Why payment mismatches happen
OrangeTill generates a QR code for the exact amount of a transaction — so in most cases, the customer simply scans and sends the correct amount automatically. But payment mismatches do occur, for a few reasons:
- The customer entered the amount manually instead of scanning the QR
- Network fees reduced the amount that arrived (some blockchains deduct fees from the sent amount)
- The customer sent from a wallet that doesn't support QR-amount auto-fill
- Human error — they typed the wrong number
- Price movement between when you showed the QR and when they confirmed the transaction
None of these situations are disasters. Each has a clear resolution. Here's how to handle them.
Overpayment: customer sent too much
What happened: The customer sent more than the amount on your QR code — either they entered a higher number manually, or network fees caused an unusual calculation.
What to do: You have two reasonable options. First, ask the customer if they want the $15 back — if they do, send $15 worth of crypto back to their wallet address (or return it in cash). Second, if the amount is small and the customer waves it off ("keep it, tip for the cashier"), you can treat the extra as a tip and note it in your records.
What to record: Note the original sale amount and the amount received. If you kept the extra as a tip, record it as tip income. If you returned it, record the return as an outflow.
Getting the customer's wallet address for a return
To send Bitcoin back to a customer, you need their wallet's receive address. The simplest way: ask them to open their wallet app and show you the QR code for their address. You scan it from your wallet app to send the refund. Alternatively, they can text or email you the address — just verify it matches before sending.
Never try to guess or reconstruct a wallet address. One wrong character sends funds to an unrecoverable place.
Underpayment: customer sent too little
What happened: The customer sent less than the amount owed. This might be an error, or it might be that network fees reduced the arriving amount below the sale price.
What to do: Treat it like receiving less cash than the price. The customer owes the difference. Depending on your relationship and the situation, you can ask them to send the remaining amount in crypto (a second, small transaction), pay the difference in cash, or come back with the remaining amount next time.
What to record: Note the actual amount received and the outstanding balance. Keep a note of the customer's contact information if they're settling later.
Network fee deductions: a specific case
Some blockchain networks (particularly older Ethereum transactions and certain wallet configurations) deduct the network fee from the amount being sent rather than charging it separately. If a customer sends $60 USDC but the network fee is $2, you might receive $58.
This is distinct from the customer underpaying intentionally — it's a technical issue with how they sent the payment. The most graceful solution: if it's a small amount, note the shortfall and let it go. If it's meaningful, explain what happened and ask if they can top it up. Most customers are surprised and happy to make it right.
Encouraging customers to use wallets that charge fees separately (rather than deducting from the sent amount) helps prevent this. Most modern wallets handle fees correctly.
Overpayment (small): Offer to return the extra, or accept as a tip with the customer's agreement. Note it.
Overpayment (significant): Always return it — ask for their wallet address and send back the difference.
Underpayment: Collect the difference in any form (crypto, cash, or deferred). Never release goods for payment you haven't received.
Fee deduction shortfall: Small amounts — let it go. Larger amounts — explain and ask for a top-up.
Payment sent to wrong address
This is the most serious scenario — and it's almost always the customer's error, not yours. If a customer sends crypto to a wallet address that isn't yours (for example, they scanned a QR from the wrong screen, or they typed an address manually and got it wrong), the funds are gone. There is no reversal, no dispute process, no recovery mechanism.
What you can do: If the customer sent to an address they believe is yours but isn't, check your wallet immediately. If you have not received anything, confirm your wallet address is correct in OrangeTill Settings and show the customer. The blockchain explorer linked from your payment history will confirm whether your address received anything.
What you cannot do: Recover funds sent to a wrong address. This is true for everyone — including the world's largest exchanges. Always verify the receiving address before completing a transaction.
Prevention: reducing mismatches before they happen
- Always use OrangeTill's generated QR code — don't ask customers to enter amounts manually if you can avoid it. The QR encodes the amount automatically.
- Show the QR at the right moment — after the total is confirmed, not before. Avoid displaying a QR and then changing the amount.
- For large transactions, verify before releasing goods — check your payment history or the blockchain explorer to confirm the exact amount arrived before handing over significant orders.
- Use Lightning for exact amounts — a Lightning invoice asks for the precise sum, so "$60.00" is paid to the penny. No rounding questions.
Every transaction timestamped and recorded.
OrangeTill's payment history makes it easy to spot mismatches and verify exactly what arrived — with blockchain verification links for every transaction.
See pricing →