Trader Joe’s sells mostly its own brand in smaller sizes. It tends to win on specialty items and when you only need a little.
- The same product name can be very different packages at each store, which is why the sticker price alone can’t be compared.
Compare like for like
For each item you buy at both stores:
- Find what you paid at each, from your receipts.
- Divide by the size to get a price per ounce, pound or count. Unit prices explained.
- Compare the unit prices, then ask whether you’ll use the big pack before it goes off.
Let your receipts do it
After a few weeks of keeping receipts from both stores, you’ll have real prices for your regular items. Some will clearly be cheaper at one store, and most households end up with a split: a handful of things from Costco, the rest from Trader Joe’s. That split becomes your shopping plan. Here’s how to turn it into one list sorted by store.
Comparing in AisleSplit
In AisleSplit, search any item on the Prices page to see what you paid for it at every store, with each brand side by side and the lowest price marked. When you’ve bought different sizes, it shows which one is the better deal per ounce. Star the store you want to buy it at, and your future lists put it there automatically.
Try it in AisleSplit
One list sorted by store, receipts that type themselves, and the prices you actually paid.
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