# Card Verification

Card verification is a strong first-line defense against potentially fraudulent cards. It ensures that the credit card number provided is associated with a valid, open account and can be stored in the Vault without actually billing the customer for a charge. This is ideally useful when you have a signup flow with a credit card, where the you collect the cardholder details during signup and allowing you to charge the card when necessary.

# How it works

The OMPay gateway verifies credit cards by running either a $0 or $1 authorization and then automatically voiding it. For most processors and card brands, transactions are initially tried with a $0 authorization. If $0 authorizations are not supported, a $1 authorization (or the equivalent in the submitted processing currency) will be performed automatically.

In any instance where a $1 authorization returns a successful result, we immediately follow up with an automatic void request to ensure that the transaction does not settle and that it disappears from the cardholder's statement as soon as possible.

# Verifying a card

To verify a card, simply setup a payment request with the transaction.amount.total field set to 0

Refer to Create Payment

# Verifying stored cards

Due to PCI compliance restrictions, we never store your customer’s CVV. You’ll need to collect this from them again before re-verifying a card via the API.