Although some of the advantages of offline payments are easy to see, there are several reasons why Stripe, and subsequently the Payment app, do not allow for offline payments. Obviously, when wifi or cellular signal is weak or non-existent in remote places, offline payments make sense. If your signal is uncontrollable, you may not want to miss out on a sale. Missing out on a sale means missed revenue, and that's not a desired outcome.
Because payment information must be verified in real time, with several pieces of information, it's imperative that wifi or cellular connectivity is operational so credit cards can be validated. Without these safeguards in place, it is impossible to know if a credit card is fraudulent, stolen or lacks sufficient funds to process the transaction successfully.
There are several reasons that offline payments are not supported by Stripe. First, the risk of fraud, decline and disputed payments increases dramatically. Imagine the following scenario:
A customer approaches your booth, and attempts to pay for several pieces of merchandise with a known stolen credit card. Because the card cannot be verified in real time by the Payment app or Stripe, this customer would be allowed to walk off with the merchandise with the assumption of success in the future.
Without real-time validation of whether the transaction will succeed, it's ultimately too risky to provide offline payments. Lastly, because PCI Compliance and encryption happens after transmission of cardholder information to Stripe, there may be instances where collecting offline payments may be outside the PCI compliance scope. For example, if your phone was stolen at the event without internet connectivity, you may be liable for any credit cards that were stored locally in an app if they were not encrypted.
It's possible, however doubtful. The risks outweigh the rewards, for both payment gateways and merchants. It's true, fraud may be a very small percentage of these transactions, but at the moment, there are no plans to add this functionality.
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