📣 Starting August 18, 2026, the new Chargeback Management Tool will be available.
1. What is a chargeback?
A chargeback is a mechanism in which the cardholder (the customer) formally disputes a credit or debit card payment with the card issuer, resulting in the reversal of the funds that were paid.
Chargebacks are typically initiated by the cardholder (the customer).
2. The chargeback flow (from occurrence to final decision)
The following is the standard process when a chargeback occurs.
| Step | Party | Details |
|---|---|---|
| 1. Dispute filed by the cardholder | Customer | The customer contacts the card issuer citing reasons such as "unauthorized use" or "I don't recognize this charge," and files a chargeback. |
| 2. Chargeback initiated | Card issuer | The issuer formally starts the chargeback procedure and notifies the payment processor (KOMOJU). |
| 3. Merchant response (defense) | KOMOJU / Merchant | KOMOJU notifies the merchant that a chargeback has occurred. The merchant can submit evidence (proof of delivery, signature, logs, etc.) showing that the transaction was legitimate. |
| 4. Review by the card issuer | Card issuer | The issuer weighs the evidence from both the customer and the merchant and makes a final decision. |
| 5. Final result | Card issuer |
Defense successful: If the transaction is deemed legitimate, the funds are retained by the merchant. Defense unsuccessful: If deemed fraudulent or improper, the funds are debited from the merchant and refunded to the customer. |
KOMOJU provides a Chargeback Management Tool that lets you manage all chargebacks in one place and respond quickly. See the related articles for detailed usage.