Chargeback Reason Code

Mastercard Chargeback Reason Code 4812: Account Number Not On File

General Information about Reason Codes

In 2016, Mastercard chargeback reason codes were condensed and consolidated, in a restructuring that resembled Visa Claims Resolution. Prior to this, Mastercardā€™s list of reason codes was long, convoluted, and confusing; now there are fewer than ten different reason codes relevant to most merchants. All the old reasons are still there, but theyā€™ve been grouped under more comprehensive ā€œumbrellaā€ codes.

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Mastercard Chargeback Reason Code 4812: Account Number Not On File

What is Mastercard Chargeback Reason Code 4812?

The Mastercard chargeback reason code 4812 refers to a transaction where the account number is not on file. This suggests that the issuer has no record of the account number used for the payment, prompting a chargeback. As a result, the issuer believes it is not responsible for the transaction and processes a chargeback.

This code falls under the ā€œNo Authorizationā€ category of chargebacks. It is often an error on the merchantā€™s end. However, fraudulent practices may cause the issuer to process a chargeback when the account number is not in its records.

An example is processing a transaction for account X. The transaction is authorized. However, the issuer cannot find account X in its system.

The issuer will process a chargeback with this reason code. It is up to you to verify whether this claim is true or false.

Refer to Mastercard chargeback reason code 4808, as code 4812 might become obsolete. That is because a transaction without a valid account number with the issuer is deemed unauthorized. Nevertheless, you may still receive chargebacks with the code until the issuer removes it completely.

You can represent the claimed ā€œunauthorizedā€ transaction and reverse the chargeback if you consider the payment valid. However, that requires understanding why it happened. The latter will guide you on what evidence to present in your second presentment.

Why Did it Happen?

The Mastercard chargeback reason code 4812 occurs when an issuer refutes a transaction because it does not have the account number in its records. This occurrence is unusual since the lack of a valid account number will generate an error during authorization. That means the transaction will not go through.

Nonetheless, the following factors can trigger this chargeback:

  • Usage of a retired account number.
  • Offline transaction authorization, especially if a chip transaction wasn't appropriately authorized online.
  • The account number was missing from the Electronic Warning Bulletin during the payment.

Other causes that may bypass authorization and cause this chargeback include the following:

  • Manual entry of the transaction details, which might reduce errors.
  • Forced submissions that bypass buyer authorization.
  • The account for the payment was retired before the transaction date.
  • The use of fake credit card numbers at checkout (purchase). In this case, your systems failed to identify the error before processing. This case is often linked to fraud and scams.
  • Software glitches or cyberattacks corrupting transaction data. Again, this case is often linked to online fraud.

These issues underscore the importance of adhering to proper authorization protocols during transactions. A glitch in your verification system may also cause an invalid account number to go through. You have 45 days to respond to this chargeback if you believe it is invalid.

How to Fight Mastercard Chargeback Reason Code 4812: Account Number Not On File

Fighting this chargeback involves proving that you issued a refund (if the error was on your end) or that the claim is false.

To challenge this chargeback you can:

  • Provide evidence of appropriate transaction authorization. Required data records include: ACCOUNT NOT CLOSED, AUTH MMDDYY, or PREAUTH MMDDYY.Ā 

Use PREAUTH if the transaction was pre-authorized and AUTH if it was not. Also, provide the approval date of the disputed payment using the MMDDYY format.

  • Provide evidence of submitting the transaction within the allotted time frame. This is usually within seven days of transaction authorization.
  • Showcase supporting documents that validate the account number at the transaction time.
  • Highlight any refunds issued to the issuer upon recognizing an error.
  • Present the transaction approval code to back your claims.
  • Indicate any violations of the issuer's chargeback requirements, such as a chargeback initiated beyond 120 days from the transaction.
  • Provide evidence that the transaction was approved online by the issuer or offline by the chip.
  • Show proof that a legitimate account number was used to authorize the transaction at the time of payment.

Cases involving fraud or cyberattacks may be challenging to represent and reverse the chargeback. Your insurance provider might provide coverage against digital theft. Hence, you donā€™t need to represent the chargeback with the issuer.

How to prevent Mastercard Chargeback Reason Code 4812: Account Number Not On File

Preventing this Mastercard chargeback boils down to acquiring adequate authorization before processing a transaction. That involves verifying the account holder and comparing it with those on the warning bulletin.

To mitigate the risk of this chargeback, consider the following:

  • Ensure proper transaction authorization.
  • Confirm authorization before processing.
  • Refrain from overriding issuer-declined transactions.
  • Ensure that terminals are chip-compliant to obtain proper permission for transactions.
  • Ensure your payment terminals are EMV-enabled.
  • Regularly update terminal software to guard against malfunctions.
  • Handle soft-declined transactions with caution.
  • Submit transactions within seven days of the authorization date.
  • Implement robust online security measures to thwart hacking.
  • Avoid manual data entry to minimize errors.
  • Train staff to recognize potential triggers for this chargeback, responding appropriately.
  • Ensure you have records for any emergency cases as evidence if a chargeback occurs.


Important Notice!

Refer to Mastercard chargeback reason code 4808, as code 4812 might become obsolete. However, the principles and practices mentioned remain relevant for any "account number not on file" scenario.


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