Check your receipt: catching scan errors and overcharges

The sale sign on the shelf and the price in the computer don't always match. When a sale ends, a tag isn't updated, or an item rings up at the wrong price, you get overcharged — and unless you check your receipt, you'll never know. Reading your receipt is one of the simplest money habits a beginner can build, and it takes about twenty seconds.

Why scan errors happen

• A sale started or ended, but the register's price wasn't updated to match the shelf tag.
• The shelf tag is for a similar-but-different size or variety than the item you grabbed.
• A 'buy 2 for $5' or coupon didn't ring up automatically.
• An item scanned twice by accident.

The 20-second habit

1. 1
   Glance before you leave

   In the parking lot or before walking out, scan the receipt for anything that looks higher than you expected.

2. 2
   Watch the sale items especially

   The things you bought because they were on sale are where errors hide — confirm the sale price actually applied.

3. 3
   Check quantities

   Make sure nothing was scanned twice.

4. 4
   Go to customer service if something's off

   Bring the receipt (and, if quick, a photo of the shelf tag). They'll refund the difference.

For online orders too

Digital receipts deserve the same glance. Check that promo codes applied, that you weren't charged for an item that went out of stock, and that shipping matched what you expected. It's easier to fix a billing error the same day than to untangle it weeks later.

The bottom line

Registers make mistakes, and they're rarely in your favor. A quick receipt check catches overcharges from expired sales, wrong tags, and double scans — and the shelf price almost always wins when you point out the gap. Some stores even reward you for catching the error.