Every chargeback your issuer files is tagged with a reason code — a number like Visa's 10.4 or Mastercard's 4837. Consumers almost never see these numbers, but they shape your case more than most people realize: the code decides which rulebook your dispute is judged under, what evidence the issuer expects, and sometimes even how long you have to file. This guide explains the main code families in plain language, so you can describe your situation in the terms your issuer will map to a code.
When you report a problem, your issuer opens a dispute and forwards a chargeback through the card network (Visa, Mastercard, Amex, or Discover). That chargeback has to carry a category — was this fraud, or goods never received, or something not as described? The reason code is that category. Each network publishes its own list of codes with definitions, timeframes, and evidence rules.
The practical point: you don't usually choose the code — your issuer assigns it based on your description of what happened. So describing the facts plainly and accurately at filing time matters, because the code your case gets determines the rules it plays by.
Visa groups its chargeback codes into families. The two that matter most to consumers:
The dividing line is simple in concept: did you authorize the charge? If no, you're in fraud territory (10.x). If yes, but the merchant failed to deliver, you're in the 13.x consumer-dispute family. Describing your situation around that question helps your issuer file under the right family. For the Visa-specific deadlines that flow from these codes, see our Visa dispute time limit page.
Mastercard uses its own numbering, but the logic is similar. The codes consumers encounter most:
As with Visa, the issuer picks the code from your description — and the same advice applies: be precise about whether the charge was unauthorized or whether it was an authorized payment that went wrong. Our Mastercard chargeback time limit page covers the deadlines for these filings.
Reason codes set the rules — but the calendar decides your case. Enter your dates and get your binding deadline.
American Express runs its own network and uses a smaller, differently named set of reason codes — but the underlying split is the same: unauthorized charges on one side, authorized-payment disputes (not received, not as described, cancelled, duplicate) on the other. Amex is also known for deciding disputes largely on its own terms rather than through the longer back-and-forth some other networks use. Our Amex dispute time limit page covers its filing window.
Here's why all of this numbering matters to you personally: not every code carries the same filing window. The standard ~120-day network window applies to most consumer-dispute codes, but some fraud-related codes carry shorter windows. That means two disputes filed the same week can have different deadlines, depending on how they were coded. Two takeaways:
One caution: reason codes get updated. Networks periodically renumber codes, revise definitions, and adjust which evidence each code requires. A blog post from two years ago may describe a code that no longer exists in that form. For the authoritative, current list, check the network's own dispute documentation — and confirm the practical details (deadlines, evidence expectations) with your issuer, since that's who applies the rules to your case.
A reason code is the category your issuer assigns your dispute when it files the chargeback with the card network — for example fraud, goods not received, or not as described. The code determines which network rules, deadlines, and evidence standards apply to your case.
Your issuer does, based on how you describe what happened when you file. That makes your initial description important: describe the facts plainly and accurately, because the issuer maps those facts to a code.
It can contribute to a denial. If the code doesn't match the facts — a service complaint filed under a fraud code, for example — the evidence standards for that code may not fit your case. If you suspect a mismatch, ask your issuer to review the category.
They can. Most consumer-dispute codes share the standard 120-day window, but some fraud-related codes carry shorter windows. That's one reason unauthorized charges deserve the fastest action — don't assume the full 120 days applies to every code.
The card networks publish their dispute guides with the current code lists, and they update them over time — codes get renumbered and definitions revised. Check the network's current documentation and confirm details with your issuer.
