Mastercard reason code 4870
Mastercard 4870: Chip Liability Shift
What the cardholder is claiming
The cardholder says a counterfeit card was used, and the issuer says the loss is yours because your card-present terminal did not read the EMV chip. It was swiped on the magnetic stripe or fell back to stripe on a chip card, so liability shifted from the issuer to you.
The evidence that actually wins
Bank analysts skim responses in minutes against a checklist for this exact code. Lead with the strongest fact; never make them dig.
- ✓EMV data in the authorization record proving the transaction was actually chip-read (the DE55 cryptogram data)
- ✓Proof the terminal was a certified hybrid chip-capable device on the transaction date
- ✓Authorization records showing a technical fallback initiated by the card, with the issuer approving the fallback transaction anyway
- ✓Card service-code data showing the card was not a hybrid chip card, which voids the liability shift entirely
- ✓Proof the transaction was card-not-present, since 4870 is a card-present code and is misfiled against e-commerce sales
The honest read
This code exists specifically to move counterfeit-card losses onto merchants running old hardware, so if a counterfeit card was swiped on a non-chip terminal, you are the designated loser and there is usually nothing to argue. The winnable cases are technicalities: the transaction was actually chip-read, the card had no chip to begin with, or the code was misfiled against a card-not-present sale. If your terminal genuinely cannot read chips, put the money into new hardware instead of dispute responses, because this loss repeats until the terminal changes.
Nobody can promise you a win; the cardholder's bank decides. What you control is submitting the strongest complete case your records support, on time. Our plain-language guarantees say exactly what that means.
Fighting a 4870 right now?
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