Complete Guide to Chargeback Reason Codes (Visa, Mastercard, Amex, Discover)

What are chargeback reason codes and why do they matter?

A chargeback reason code is a numeric or alphanumeric code assigned by the card network — Visa, Mastercard, American Express, or Discover — when a cardholder disputes a transaction. The code identifies the specific reason for the dispute: fraud, item not received, processing error, subscription cancellation, and dozens of other categories. Each code maps to a distinct set of evidence requirements and rules that determine who wins.

Reason codes matter because the evidence that wins one code type will fail another. A Visa 10.4 fraud dispute requires proof the cardholder authorised the transaction — delivery confirmation alone won't win it. A Mastercard 4853 “goods not as described” dispute requires evidence the item matched its description — the shipping receipt is largely irrelevant. Getting this wrong is the single biggest reason merchants lose disputes they should have won. Industry estimates suggest 60–70% of chargeback losses by merchants are winnable disputes responded to with the wrong evidence.

How reason codes differ between card networks

Each card network uses its own proprietary reason code system, and there is no universal standard. Visa uses two-part decimal codes (10.4, 13.1, 12.5) organised into four categories. Mastercard uses four-digit numeric codes (4853, 4837, 4808) grouped into similar categories. American Express uses alphanumeric codes (F30, C08, P23) that follow a letter-number format. Discover uses a mix of codes loosely aligned with the other networks.

The same underlying dispute — a customer claiming they never received their order — will generate a different reason code on Visa (13.1), Mastercard (4853), Amex (C08), and Discover (RM). Each of those four codes requires slightly different evidence, has a different response deadline, and is governed by different network rules. This is why processor-agnostic knowledge of reason codes matters more than memorising any one network's codes in isolation.

The four major dispute categories

Despite the differences between networks, chargeback reason codes across all four major networks fall into four broad categories:

• F
  Fraud disputes — The cardholder claims they did not authorise the transaction. This is the most common category and includes both true fraud (stolen card) and “friendly fraud” (cardholder disputes a transaction they did make). Visa 10.4, Mastercard 4837, Amex F24/F30 all fall here.
• A
  Authorisation disputes — The transaction was processed without proper authorisation, or the authorisation was declined but the transaction went through anyway. Visa 11.x and Mastercard 4808 are the main codes here.
• P
  Processing errors — Technical errors in how the transaction was processed — wrong amount, wrong currency, duplicate charge, late submission. These are often winnable if you have clean transaction records.
• C
  Consumer disputes — The cardholder received something different from what they expected: wrong item, damaged goods, service not rendered, subscription not cancelled. These require the most tailored responses and the widest range of evidence types.

Use the filter below to browse by network, or click any reason code to see the full evidence requirements, response strategy, and prevention steps.