Zero Authorization
What Is a Zero Authorization? Definition and How It Works
Definition
A zero authorization (also called a zero-dollar auth or card verification request) is a payment card authorisation submitted for a transaction amount of zero dollars or zero currency units. Its purpose is to verify that a card is valid, active, and usable before charging it, without actually moving any funds. Zero authorizations are used during card-on-file setup, free trial onboarding, and account verification flows where the card must be confirmed before a future charge.
How it works
A zero authorization submits a standard card authorisation request to the issuer with an amount of $0.00. The issuer validates the card number, expiry date, and CVV (if submitted), confirms the account is open and in good standing, and returns an authorisation response. An approval confirms the card is valid and the issuer will accept future transactions; a decline indicates a problem with the card (invalid number, closed account, fraudulent card) before any money changes hands.
Zero authorizations do not create a hold on the cardholder's account and do not require capture or settlement: there is no amount to settle. They are a verification-only action. The merchant receives an authorisation code confirming card validity, which can be stored alongside the tokenised card credential as evidence that the card was validated at the time of storage.
Not all issuers support zero-dollar authorizations. Some issuers decline zero-amount requests because their systems do not recognise a zero-dollar auth as a valid transaction type. In these cases, merchants sometimes substitute a $0.01 or $1.00 authorisation that is immediately voided after receiving the approval response. Card scheme rules define how zero-dollar and small-amount verification transactions should be submitted and handled.
The specific use case determines the correct transaction type. For verifying a card before adding it to a wallet or storing it for future use, Visa and Mastercard define specific Account Verification transaction type codes that should be used rather than a standard purchase authorisation for zero dollars. Using the correct transaction type avoids scheme rule violations and ensures correct issuer handling.
Why it matters
Zero authorizations prevent failed charges on stored credentials by verifying card validity before any billing cycle. A subscription service that adds a card to file during a free trial and then attempts to charge it at the end of the trial period benefits from early validation: cards that are invalid, closed, or subject to issuer restrictions are identified during the trial rather than at the point of first charge.
Zero authorizations also support fraud prevention in card-on-file flows. Fraudsters attempting to add stolen cards to a platform to test their validity will trigger a zero-dollar auth during card addition. If the issuer returns a decline or flags the card as compromised, the fraudulent card is rejected before it can be used for subsequent charges.
Compliance with scheme rules for card verification is important. Misusing standard purchase authorisation codes for zero-dollar card verification can trigger scheme rule violations and issuer complaints. Using the designated account verification transaction type ensures the issuer and scheme process the request correctly and that it does not create unintended authorisation holds or reporting anomalies.
With PXP
PXP supports zero-value account verification to confirm a card is valid before storing or billing it. Talk to our team about how PXP can support your account verification.
Frequently asked questions
What is the difference between a zero authorization and a pre-authorization?
A pre-authorization (pre-auth) is an authorisation for an estimated transaction amount that creates a hold on the cardholder's available credit or account balance, intended to be followed by a capture for the final amount. A zero authorization is a verification-only request with no amount and no hold, used purely to confirm that a card is valid and usable. Pre-auths are used for hotel check-ins and car rentals where the final charge is unknown; zero auths are used for card validation at storage time.
Why do some issuers decline zero-dollar authorizations?
Some issuer processing systems were not designed to handle zero-amount transactions, which can appear as a system error or an invalid request in legacy authorisation processing frameworks. These issuers decline zero-dollar auths not because the card is invalid, but because their systems reject the transaction type. Merchants facing this issue typically substitute a $0.01 or $1.00 authorisation immediately voided after receiving an approval, though this approach requires careful handling to avoid charges appearing on cardholder statements.
Does a zero authorization appear on a cardholder's statement?
A properly submitted zero-dollar authorization or account verification request should not appear on the cardholder's statement and should not create a visible hold on their account balance. Because there is no amount, there is nothing to display or hold. Some payment apps and bank apps do show authorisation activity including zero-amount verifications as informational entries, but these should clear without any balance impact. A $0.01 verification charge that is voided may briefly appear and then disappear, which can occasionally cause cardholder confusion.
Revolutionize your business with PXP
Take complete control of your commerce and payments with one platform.
Get Started