Why it happens
- The merchant was listed in a Mastercard program for questionable or fraudulent activity.
- The merchant processed transactions it was not allowed to process.
Mastercard4849Fraud
Questionable Merchant Activity
Mastercard has identified the merchant in one of its compliance or fraud programs, and the issuer disputes transactions covered by that finding.
What to send to fight it
- Proof the transaction was not covered by the Mastercard program finding, provided through the acquirer.
- Proof a refund or reversal was already processed.
- Records showing the merchant was not in the program at the time of the transaction.
How to prevent it
- Keep fraud and dispute ratios low and track them every month.
- Follow your acquirer’s rules on what you are allowed to sell.
Summaries written by NoChurn from the networks’ public rules and processor documentation. Networks update their rules and deadlines depend on your processor: check its documentation before you respond.
Other Mastercard codes
- 4808Authorization-related Chargeback
- 4837No Cardholder Authorization
- 4840Fraudulent Processing of Transactions
- 4863Cardholder Does Not Recognize—Potential Fraud
- 4870Chip Liability Shift
- 4871Chip/PIN Liability Shift
- 4834Point-of-Interaction Error
- 4831Transaction Amount Differs
- 4842Late Presentment
- 4846Correct Transaction Currency Code Not Provided
- 4853Cardholder Dispute
- 4854Cardholder Dispute—Not Elsewhere Classified (U.S. Region Only)
- 4841Cancelled Recurring or Digital Goods Transactions
- 4855Goods or Services Not Provided
- 4859Addendum, No-show, or ATM Dispute
- 4860Credit Not Processed
- 4999Domestic Chargeback Dispute (Europe Region Only)
Sources (1)
- Mastercard Chargeback Guide, Merchant Edition (19 May 2026) · checked 2026-11-09
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