You can issue card payment refunds at any time. Depending on your customer’s bank, the refund should show up anywhere between 5-10 business days after the refund is issued. When you refund a charge, the fees you paid to process the charge can not be returned.

See this help article to read about the fees in your country. 

iOS and Android

1. Open the invoice from your Paid invoices folder
2. Tap Transaction history
3. Tap the card payment that you wish to refund
4. Tap Refund payment
5. Tap Yes- issue refund to confirm

Web

1. Open the invoice from your Paid invoices folder
2. Click on View transaction history on the right side of the screen
3. Click on the caret 'v' symbol to the right of the payment you wish to refund, and click on Refund 
4. Click on Refund again to confirm

Helpful Tips

• If your customer paid by card, do not give them a cash refund — this is a common fraud scenario.
• Refunds may appear in the form of a reversal. In the case of a reversal, the original payment will drop off of your customer's bank statement, and a separate credit is not issued.
• Refunds can not be canceled. If you'd like to charge your customer for the amount that you have refunded, you can create a new charge for your customer.