Zero-value pre-authorization (zero-auth)

Zero-value pre-authorization allows you to verify that a customer’s card is valid and active without holding or charging any funds.

This step is typically used when setting up card-on-file or recurring payments to ensure the card can be successfully charged later.

A zero-value authorization does not guarantee future payment success, as available funds, limits, and card status may change after verification. It only confirms that the card is valid at the time of the check.

Why use zero-value pre-authorization instead of charging immediately?

• You are not ready to take payment yet, for example when a customer only saves their card details or signs up for a free trial.
• You want to avoid visible test charges; unlike low-amount pre-authorizations, zero-auth does not create pending transactions or temporary holds on the customer’s account.
• You are establishing a stored-credential relationship, for example when the customer chooses to store their card details as part of their profile at your website.
• You want a friction-free setup flow, verifying the card in advance and charging only when service starts or when the customer initiates payment.

Additional notes

Always ensure you obtain the customer’s explicit consent before storing card credentials for future use. When you later charge the stored card, mark subsequent transactions correctly as card-on-file or recurring payments, according to the way the initial transaction was performed.