How to check your receipt for errors in 30 seconds
Short answer
Before you leave the store, check five things on your receipt: the same item appearing twice, sale prices that didn't apply, coupons that are missing, weighed items with the wrong weight, and voided items that still show a charge. Then make sure the total matches your card slip.
Skip the hassle next time. Scan your receipt with Dupe Detective before you leave the store. It takes a few seconds, and a double charge caught at the register is fixed on the spot.
It's worth the 30 seconds. In a fall 2025 University at Buffalo survey, one in four U.S. shoppers said they are overcharged at checkout at least once a month. More checkout overcharge statistics.
The checklist
- Repeated lines. The same item and price on two lines usually means it was scanned twice. These are easy to miss when other items sit between them.
- Sale prices. Look for the shelf price on items you picked because of a sale. Loyalty-card discounts usually print as a separate line under the item.
- Coupons. Each coupon you handed over should appear as a negative amount.
- Weighed items. Produce and deli lines show a weight and price per pound. A bag of apples shouldn't weigh 4 pounds.
- Voids. If the cashier voided something, there should be a matching negative line.
Then check the total
The item count near the bottom should match what's in your bags. The total should match the card slip or the charge on your banking app.
Found a mistake?
Go to the register or customer service before you leave. It's much faster than calling later. If you're already home, read how to get a refund for a grocery store overcharge.
Dupe Detective does step 1 for you: scan the receipt with your iPhone and any repeated item is highlighted.