Mastercard 4871 — Chip/PIN Liability Shift (Lost/Stolen): What It Is and How to Respond

Mastercard 4871 is the PIN variant of the chip liability shift. It applies when a chip card was used at a chip terminal (satisfying the EMV requirement that prevents MC 4870), but the terminal required a signature instead of a PIN — and the card was used by someone who had lost or stolen it.

The reasoning: if the terminal had supported PIN, the fraudster wouldn't have been able to use the card. By accepting chip-and-sign on a PIN-capable card, the merchant removed the security layer that would have stopped the fraud. Liability shifts to the merchant who didn't require PIN.

Common reasons you received this dispute

1. 1Chip terminal required signature rather than PIN for a PIN-capable card
2. 2Terminal was configured to bypass PIN entry for a card that required it
3. 3PIN was bypassed as a "customer convenience" setting in the terminal configuration
4. 4Card was used in a market where PIN is standard but terminal only supported chip-and-sign

Can you win this dispute?

Evidence checklist

1. ✅ Required

   Terminal configuration showing PIN capability: Documentation confirming your terminal supports PIN entry. This is the foundational requirement — without it, there is no defence.

2. ✅ Required

   Transaction log showing PIN was used (PIN verification code in log): Your terminal's detailed log for the disputed transaction, showing a PIN verification method code that confirms PIN was entered and verified — not bypassed or replaced with signature.

3. ⭐ Strongly recommended

   Acquirer certificate of PIN compliance: A letter or certificate from your payment processor confirming that your terminal is certified for PIN processing at your location.

4. ⭐ Strongly recommended

   Terminal receipt showing PIN used indicator: The receipt from the disputed transaction showing “PIN VERIFIED” or equivalent — not “SIGNATURE” or “NO CVM.”

How to write your response

Key deadlines

How to prevent this chargeback

1. 1

   Enable PIN for all chip transactions where the card supports it: Never bypass PIN for convenience. PIN is the security layer that prevents lost/stolen card fraud — removing it transfers liability entirely to you.

2. 2

   For international merchants: PIN is standard in most markets: A chip-and-sign-only terminal is increasingly non-compliant globally. If you operate in markets where PIN is the norm, chip-and-sign leaves you exposed to 4871 chargebacks on every lost/stolen fraud transaction.

3. 3

   Work with your acquirer to ensure your terminal firmware supports PIN bypass prevention: Some terminal configurations allow cashiers to skip PIN — close this option. A terminal that “can” do PIN but allows bypass still exposes you to liability.

4. 4

   Audit terminal configurations after software updates: PIN settings can sometimes be reset or overridden during firmware updates. Schedule a configuration audit after every terminal software update to confirm PIN requirements remain enforced.

Frequently asked questions

Related reason codes