Watch the checkout screen as you scan, compare the itemized list and prices with what you intend to buy before paying, and check the receipt before leaving. If you spot a discrepancy, ask an attendant to correct it before payment when possible. If you find it afterward, keep the receipt and contact the store promptly. A free item or bonus is not a universal remedy: the rules depend on where you shop and what went wrong.
How to prevent errors while scanning
Confirm each item on the screen
Keep scanned and unscanned items separate enough to track them. After each scan, check that one intended item appeared and that its description and price make sense. This helps catch a duplicate scan, an item that did not register, or a wrong barcode before you continue. Do not assume the machine will detect or flag every mistake.
For produce or other items without an ordinary barcode, follow the register’s instructions and check the selected product, PLU and quantity. Interfaces differ by retailer, so use the prompts shown on the machine rather than assuming every checkout works the same way.
Check sale prices and special offers
Compare sale items, multi-buy offers and other promotions with the store’s advertisement or offer details. The Federal Trade Commission’s 1998 report, Price Check II, notes that promotions may not be in the register system and advises consumers to watch the display and raise errors before paying. Its practical advice is useful, but the report’s scanner-accuracy findings are historical, not a current performance measure. FTC, Price Check II.
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What to check before you pay
Pause before completing payment and compare the on-screen list and quantities with the items you plan to buy. Look for duplicate lines, unfamiliar products, a missed item, a price that differs from the advertised offer, or a total that seems unexpectedly high. Review bag, weight and age-verification prompts instead of approving them automatically.
If something looks wrong, ask the attendant to review it before paying. The exact correction process and what an attendant can change depend on the store. As one retailer-specific example, Walmart’s mobile self-checkout terms tell customers who cannot scan an item to consult an associate so it appears in the digital cart or on the receipt; they also describe prompts such as weighing some produce. Those instructions do not establish a procedure for other retailers. Walmart Mobile Scan & Go terms.
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What to do if an item scans twice or the price is wrong
Before payment
Point out the duplicate, wrong item or price discrepancy to the attendant and ask for the checkout record to be corrected before you pay. For a price mismatch, show the shelf label or advertisement if it is available. Ask about the store’s pricing-error policy, but distinguish a voluntary store promise from a remedy required by local law.
After payment
Check the itemized receipt before leaving when possible. Look for duplicate quantities, unfamiliar products, incorrect prices and missing discounts. If you notice an error later, keep the receipt and promptly contact the customer-service desk or manager with the transaction date, item, amount charged and the correction you are seeking. The FTC advises checking receipts even after leaving the checkout line; a correction may still be possible, though it can take more effort. FTC, Price Check II.
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For a price dispute, preserve the item identity, charged price and advertised or shelf price, along with relevant offer details. A receipt or photo can help document what happened, but neither guarantees a particular legal remedy. Some local rules impose specific evidence and notice requirements.
Does the store have to give you the item free?
There is no single answer for every shopper. A price mismatch, duplicate quantity, wrong barcode and a legitimate prompted charge may be treated differently; applicable law also varies by location. Do not assume every scan error earns a free item or discount. Ask the store to correct the actual charge, then check the official consumer-protection rules for your jurisdiction.
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| Location | What the cited authority says | Important qualification |
|---|---|---|
| Florida | The Florida Department of Agriculture and Consumer Services says a business has no general legal obligation to provide an item free or at a discount because it scanned incorrectly. Some businesses may offer voluntary policies rewarding customers for scanning errors. | This is Florida guidance, not a nationwide rule. Florida Department of Agriculture and Consumer Services. |
| Michigan | For the Scanner Law remedy described by the Michigan Department of Attorney General, a completed transaction must have a receipt identifying the product and charged price, and the shopper must notify the seller within 30 days. The seller may owe the difference plus a bonus of ten times the difference, with a $1 minimum and $5 maximum, within two days of notice. | The page also describes possible court remedies if the specified refund and bonus are not provided. These are Michigan-specific terms; check the current law and official page. Michigan Department of Attorney General. |
| Québec | The Office de la protection du consommateur says its Price Accuracy Policy applies at self-serve checkout. For a qualifying item advertised at $15 or less, the merchant gives it free; if advertised above $15, the merchant sells it at the advertised price with an additional $15 discount. | The policy includes exclusions and distinctions, including certain barcode errors. A shopper may complain to the Office if a merchant refuses to apply it. Office de la protection du consommateur. |
These examples are not interchangeable, and a retailer’s voluntary scanner policy is not the same as a legal entitlement. If the store will not resolve a recurring or apparently systematic problem, contact the relevant local consumer-protection or weights-and-measures authority. Complaint routes depend on where you live; Québec shoppers can contact the Office de la protection du consommateur.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.When a checkout prompt may be a legitimate charge
Not every extra line or prompt is an error. For example, in England, government guidance says retailers must charge at least 10 pence including VAT for qualifying single-use plastic carrier bags and should ensure self-checkouts collect the charge, such as by asking how many bags were used. The rule’s scope and exemptions matter; this is not a rule for the rest of the UK or other countries. UK Department for Environment, Food & Rural Affairs guidance.
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Likewise, retailer-specific prompts may ask you to weigh certain produce or verify age-restricted items. Read the screen and receipt so you can distinguish a required step or charge from a duplicate or incorrect scan.
Quick Recap
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
