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# Amex Token Service Flows

## American Express Token Service Flows

### Getting a Token

![Amex Token Service Flow](/_fern-img/c5272978bcd1dedf7688d85e23ce15916eca27a31bb5118aa7b3579cb700ac70.webp)

1. A Card Member initiates a transaction with a Merchant using a website, digital wallet, etc.
2. The Merchant exchanges the Card Member's account number and transaction data for a token and DCSC from AETS.
3. The Merchant stores a token from AETS in place of a Card Member's account number and keeps it for future use.

**NOTE:** Tokens may also be requested for Cards on File (CoF) outside of a transaction context.

### Authorizing a Purchase

![Amex Token Service Flow](/_fern-img/a513f6f68343be168f59ff8e2e74665adeb270e6d96bd45b934b29aec35cfb11.webp)

1. A Merchant submits a token and DCSC to the Acquirer for payment authorization.
2. The Acquirer requests authorization from the Issuer through the AMEX Network.
3. If the Issuer approves, the Acquirer sends the authorization confirmation to the Merchant.
4. The Merchant displays the payment confirmation to the Card Member.

### Updating Payment Data

![Amex Token Service Flow](/_fern-img/1e17d463609cb727fb82adcb6e0f09e3a07ac410541c325e87640cfd68182394.webp)

1. The Merchant and AETS notifies each other about the Card changes as it occurs, e.g., `The Card is removed by the Merchant`,` the Card is updated by the Issuer`, etc.